[syzbot] [bpf?] [net?] general protection fault in dev_map_enqueue

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fe46a7dd189e Merge tag 'sound-6.9-rc1' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=158ad421180000
kernel config: https://syzkaller.appspot.com/x/.config?x=fe78468a74fdc3b7
dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0f7abe4afac7/disk-fe46a7dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/82598d09246c/vmlinux-fe46a7dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/efa23788c875/bzImage-fe46a7dd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+af9492...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 13398 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539
Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 56 3a d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 60 89 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc90010e6f688 EFLAGS: 00010256
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc9000fb19000 RSI: 0000000000000c96 RDI: 0000000000000c97
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff8954502e
R10: 0000000000000004 R11: ffff88805bde3c00 R12: ffff88807e182000
R13: ffff88805595d070 R14: dffffc0000000000 R15: ffff8880b953c288
FS: 00007fe7632126c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32d23000 CR3: 000000006b1cc000 CR4: 0000000000350ef0
Call Trace:
<TASK>
__xdp_do_redirect_frame net/core/filter.c:4384 [inline]
xdp_do_redirect_frame+0x20d/0x4d0 net/core/filter.c:4438
xdp_test_run_batch net/bpf/test_run.c:336 [inline]
bpf_test_run_xdp_live+0xe8a/0x1e90 net/bpf/test_run.c:384
bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267
bpf_prog_test_run+0x33c/0x3b0 kernel/bpf/syscall.c:4240
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
do_syscall_64+0xfd/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fe76247dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe7632120c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fe7625abf80 RCX: 00007fe76247dda9
RDX: 0000000000000050 RSI: 0000000020000240 RDI: 000000000000000a
RBP: 00007fe7624ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe7625abf80 R15: 00007ffcf8e59e58
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539
Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 56 3a d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 60 89 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc90010e6f688 EFLAGS: 00010256
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc9000fb19000 RSI: 0000000000000c96 RDI: 0000000000000c97
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff8954502e
R10: 0000000000000004 R11: ffff88805bde3c00 R12: ffff88807e182000
R13: ffff88805595d070 R14: dffffc0000000000 R15: ffff8880b953c288
FS: 00007fe7632126c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32d23000 CR3: 000000006b1cc000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
0: 41 56 push %r14
2: 41 55 push %r13
4: 41 54 push %r12
6: 53 push %rbx
7: 48 83 ec 18 sub $0x18,%rsp
b: 49 89 d4 mov %rdx,%r12
e: 49 89 f5 mov %rsi,%r13
11: 48 89 fd mov %rdi,%rbp
14: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14
1b: fc ff df
1e: e8 56 3a d8 ff call 0xffd83a79
23: 48 89 e8 mov %rbp,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi
34: e8 60 89 3b 00 call 0x3b8999
39: 4c 8b 7d 00 mov 0x0(%rbp),%r15
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c5 .byte 0xc5


---
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If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 443574b03387 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: bpf
console+strace: https://syzkaller.appspot.com/x/log.txt?x=17d370b1180000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13d6b041180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1060cc81180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3f355021a085/disk-443574b0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/44cf4de7472a/vmlinux-443574b0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a99a36c7ad65/bzImage-443574b0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+af9492...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI

KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]

CPU: 1 PID: 5078 Comm: syz-executor295 Not tainted 6.8.0-syzkaller-05236-g443574b03387 #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539

Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 a6 42 d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 10 8a 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc90003bef688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888022169e00
RDX: 0000000000000000 RSI: ffff88802ef65070 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff894ff90e
R10: 0000000000000004 R11: ffff888022169e00 R12: ffff888015bd0000
R13: ffff88802ef65070 R14: dffffc0000000000 R15: ffff8880b953c088
FS: 000055558e3b9380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f1141b380d0 CR3: 0000000021838000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Call Trace:
<TASK>
__xdp_do_redirect_frame net/core/filter.c:4384 [inline]
xdp_do_redirect_frame+0x20d/0x4d0 net/core/filter.c:4438
xdp_test_run_batch net/bpf/test_run.c:336 [inline]
bpf_test_run_xdp_live+0xe8a/0x1e90 net/bpf/test_run.c:384
bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267

bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240

__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736

do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f1141ac0fb9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe180a1958 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1141ac0fb9
RDX: 0000000000000048 RSI: 0000000020000340 RDI: 000000000000000a
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000006

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539

Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 a6 42 d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 10 8a 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc90003bef688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888022169e00
RDX: 0000000000000000 RSI: ffff88802ef65070 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff894ff90e
R10: 0000000000000004 R11: ffff888022169e00 R12: ffff888015bd0000
R13: ffff88802ef65070 R14: dffffc0000000000 R15: ffff8880b953c088
FS: 000055558e3b9380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f1141b380d0 CR3: 0000000021838000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

----------------
Code disassembly (best guess):
0: 41 56 push %r14
2: 41 55 push %r13
4: 41 54 push %r12
6: 53 push %rbx
7: 48 83 ec 18 sub $0x18,%rsp
b: 49 89 d4 mov %rdx,%r12
e: 49 89 f5 mov %rsi,%r13
11: 48 89 fd mov %rdi,%rbp
14: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14
1b: fc ff df

1e: e8 a6 42 d8 ff call 0xffd842c9

23: 48 89 e8 mov %rbp,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi

34: e8 10 8a 3b 00 call 0x3b8a49

39: 4c 8b 7d 00 mov 0x0(%rbp),%r15
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c5 .byte 0xc5


---

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[Edward Adam Davis]

please test null ptr deref in dev_map_enqueue

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

diff --git a/net/core/filter.c b/net/core/filter.c
index 8adf95765cdd..721b85aebf58 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4381,6 +4381,11 @@ static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
err = dev_map_enqueue_multi(xdpf, dev, map,
ri->flags & BPF_F_EXCLUDE_INGRESS);
} else {
+ fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
+ if (unlikely(!fwd)) {
+ err = -EINVAL;
+ break;
+ }
err = dev_map_enqueue(fwd, xdpf, dev);
}
break;

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

7.829816][ T1] usbcore: registered new interface driver port100
[ 7.831413][ T1] usbcore: registered new interface driver nfcmrvl
[ 7.837905][ T1] Loading iSCSI transport class v2.0-870.
[ 7.858722][ T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[ 7.869143][ T1] ------------[ cut here ]------------
[ 7.870105][ T1] refcount_t: decrement hit 0; leaking memory.
[ 7.872514][ T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
[ 7.874530][ T1] Modules linked in:
[ 7.875370][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1-syzkaller-g7033999ecd7b-dirty #0
[ 7.877291][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
[ 7.879264][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 7.881153][ T1] Code: b2 00 00 00 e8 57 df e9 fc 5b 5d c3 cc cc cc cc e8 4b df e9 fc c6 05 4f 89 e8 0a 01 90 48 c7 c7 60 33 1f 8c e8 87 7b ac fc 90 <0f> 0b 90 90 eb d9 e8 2b df e9 fc c6 05 2c 89 e8 0a 01 90 48 c7 c7
[ 7.884566][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 7.885519][ T1] RAX: 2b377ad567545500 RBX: ffff888020dced4c RCX: ffff8880166d8000
[ 7.886879][ T1] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
[ 7.888277][ T1] RBP: 0000000000000004 R08: ffffffff815800c2 R09: fffffbfff1c396e0
[ 7.889846][ T1] R10: dffffc0000000000 R11: fffffbfff1c396e0 R12: ffffea000501edc0
[ 7.891597][ T1] R13: ffffea000501edc8 R14: 1ffffd4000a03db9 R15: 0000000000000000
[ 7.892863][ T1] FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
[ 7.896023][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7.897831][ T1] CR2: ffff88823ffff000 CR3: 000000000e132000 CR4: 00000000003506f0
[ 7.899872][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 7.902920][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 7.905308][ T1] Call Trace:
[ 7.906155][ T1] <TASK>
[ 7.907108][ T1] ? __warn+0x163/0x4e0
[ 7.908236][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.909628][ T1] ? report_bug+0x2b3/0x500
[ 7.911322][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.912413][ T1] ? handle_bug+0x3e/0x70
[ 7.913104][ T1] ? exc_invalid_op+0x1a/0x50
[ 7.913916][ T1] ? asm_exc_invalid_op+0x1a/0x20
[ 7.914971][ T1] ? __warn_printk+0x292/0x360
[ 7.915905][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.917491][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 7.919275][ T1] __free_pages_ok+0xc60/0xd90
[ 7.920758][ T1] make_alloc_exact+0xa3/0xf0
[ 7.921785][ T1] vring_alloc_queue_split+0x20a/0x600
[ 7.922946][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 7.929618][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 7.930612][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 7.931909][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 7.933205][ T1] ? really_probe+0x2b8/0xad0
[ 7.934463][ T1] ? driver_probe_device+0x50/0x430
[ 7.936429][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 7.937419][ T1] ? ret_from_fork+0x4b/0x80
[ 7.938584][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 7.940730][ T1] vring_create_virtqueue+0xca/0x110
[ 7.941726][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.942814][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.943976][ T1] setup_vq+0xe9/0x2d0
[ 7.944801][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.945576][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.946948][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.948006][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.949084][ T1] vp_setup_vq+0xbf/0x330
[ 7.949824][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 7.950979][ T1] ? ioread16+0x2f/0x90
[ 7.951822][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.953388][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 7.954915][ T1] vp_find_vqs+0x4c/0x4e0
[ 7.955862][ T1] virtscsi_init+0x8db/0xd00
[ 7.956749][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 7.957896][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 7.959614][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 7.961011][ T1] ? vp_get+0xfd/0x140
[ 7.962132][ T1] virtscsi_probe+0x3ea/0xf60
[ 7.962965][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 7.964000][ T1] ? vp_set+0x34d/0x350
[ 7.965137][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 7.966023][ T1] ? vp_set_status+0x1a/0x40
[ 7.966940][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 7.968109][ T1] ? virtio_features_ok+0x10c/0x270
[ 7.969198][ T1] virtio_dev_probe+0x991/0xaf0
[ 7.970151][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 7.971070][ T1] really_probe+0x2b8/0xad0
[ 7.971988][ T1] __driver_probe_device+0x1a2/0x390
[ 7.973433][ T1] driver_probe_device+0x50/0x430
[ 7.974431][ T1] __driver_attach+0x45f/0x710
[ 7.975759][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.977202][ T1] bus_for_each_dev+0x239/0x2b0
[ 7.978309][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.979888][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 7.981067][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 7.982284][ T1] bus_add_driver+0x347/0x620
[ 7.983346][ T1] driver_register+0x23a/0x320
[ 7.984227][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.985533][ T1] virtio_scsi_init+0x65/0xe0
[ 7.986807][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.988078][ T1] do_one_initcall+0x248/0x880
[ 7.989286][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.990438][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 7.991719][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 7.993284][ T1] ? __pfx_parse_args+0x10/0x10
[ 7.994653][ T1] ? do_initcalls+0x1c/0x80
[ 7.995768][ T1] ? rcu_is_watching+0x15/0xb0
[ 7.996707][ T1] do_initcall_level+0x157/0x210
[ 7.997710][ T1] do_initcalls+0x3f/0x80
[ 7.998399][ T1] kernel_init_freeable+0x435/0x5d0
[ 7.999965][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 8.001669][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.003259][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.003962][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.005204][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.006149][ T1] kernel_init+0x1d/0x2b0
[ 8.007084][ T1] ret_from_fork+0x4b/0x80
[ 8.008082][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.009623][ T1] ret_from_fork_asm+0x1a/0x30
[ 8.010782][ T1] </TASK>
[ 8.011305][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 8.012595][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1-syzkaller-g7033999ecd7b-dirty #0
[ 8.014252][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
[ 8.015689][ T1] Call Trace:
[ 8.016148][ T1] <TASK>
[ 8.016559][ T1] dump_stack_lvl+0x241/0x360
[ 8.017219][ T1] ? __pfx_dump_stack_lvl+0x10/0x10
[ 8.017934][ T1] ? __pfx__printk+0x10/0x10
[ 8.018600][ T1] ? _printk+0xd5/0x120
[ 8.019417][ T1] ? vscnprintf+0x5d/0x90
[ 8.020186][ T1] panic+0x349/0x860
[ 8.020754][ T1] ? __warn+0x172/0x4e0
[ 8.020754][ T1] ? __pfx_panic+0x10/0x10
[ 8.020754][ T1] ? show_trace_log_lvl+0x4e6/0x520
[ 8.020754][ T1] ? ret_from_fork_asm+0x1a/0x30
[ 8.020754][ T1] __warn+0x346/0x4e0
[ 8.020754][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.020754][ T1] report_bug+0x2b3/0x500
[ 8.020754][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.020754][ T1] handle_bug+0x3e/0x70
[ 8.020754][ T1] exc_invalid_op+0x1a/0x50
[ 8.020754][ T1] asm_exc_invalid_op+0x1a/0x20
[ 8.020754][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 8.020754][ T1] Code: b2 00 00 00 e8 57 df e9 fc 5b 5d c3 cc cc cc cc e8 4b df e9 fc c6 05 4f 89 e8 0a 01 90 48 c7 c7 60 33 1f 8c e8 87 7b ac fc 90 <0f> 0b 90 90 eb d9 e8 2b df e9 fc c6 05 2c 89 e8 0a 01 90 48 c7 c7
[ 8.030364][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 8.030364][ T1] RAX: 2b377ad567545500 RBX: ffff888020dced4c RCX: ffff8880166d8000
[ 8.030364][ T1] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
[ 8.030364][ T1] RBP: 0000000000000004 R08: ffffffff815800c2 R09: fffffbfff1c396e0
[ 8.030364][ T1] R10: dffffc0000000000 R11: fffffbfff1c396e0 R12: ffffea000501edc0
[ 8.030364][ T1] R13: ffffea000501edc8 R14: 1ffffd4000a03db9 R15: 0000000000000000
[ 8.030364][ T1] ? __warn_printk+0x292/0x360
[ 8.030364][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 8.040252][ T1] __free_pages_ok+0xc60/0xd90
[ 8.040252][ T1] make_alloc_exact+0xa3/0xf0
[ 8.040252][ T1] vring_alloc_queue_split+0x20a/0x600
[ 8.040252][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 8.040252][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 8.040252][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 8.040252][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 8.040252][ T1] ? really_probe+0x2b8/0xad0
[ 8.040252][ T1] ? driver_probe_device+0x50/0x430
[ 8.040252][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 8.040252][ T1] ? ret_from_fork+0x4b/0x80
[ 8.050346][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 8.050346][ T1] vring_create_virtqueue+0xca/0x110
[ 8.050346][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.050346][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.050346][ T1] setup_vq+0xe9/0x2d0
[ 8.050346][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.050346][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.050346][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.050346][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.050346][ T1] vp_setup_vq+0xbf/0x330
[ 8.050346][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 8.050346][ T1] ? ioread16+0x2f/0x90
[ 8.050346][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.050346][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 8.060243][ T1] vp_find_vqs+0x4c/0x4e0
[ 8.060243][ T1] virtscsi_init+0x8db/0xd00
[ 8.060243][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 8.060243][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 8.060243][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 8.060243][ T1] ? vp_get+0xfd/0x140
[ 8.060243][ T1] virtscsi_probe+0x3ea/0xf60
[ 8.060243][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 8.060243][ T1] ? vp_set+0x34d/0x350
[ 8.060243][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 8.060243][ T1] ? vp_set_status+0x1a/0x40
[ 8.060243][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 8.060243][ T1] ? virtio_features_ok+0x10c/0x270
[ 8.070334][ T1] virtio_dev_probe+0x991/0xaf0
[ 8.070334][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 8.070334][ T1] really_probe+0x2b8/0xad0
[ 8.070334][ T1] __driver_probe_device+0x1a2/0x390
[ 8.070334][ T1] driver_probe_device+0x50/0x430
[ 8.070334][ T1] __driver_attach+0x45f/0x710
[ 8.070334][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.070334][ T1] bus_for_each_dev+0x239/0x2b0
[ 8.070334][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.070334][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 8.070334][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 8.070334][ T1] bus_add_driver+0x347/0x620
[ 8.080263][ T1] driver_register+0x23a/0x320
[ 8.080263][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.080263][ T1] virtio_scsi_init+0x65/0xe0
[ 8.080263][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.080263][ T1] do_one_initcall+0x248/0x880
[ 8.080263][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.080263][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.080263][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 8.080263][ T1] ? __pfx_parse_args+0x10/0x10
[ 8.080263][ T1] ? do_initcalls+0x1c/0x80
[ 8.080263][ T1] ? rcu_is_watching+0x15/0xb0
[ 8.080263][ T1] do_initcall_level+0x157/0x210
[ 8.080263][ T1] do_initcalls+0x3f/0x80
[ 8.080263][ T1] kernel_init_freeable+0x435/0x5d0
[ 8.090336][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 8.090336][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.090336][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.090336][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.090336][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.090336][ T1] kernel_init+0x1d/0x2b0
[ 8.090336][ T1] ret_from_fork+0x4b/0x80
[ 8.090336][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.090336][ T1] ret_from_fork_asm+0x1a/0x30
[ 8.090336][ T1] </TASK>
[ 8.090336][ T1] Kernel Offset: disabled
[ 8.090336][ T1] Rebooting in 86400 seconds..


syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/syzkaller/jobs-2/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs-2/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.4'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3591245852=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 454571b6a
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"454571b6a16598f5a6e015b9fb1a04932bce7ab9\"


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=12d2cb65180000


Tested on:

commit: 7033999e Merge tag 'printk-for-6.9-rc2' of git://git.k..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
kernel config: https://syzkaller.appspot.com/x/.config?x=7b667bc37450fdcd

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=1066d421180000

[Alexei Starovoitov]

Toke, Jesper,

please take a look.
It's reproducible 100% of the time.
dst is NULL in dev_map_enqueue().

Thanks

[Edward Adam Davis]

please test null ptr deref in dev_map_enqueue

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 66a27abac311

diff --git a/net/core/filter.c b/net/core/filter.c
index 8adf95765cdd..721b85aebf58 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c

@@ -4381,6 +4381,10 @@ static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,

err = dev_map_enqueue_multi(xdpf, dev, map,
ri->flags & BPF_F_EXCLUDE_INGRESS);
} else {

[Jesper Dangaard Brouer]

On 27/03/2024 16.19, Alexei Starovoitov wrote:
> Toke, Jesper,
>
> please take a look.
> It's reproducible 100% of the time.
> dst is NULL in dev_map_enqueue().
>

The `dst` (NULL) is basically `ri->tgt_value` being passed through
(unmodified) via xdp_do_redirect_frame() and __xdp_do_redirect_frame()
into dev_map_enqueue().

I think something is wrong in xdp_test_run_batch().
The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().

Toke, can you take a look at xdp_test_run_batch() and where
`ri->tgt_value` is getting set?

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

erface driver port100
[ 7.948791][ T1] usbcore: registered new interface driver nfcmrvl
[ 7.955639][ T1] Loading iSCSI transport class v2.0-870.
[ 7.973810][ T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[ 7.989145][ T1] ------------[ cut here ]------------
[ 7.990111][ T1] refcount_t: decrement hit 0; leaking memory.
[ 7.991339][ T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
[ 7.993340][ T1] Modules linked in:
[ 7.994199][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.8.0-syzkaller-11136-g66a27abac311-dirty #0
[ 7.997619][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[ 8.000127][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 8.001771][ T1] Code: b2 00 00 00 e8 e7 e2 ec fc 5b 5d c3 cc cc cc cc e8 db e2 ec fc c6 05 c6 89 ea 0a 01 90 48 c7 c7 60 ae 1e 8c e8 47 a8 af fc 90 <0f> 0b 90 90 eb d9 e8 bb e2 ec fc c6 05 a3 89 ea 0a 01 90 48 c7 c7
[ 8.004380][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 8.005254][ T1] RAX: ca7328f93391fe00 RBX: ffff888020f9e75c RCX: ffff8880166e0000
[ 8.006549][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 8.008086][ T1] RBP: 0000000000000004 R08: ffffffff8157e022 R09: fffffbfff1c39660
[ 8.009562][ T1] R10: dffffc0000000000 R11: fffffbfff1c39660 R12: ffffea0000851dc0
[ 8.011291][ T1] R13: ffffea0000851dc8 R14: 1ffffd400010a3b9 R15: 0000000000000000
[ 8.012581][ T1] FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
[ 8.014131][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 8.016303][ T1] CR2: ffff88823ffff000 CR3: 000000000e132000 CR4: 00000000003506f0
[ 8.017899][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 8.019084][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 8.020661][ T1] Call Trace:
[ 8.021839][ T1] <TASK>
[ 8.022284][ T1] ? __warn+0x163/0x4b0
[ 8.022899][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.024608][ T1] ? report_bug+0x2b3/0x500
[ 8.025925][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.030150][ T1] ? handle_bug+0x3e/0x70
[ 8.031086][ T1] ? exc_invalid_op+0x1a/0x50
[ 8.033097][ T1] ? asm_exc_invalid_op+0x1a/0x20
[ 8.034748][ T1] ? __warn_printk+0x292/0x360
[ 8.037244][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.039638][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 8.041044][ T1] __free_pages_ok+0xc42/0xd70
[ 8.042367][ T1] make_alloc_exact+0xa3/0xf0
[ 8.044313][ T1] vring_alloc_queue_split+0x20a/0x600
[ 8.046844][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 8.048504][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 8.049295][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 8.050056][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 8.051457][ T1] ? really_probe+0x29e/0xc50
[ 8.053456][ T1] ? driver_probe_device+0x50/0x430
[ 8.054843][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 8.056263][ T1] ? ret_from_fork+0x4b/0x80
[ 8.057026][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 8.058003][ T1] vring_create_virtqueue+0xca/0x110
[ 8.058950][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.060241][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.061548][ T1] setup_vq+0xe9/0x2d0
[ 8.062720][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.066249][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.068677][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.070491][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.071820][ T1] vp_setup_vq+0xbf/0x330
[ 8.073020][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 8.075411][ T1] ? ioread16+0x2f/0x90
[ 8.076389][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.077767][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 8.078910][ T1] vp_find_vqs+0x4c/0x4e0
[ 8.080111][ T1] virtscsi_init+0x8db/0xd00
[ 8.081712][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 8.082801][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 8.083916][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 8.085236][ T1] ? vp_get+0xfd/0x140
[ 8.086319][ T1] virtscsi_probe+0x3ea/0xf60
[ 8.087214][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 8.090404][ T1] ? __pfx_vp_legacy_set_queue_address+0xd/0x10
[ 8.093111][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 8.094419][ T1] ? vp_set_status+0x1a/0x40
[ 8.096021][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 8.099934][ T1] ? virtio_features_ok+0x10c/0x270
[ 8.101665][ T1] virtio_dev_probe+0x991/0xaf0
[ 8.102487][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 8.105262][ T1] really_probe+0x29e/0xc50
[ 8.106620][ T1] __driver_probe_device+0x1a2/0x3e0
[ 8.108641][ T1] driver_probe_device+0x50/0x430
[ 8.110744][ T1] __driver_attach+0x45f/0x710
[ 8.112598][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.114221][ T1] bus_for_each_dev+0x239/0x2b0
[ 8.115430][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.116906][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 8.120034][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 8.121570][ T1] bus_add_driver+0x347/0x620
[ 8.123679][ T1] driver_register+0x23a/0x320
[ 8.125189][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.127373][ T1] virtio_scsi_init+0x65/0xe0
[ 8.128421][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.129199][ T1] do_one_initcall+0x238/0x830
[ 8.129859][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.130668][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.132091][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 8.133177][ T1] ? __pfx_parse_args+0x10/0x10
[ 8.134004][ T1] ? do_initcalls+0x1c/0x80
[ 8.134724][ T1] ? rcu_is_watching+0x15/0xb0
[ 8.135571][ T1] do_initcall_level+0x157/0x210
[ 8.136670][ T1] do_initcalls+0x3f/0x80
[ 8.137348][ T1] kernel_init_freeable+0x435/0x5d0
[ 8.138236][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 8.139208][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.142052][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.143016][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.144221][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.145741][ T1] kernel_init+0x1d/0x2b0
[ 8.146662][ T1] ret_from_fork+0x4b/0x80
[ 8.147514][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.148713][ T1] ret_from_fork_asm+0x1a/0x30
[ 8.149784][ T1] </TASK>
[ 8.150600][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 8.152093][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.8.0-syzkaller-11136-g66a27abac311-dirty #0
[ 8.154786][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[ 8.155798][ T1] Call Trace:
[ 8.155798][ T1] <TASK>
[ 8.155798][ T1] dump_stack_lvl+0x241/0x360
[ 8.155798][ T1] ? __pfx_dump_stack_lvl+0x10/0x10
[ 8.155798][ T1] ? __pfx__printk+0x10/0x10
[ 8.155798][ T1] ? _printk+0xd5/0x120
[ 8.155798][ T1] ? vscnprintf+0x5d/0x90
[ 8.155798][ T1] panic+0x349/0x860
[ 8.155798][ T1] ? __warn+0x172/0x4b0
[ 8.155798][ T1] ? __pfx_panic+0x10/0x10
[ 8.155798][ T1] ? show_trace_log_lvl+0x4e6/0x520
[ 8.155798][ T1] ? ret_from_fork_asm+0x1a/0x30
[ 8.155798][ T1] __warn+0x31e/0x4b0
[ 8.155798][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.155798][ T1] report_bug+0x2b3/0x500
[ 8.155798][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 8.155798][ T1] handle_bug+0x3e/0x70
[ 8.155798][ T1] exc_invalid_op+0x1a/0x50
[ 8.155798][ T1] asm_exc_invalid_op+0x1a/0x20
[ 8.155798][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 8.155798][ T1] Code: b2 00 00 00 e8 e7 e2 ec fc 5b 5d c3 cc cc cc cc e8 db e2 ec fc c6 05 c6 89 ea 0a 01 90 48 c7 c7 60 ae 1e 8c e8 47 a8 af fc 90 <0f> 0b 90 90 eb d9 e8 bb e2 ec fc c6 05 a3 89 ea 0a 01 90 48 c7 c7
[ 8.155798][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 8.155798][ T1] RAX: ca7328f93391fe00 RBX: ffff888020f9e75c RCX: ffff8880166e0000
[ 8.155798][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 8.155798][ T1] RBP: 0000000000000004 R08: ffffffff8157e022 R09: fffffbfff1c39660
[ 8.155798][ T1] R10: dffffc0000000000 R11: fffffbfff1c39660 R12: ffffea0000851dc0
[ 8.196035][ T1] R13: ffffea0000851dc8 R14: 1ffffd400010a3b9 R15: 0000000000000000
[ 8.196035][ T1] ? __warn_printk+0x292/0x360
[ 8.196035][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 8.196035][ T1] __free_pages_ok+0xc42/0xd70
[ 8.196035][ T1] make_alloc_exact+0xa3/0xf0
[ 8.196035][ T1] vring_alloc_queue_split+0x20a/0x600
[ 8.196035][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 8.196035][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 8.196035][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 8.196035][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 8.196035][ T1] ? really_probe+0x29e/0xc50
[ 8.196035][ T1] ? driver_probe_device+0x50/0x430
[ 8.196035][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 8.196035][ T1] ? ret_from_fork+0x4b/0x80
[ 8.196035][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 8.196035][ T1] vring_create_virtqueue+0xca/0x110
[ 8.196035][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.196035][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.196035][ T1] setup_vq+0xe9/0x2d0
[ 8.196035][ T1] ? __pfx_vp_notify+0x10/0x10
[ 8.196035][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.196035][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.196035][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.196035][ T1] vp_setup_vq+0xbf/0x330
[ 8.196035][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 8.196035][ T1] ? ioread16+0x2f/0x90
[ 8.196035][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 8.196035][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 8.196035][ T1] vp_find_vqs+0x4c/0x4e0
[ 8.196035][ T1] virtscsi_init+0x8db/0xd00
[ 8.196035][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 8.196035][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 8.196035][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 8.196035][ T1] ? vp_get+0xfd/0x140
[ 8.196035][ T1] virtscsi_probe+0x3ea/0xf60
[ 8.196035][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 8.196035][ T1] ? __pfx_vp_legacy_set_queue_address+0xd/0x10
[ 8.196035][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 8.196035][ T1] ? vp_set_status+0x1a/0x40
[ 8.196035][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 8.196035][ T1] ? virtio_features_ok+0x10c/0x270
[ 8.196035][ T1] virtio_dev_probe+0x991/0xaf0
[ 8.196035][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 8.196035][ T1] really_probe+0x29e/0xc50
[ 8.196035][ T1] __driver_probe_device+0x1a2/0x3e0
[ 8.196035][ T1] driver_probe_device+0x50/0x430
[ 8.196035][ T1] __driver_attach+0x45f/0x710
[ 8.196035][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.196035][ T1] bus_for_each_dev+0x239/0x2b0
[ 8.196035][ T1] ? __pfx___driver_attach+0x10/0x10
[ 8.196035][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 8.196035][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 8.246039][ T1] bus_add_driver+0x347/0x620
[ 8.246039][ T1] driver_register+0x23a/0x320
[ 8.246039][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.246039][ T1] virtio_scsi_init+0x65/0xe0
[ 8.246039][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.246039][ T1] do_one_initcall+0x238/0x830
[ 8.246039][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 8.246039][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.246039][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 8.246039][ T1] ? __pfx_parse_args+0x10/0x10
[ 8.246039][ T1] ? do_initcalls+0x1c/0x80
[ 8.246039][ T1] ? rcu_is_watching+0x15/0xb0
[ 8.246039][ T1] do_initcall_level+0x157/0x210
[ 8.246039][ T1] do_initcalls+0x3f/0x80
[ 8.246039][ T1] kernel_init_freeable+0x435/0x5d0
[ 8.246039][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 8.246039][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 8.246039][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.246039][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.246039][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.246039][ T1] kernel_init+0x1d/0x2b0
[ 8.246039][ T1] ret_from_fork+0x4b/0x80
[ 8.246039][ T1] ? __pfx_kernel_init+0x10/0x10
[ 8.246039][ T1] ret_from_fork_asm+0x1a/0x30
[ 8.246039][ T1] </TASK>
[ 8.246039][ T1] Kernel Offset: disabled
[ 8.246039][ T1] Rebooting in 86400 seconds..

syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''

GOMODCACHE='/syzkaller/jobs/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs/linux/gopath'

GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.4'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'

GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'

GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'

GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build1926694584=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 454571b6a
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"454571b6a16598f5a6e015b9fb1a04932bce7ab9\"


Error text is too large and was truncated, full error text is at:

https://syzkaller.appspot.com/x/error.txt?x=114224ee180000


Tested on:

commit: 66a27aba Merge tag 'powerpc-6.9-1' of git://git.kernel..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config: https://syzkaller.appspot.com/x/.config?x=9f5be5e6842dd192

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=1624aed9180000

[Toke Høiland-Jørgensen]

Jesper Dangaard Brouer <ha...@kernel.org> writes:

> On 27/03/2024 16.19, Alexei Starovoitov wrote:
>> Toke, Jesper,
>>
>> please take a look.
>> It's reproducible 100% of the time.
>> dst is NULL in dev_map_enqueue().
>>
>
> The `dst` (NULL) is basically `ri->tgt_value` being passed through
> (unmodified) via xdp_do_redirect_frame() and __xdp_do_redirect_frame()
> into dev_map_enqueue().
>
> I think something is wrong in xdp_test_run_batch().
> The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
> cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().
>
> Toke, can you take a look at xdp_test_run_batch() and where
> `ri->tgt_value` is getting set?

Sure! I'm off for Easter, but I'll take a look when I get back next week :)

-Toke

[Edward Adam Davis]

please test null ptr deref in dev_map_enqueue

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git 443574b03387

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+af9492...@syzkaller.appspotmail.com

Tested on:

commit: 443574b0 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git
console output: https://syzkaller.appspot.com/x/log.txt?x=12df8ffd180000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=16742f45180000

Note: testing is done by a robot and is best-effort only.

[Edward Adam Davis]

please test null ptr deref in dev_map_enqueue

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git 443574b03387

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 4e2cdbb5629f..ef20de14154a 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -86,6 +86,7 @@ struct bpf_dtab {
static DEFINE_PER_CPU(struct list_head, dev_flush_list);
static DEFINE_SPINLOCK(dev_map_lock);
static LIST_HEAD(dev_map_list);
+static bool is_valid_dst(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf);

static struct hlist_head *dev_map_create_hash(unsigned int entries,
int numa_node)
@@ -536,7 +537,10 @@ int dev_xdp_enqueue(struct net_device *dev, struct xdp_frame *xdpf,
int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_frame *xdpf,
struct net_device *dev_rx)
{
- struct net_device *dev = dst->dev;
+ struct net_device *dev;
+ if (!is_valid_dst(dst, xdpf))
+ return -EINVAL;
+ dev = dst->dev;

return __xdp_enqueue(dev, xdpf, dev_rx, dst->xdp_prog);
}

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+af9492...@syzkaller.appspotmail.com

Tested on:

commit: 443574b0 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

console output: https://syzkaller.appspot.com/x/log.txt?x=11097d0d180000

kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=152ec3b1180000

[Edward Adam Davis]

[Syzbot reported]

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]

CPU: 0 PID: 5179 Comm: syz-executor120 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539

Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 e6 45 d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 d0 8b 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc90003b0f688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888025258000
RDX: 0000000000000000 RSI: ffff888024035070 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff894ff55e
R10: 0000000000000004 R11: ffff888025258000 R12: ffff8880157d8000
R13: ffff888024035070 R14: dffffc0000000000 R15: ffff8880b943c088
FS: 00007fd0098e46c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00000000200009c0 CR3: 0000000025314000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__xdp_do_redirect_frame net/core/filter.c:4384 [inline]
xdp_do_redirect_frame+0x20d/0x4d0 net/core/filter.c:4438
xdp_test_run_batch net/bpf/test_run.c:336 [inline]
bpf_test_run_xdp_live+0xe8a/0x1e90 net/bpf/test_run.c:384
bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267
bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75

RIP: 0033:0x7fd00992a0d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd0098e4238 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fd0099b43e8 RCX: 00007fd00992a0d9

RDX: 0000000000000050 RSI: 0000000020000240 RDI: 000000000000000a

RBP: 00007fd0099b43e0 R08: 00007fd0098e46c0 R09: 00007fd0098e46c0
R10: 00007fd0098e46c0 R11: 0000000000000246 R12: 00007fd009981060
R13: 0000000000000016 R14: 00007fffcb70c160 R15: 00007fffcb70c248
</TASK>
[Fix]
On the execution path of bpf_prog_test_run(), due to ri->map being NULL,
ri->tgtvalue was not set correctly.

Reported-and-tested-by: syzbot+af9492...@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <ead...@qq.com>
---
kernel/bpf/devmap.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 4e2cdbb5629f..ef20de14154a 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -86,6 +86,7 @@ struct bpf_dtab {
static DEFINE_PER_CPU(struct list_head, dev_flush_list);
static DEFINE_SPINLOCK(dev_map_lock);
static LIST_HEAD(dev_map_list);
+static bool is_valid_dst(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf);

static struct hlist_head *dev_map_create_hash(unsigned int entries,
int numa_node)
@@ -536,7 +537,10 @@ int dev_xdp_enqueue(struct net_device *dev, struct xdp_frame *xdpf,
int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_frame *xdpf,
struct net_device *dev_rx)
{
- struct net_device *dev = dst->dev;
+ struct net_device *dev;
+ if (!is_valid_dst(dst, xdpf))
+ return -EINVAL;
+ dev = dst->dev;

return __xdp_enqueue(dev, xdpf, dev_rx, dst->xdp_prog);
}

--
2.43.0

[Jesper Dangaard Brouer]

This is overkill, because __xdp_enqueue() already contains most of the
checks in is_valid_dst().

Why not:

if (!dst)
return -EINVAL;

> + return -EINVAL;
> + dev = dst->dev;
>
> return __xdp_enqueue(dev, xdpf, dev_rx, dst->xdp_prog);
> }

Is this fix pampering over another issue?

To repeat myself:

I think something is wrong in xdp_test_run_batch().
The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().

Is this a case of XDP program returning XDP_REDIRECT without having
called the BPF helper for redirect?

--Jesper

[Edward Adam Davis]

This can work, but I think is_valid_dst() is better, as its internal inspection
of dst is more thorough.

>
>
> > + return -EINVAL;
> > + dev = dst->dev;
> >
> > return __xdp_enqueue(dev, xdpf, dev_rx, dst->xdp_prog);
> > }
>
>
> Is this fix pampering over another issue?
>
> To repeat myself:
> I think something is wrong in xdp_test_run_batch().
> The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
> cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().

As I mentioned earlier, because the value of "ri->map" is NULL, even if it can
be executed to __bpf_xdp_redirect_map(), it is meaningless because "ri->map" is
used internally to set "ri->tgt_value".

>
> Is this a case of XDP program returning XDP_REDIRECT without having
> called the BPF helper for redirect?

Edward

[Jesper Dangaard Brouer]

No, is_valid_dst() is not better, because it will repeat almost same
checks (as I said) as __xdp_enqueue() already contains these checks.
This is fast-path code, we don't want to repeat checks.

--Jesper
(copy-pasted function below to easier compare)

static inline int __xdp_enqueue(struct net_device *dev, struct xdp_frame
*xdpf,
struct net_device *dev_rx,
struct bpf_prog *xdp_prog)
{
int err;

if (!(dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT))
return -EOPNOTSUPP;

if (unlikely(!(dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT_SG) &&
xdp_frame_has_frags(xdpf)))
return -EOPNOTSUPP;

err = xdp_ok_fwd_dev(dev, xdp_get_frame_len(xdpf));
if (unlikely(err))
return err;

bq_enqueue(dev, xdpf, dev_rx, xdp_prog);
return 0;

}


static bool is_valid_dst(struct bpf_dtab_netdev *obj, struct xdp_frame
*xdpf)

{
if (!obj)
return false;

if (!(obj->dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT))
return false;

if (unlikely(!(obj->dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT_SG) &&
xdp_frame_has_frags(xdpf)))
return false;

if (xdp_ok_fwd_dev(obj->dev, xdp_get_frame_len(xdpf)))
return false;

return true;
}

[Toke Høiland-Jørgensen]

Jesper Dangaard Brouer <ha...@kernel.org> writes:

I did spot a bug in the test_run code related to XDP_TX, but I don't
really see how that particular issue could trigger this bug, since
AFAICT the reproducer doesn't return XDP_TX. It looks like the program
is setting the BROADCAST flag, but I don't see how that can lead to
dev_map_enqueue() being run.

> The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
> cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().

__bpf_xdp_redirect_map() is always being called from inside the BPF
programs (through the bpf_redirect_map()). I don't really think we have
a way of ensuring that we always follow such a call with an XDP_REDIRECT
return, so we're kinda relying on the XDP program to do the right thing,
or we could risk stale data being left in bpf_redirect_info, no? I am
not sure if that is what's going on here, though.

> Is this a case of XDP program returning XDP_REDIRECT without having
> called the BPF helper for redirect?

From trying to run the reproducer, I don't *think* that is the case, but
cf the above I don't think that is the case in this instance.

Anyway, let's see if I can get syzbot to test the fix to
xdp_test_run_batch():

#syz test

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index dfd919374017..a3f24486829e 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -281,9 +281,9 @@ static int xdp_recv_frames(struct xdp_frame **frames, int nframes,
static int xdp_test_run_batch(struct xdp_test_data *xdp, struct bpf_prog *prog,
u32 repeat)
{
- struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
int err = 0, act, ret, i, nframes = 0, batch_sz;
struct xdp_frame **frames = xdp->frames;
+ struct bpf_redirect_info *ri;
struct xdp_page_head *head;
struct xdp_frame *frm;
bool redirect = false;
@@ -294,6 +294,7 @@ static int xdp_test_run_batch(struct xdp_test_data *xdp, struct bpf_prog *prog,

local_bh_disable();
xdp_set_return_frame_no_direct();
+ ri = this_cpu_ptr(&bpf_redirect_info);

for (i = 0; i < batch_sz; i++) {
page = page_pool_dev_alloc_pages(xdp->pp);

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

erface driver port100

[ 7.311436][ T1] usbcore: registered new interface driver nfcmrvl
[ 7.318515][ T1] Loading iSCSI transport class v2.0-870.
[ 7.335287][ T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[ 7.343626][ T1] ------------[ cut here ]------------
[ 7.344498][ T1] refcount_t: decrement hit 0; leaking memory.
[ 7.345816][ T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
[ 7.347895][ T1] Modules linked in:
[ 7.348644][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1-syzkaller-00245-g1cfa2f10f4e9-dirty #0
[ 7.350284][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[ 7.351743][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 7.352725][ T1] Code: b2 00 00 00 e8 97 cf e9 fc 5b 5d c3 cc cc cc cc e8 8b cf e9 fc c6 05 6e 74 e8 0a 01 90 48 c7 c7 e0 33 1f 8c e8 c7 6b ac fc 90 <0f> 0b 90 90 eb d9 e8 6b cf e9 fc c6 05 4b 74 e8 0a 01 90 48 c7 c7
[ 7.355628][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 7.356908][ T1] RAX: 97987c7bd8eab100 RBX: ffff8881472d6f6c RCX: ffff8880166d0000
[ 7.358339][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 7.359509][ T1] RBP: 0000000000000004 R08: ffffffff81580062 R09: fffffbfff1c396e0
[ 7.360660][ T1] R10: dffffc0000000000 R11: fffffbfff1c396e0 R12: ffffea0000856dc0
[ 7.361924][ T1] R13: ffffea0000856dc8 R14: 1ffffd400010adb9 R15: 0000000000000000
[ 7.363052][ T1] FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
[ 7.364304][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7.365198][ T1] CR2: ffff88823ffff000 CR3: 000000000e132000 CR4: 00000000003506f0
[ 7.367259][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 7.368495][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 7.369779][ T1] Call Trace:
[ 7.370257][ T1] <TASK>
[ 7.370879][ T1] ? __warn+0x163/0x4e0
[ 7.371456][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.372221][ T1] ? report_bug+0x2b3/0x500
[ 7.372874][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.373951][ T1] ? handle_bug+0x3e/0x70
[ 7.374586][ T1] ? exc_invalid_op+0x1a/0x50
[ 7.375235][ T1] ? asm_exc_invalid_op+0x1a/0x20
[ 7.375940][ T1] ? __warn_printk+0x292/0x360
[ 7.376982][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.377792][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 7.378630][ T1] __free_pages_ok+0xc60/0xd90
[ 7.379362][ T1] make_alloc_exact+0xa3/0xf0
[ 7.380045][ T1] vring_alloc_queue_split+0x20a/0x600
[ 7.380857][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 7.381697][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 7.382711][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 7.383786][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 7.384631][ T1] ? really_probe+0x2b8/0xad0
[ 7.385324][ T1] ? driver_probe_device+0x50/0x430
[ 7.386103][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 7.387313][ T1] ? ret_from_fork+0x4b/0x80
[ 7.388031][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 7.389084][ T1] vring_create_virtqueue+0xca/0x110
[ 7.389967][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.390812][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.391660][ T1] setup_vq+0xe9/0x2d0
[ 7.392432][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.393181][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.393942][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.394867][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.395927][ T1] vp_setup_vq+0xbf/0x330
[ 7.397180][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 7.398233][ T1] ? ioread16+0x2f/0x90
[ 7.398859][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.399621][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 7.400563][ T1] vp_find_vqs+0x4c/0x4e0
[ 7.401171][ T1] virtscsi_init+0x8db/0xd00
[ 7.401888][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 7.402696][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 7.403594][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 7.404281][ T1] ? vp_get+0xfd/0x140
[ 7.404929][ T1] virtscsi_probe+0x3ea/0xf60
[ 7.405637][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 7.406398][ T1] ? virtio_pci_modern_probe+0x1ad/0x270
[ 7.407182][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 7.407898][ T1] ? vp_set_status+0x1a/0x40
[ 7.408529][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 7.409355][ T1] ? virtio_features_ok+0x10c/0x270
[ 7.410072][ T1] virtio_dev_probe+0x991/0xaf0
[ 7.410754][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 7.411546][ T1] really_probe+0x2b8/0xad0
[ 7.412167][ T1] __driver_probe_device+0x1a2/0x390
[ 7.412887][ T1] driver_probe_device+0x50/0x430
[ 7.413590][ T1] __driver_attach+0x45f/0x710
[ 7.414237][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.414953][ T1] bus_for_each_dev+0x239/0x2b0
[ 7.415674][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.416541][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 7.417323][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 7.418091][ T1] bus_add_driver+0x347/0x620
[ 7.418770][ T1] driver_register+0x23a/0x320
[ 7.419601][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.420387][ T1] virtio_scsi_init+0x65/0xe0
[ 7.421063][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.421802][ T1] do_one_initcall+0x248/0x880
[ 7.422452][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.423191][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 7.424043][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 7.424842][ T1] ? __pfx_parse_args+0x10/0x10
[ 7.425562][ T1] ? do_initcalls+0x1c/0x80
[ 7.426235][ T1] ? rcu_is_watching+0x15/0xb0
[ 7.426902][ T1] do_initcall_level+0x157/0x210
[ 7.427580][ T1] do_initcalls+0x3f/0x80
[ 7.428174][ T1] kernel_init_freeable+0x435/0x5d0
[ 7.428912][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 7.429687][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 7.430608][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.431281][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.432008][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.432791][ T1] kernel_init+0x1d/0x2b0
[ 7.433667][ T1] ret_from_fork+0x4b/0x80
[ 7.434410][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.435247][ T1] ret_from_fork_asm+0x1a/0x30
[ 7.436036][ T1] </TASK>
[ 7.436777][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 7.437767][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1-syzkaller-00245-g1cfa2f10f4e9-dirty #0
[ 7.439106][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[ 7.440461][ T1] Call Trace:
[ 7.440914][ T1] <TASK>
[ 7.441323][ T1] dump_stack_lvl+0x241/0x360
[ 7.441989][ T1] ? __pfx_dump_stack_lvl+0x10/0x10
[ 7.442706][ T1] ? __pfx__printk+0x10/0x10
[ 7.443350][ T1] ? _printk+0xd5/0x120
[ 7.443977][ T1] ? vscnprintf+0x5d/0x90
[ 7.444934][ T1] panic+0x349/0x860
[ 7.445694][ T1] ? __warn+0x172/0x4e0
[ 7.446290][ T1] ? __pfx_panic+0x10/0x10
[ 7.446639][ T1] ? show_trace_log_lvl+0x4e6/0x520
[ 7.446639][ T1] ? ret_from_fork_asm+0x1a/0x30
[ 7.446639][ T1] __warn+0x346/0x4e0
[ 7.446639][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.446639][ T1] report_bug+0x2b3/0x500
[ 7.446639][ T1] ? refcount_warn_saturate+0xfa/0x1d0
[ 7.446639][ T1] handle_bug+0x3e/0x70
[ 7.446639][ T1] exc_invalid_op+0x1a/0x50
[ 7.446639][ T1] asm_exc_invalid_op+0x1a/0x20
[ 7.446639][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[ 7.446639][ T1] Code: b2 00 00 00 e8 97 cf e9 fc 5b 5d c3 cc cc cc cc e8 8b cf e9 fc c6 05 6e 74 e8 0a 01 90 48 c7 c7 e0 33 1f 8c e8 c7 6b ac fc 90 <0f> 0b 90 90 eb d9 e8 6b cf e9 fc c6 05 4b 74 e8 0a 01 90 48 c7 c7
[ 7.446639][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[ 7.446639][ T1] RAX: 97987c7bd8eab100 RBX: ffff8881472d6f6c RCX: ffff8880166d0000
[ 7.446639][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[ 7.446639][ T1] RBP: 0000000000000004 R08: ffffffff81580062 R09: fffffbfff1c396e0
[ 7.446639][ T1] R10: dffffc0000000000 R11: fffffbfff1c396e0 R12: ffffea0000856dc0
[ 7.446639][ T1] R13: ffffea0000856dc8 R14: 1ffffd400010adb9 R15: 0000000000000000
[ 7.446639][ T1] ? __warn_printk+0x292/0x360
[ 7.446639][ T1] ? refcount_warn_saturate+0xf9/0x1d0
[ 7.446639][ T1] __free_pages_ok+0xc60/0xd90
[ 7.446639][ T1] make_alloc_exact+0xa3/0xf0
[ 7.446639][ T1] vring_alloc_queue_split+0x20a/0x600
[ 7.446639][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
[ 7.446639][ T1] ? vp_find_vqs+0x4c/0x4e0
[ 7.446639][ T1] ? virtscsi_probe+0x3ea/0xf60
[ 7.446639][ T1] ? virtio_dev_probe+0x991/0xaf0
[ 7.446639][ T1] ? really_probe+0x2b8/0xad0
[ 7.446639][ T1] ? driver_probe_device+0x50/0x430
[ 7.446639][ T1] vring_create_virtqueue_split+0xc6/0x310
[ 7.446639][ T1] ? ret_from_fork+0x4b/0x80
[ 7.446639][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
[ 7.446639][ T1] vring_create_virtqueue+0xca/0x110
[ 7.446639][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.446639][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.446639][ T1] setup_vq+0xe9/0x2d0
[ 7.446639][ T1] ? __pfx_vp_notify+0x10/0x10
[ 7.446639][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.446639][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.446639][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.446639][ T1] vp_setup_vq+0xbf/0x330
[ 7.446639][ T1] ? __pfx_vp_config_changed+0x10/0x10
[ 7.446639][ T1] ? ioread16+0x2f/0x90
[ 7.446639][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
[ 7.446639][ T1] vp_find_vqs_msix+0x8b2/0xc80
[ 7.446639][ T1] vp_find_vqs+0x4c/0x4e0
[ 7.446639][ T1] virtscsi_init+0x8db/0xd00
[ 7.446639][ T1] ? __pfx_virtscsi_init+0x10/0x10
[ 7.446639][ T1] ? __pfx_default_calc_sets+0x10/0x10
[ 7.446639][ T1] ? scsi_host_alloc+0xa57/0xea0
[ 7.446639][ T1] ? vp_get+0xfd/0x140
[ 7.446639][ T1] virtscsi_probe+0x3ea/0xf60
[ 7.446639][ T1] ? __pfx_virtscsi_probe+0x10/0x10
[ 7.446639][ T1] ? virtio_pci_modern_probe+0x1ad/0x270
[ 7.446639][ T1] ? __pfx_vp_set_status+0x10/0x10
[ 7.446639][ T1] ? vp_set_status+0x1a/0x40
[ 7.446639][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
[ 7.446639][ T1] ? virtio_features_ok+0x10c/0x270
[ 7.446639][ T1] virtio_dev_probe+0x991/0xaf0
[ 7.446639][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 7.446639][ T1] really_probe+0x2b8/0xad0
[ 7.446639][ T1] __driver_probe_device+0x1a2/0x390
[ 7.496320][ T1] driver_probe_device+0x50/0x430
[ 7.496320][ T1] __driver_attach+0x45f/0x710
[ 7.496320][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.496320][ T1] bus_for_each_dev+0x239/0x2b0
[ 7.496320][ T1] ? __pfx___driver_attach+0x10/0x10
[ 7.496320][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 7.496320][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
[ 7.496320][ T1] bus_add_driver+0x347/0x620
[ 7.496320][ T1] driver_register+0x23a/0x320
[ 7.496320][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.496320][ T1] virtio_scsi_init+0x65/0xe0
[ 7.496320][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.496320][ T1] do_one_initcall+0x248/0x880
[ 7.496320][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
[ 7.496320][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 7.496320][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 7.496320][ T1] ? __pfx_parse_args+0x10/0x10
[ 7.496320][ T1] ? do_initcalls+0x1c/0x80
[ 7.496320][ T1] ? rcu_is_watching+0x15/0xb0
[ 7.496320][ T1] do_initcall_level+0x157/0x210
[ 7.496320][ T1] do_initcalls+0x3f/0x80
[ 7.496320][ T1] kernel_init_freeable+0x435/0x5d0
[ 7.496320][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
[ 7.496320][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[ 7.496320][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.496320][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.496320][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.496320][ T1] kernel_init+0x1d/0x2b0
[ 7.496320][ T1] ret_from_fork+0x4b/0x80
[ 7.496320][ T1] ? __pfx_kernel_init+0x10/0x10
[ 7.496320][ T1] ret_from_fork_asm+0x1a/0x30
[ 7.496320][ T1] </TASK>
[ 7.496320][ T1] Kernel Offset: disabled
[ 7.496320][ T1] Rebooting in 86400 seconds..

syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''

GOMODCACHE='/syzkaller/jobs-2/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs-2/linux/gopath'

GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.4'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'

GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod'

GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'

GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build2839934155=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 454571b6a
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=454571b6a16598f5a6e015b9fb1a04932bce7ab9 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240326-163935'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"454571b6a16598f5a6e015b9fb1a04932bce7ab9\"


Error text is too large and was truncated, full error text is at:

https://syzkaller.appspot.com/x/error.txt?x=17196223180000


Tested on:

commit: 1cfa2f10 Merge tag 'for-netdev' of https://git.kernel...
git tree: net
kernel config: https://syzkaller.appspot.com/x/.config?x=7b667bc37450fdcd

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=11cdcca9180000

[Toke Høiland-Jørgensen]

syzbot <syzbot+af9492...@syzkaller.appspotmail.com> writes:

> Hello,
>
> syzbot tried to test the proposed patch but the build/boot failed:

Trying again on a different branch:

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git 443574b03387

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in dev_map_enqueue

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]

CPU: 0 PID: 8787 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller-05236-g443574b03387-dirty #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024

RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539

Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 a6 42 d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 10 8a 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc9000bc1f688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888011815a00
RDX: 0000000000000000 RSI: ffff88802bed7070 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff894ff90e
R10: 0000000000000004 R11: ffff888011815a00 R12: ffff888022f4a000
R13: ffff88802bed7070 R14: dffffc0000000000 R15: ffff8880b943c088
FS: 00007f0b6b2916c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f0b6a5a80c0 CR3: 000000002dad2000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000

DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Call Trace:
<TASK>
__xdp_do_redirect_frame net/core/filter.c:4384 [inline]
xdp_do_redirect_frame+0x20d/0x4d0 net/core/filter.c:4438

xdp_test_run_batch net/bpf/test_run.c:337 [inline]
bpf_test_run_xdp_live+0xf0b/0x1f10 net/bpf/test_run.c:385
bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1268

bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240
__sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75

RIP: 0033:0x7f0b6a47dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0b6b2910c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f0b6a5abf80 RCX: 00007f0b6a47dda9

RDX: 0000000000000050 RSI: 0000000020000240 RDI: 000000000000000a

RBP: 00007f0b6a4ca47a R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 000000000000000b R14: 00007f0b6a5abf80 R15: 00007ffe8c70ed58

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:dev_map_enqueue+0x31/0x3e0 kernel/bpf/devmap.c:539

Code: 41 56 41 55 41 54 53 48 83 ec 18 49 89 d4 49 89 f5 48 89 fd 49 be 00 00 00 00 00 fc ff df e8 a6 42 d8 ff 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 10 8a 3b 00 4c 8b 7d 00 48 83 c5
RSP: 0018:ffffc9000bc1f688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888011815a00
RDX: 0000000000000000 RSI: ffff88802bed7070 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000005 R09: ffffffff894ff90e
R10: 0000000000000004 R11: ffff888011815a00 R12: ffff888022f4a000
R13: ffff88802bed7070 R14: dffffc0000000000 R15: ffff8880b943c088
FS: 00007f0b6b2916c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f0b6a5a80c0 CR3: 000000002dad2000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000

DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

----------------
Code disassembly (best guess):
0: 41 56 push %r14
2: 41 55 push %r13
4: 41 54 push %r12
6: 53 push %rbx
7: 48 83 ec 18 sub $0x18,%rsp
b: 49 89 d4 mov %rdx,%r12
e: 49 89 f5 mov %rsi,%r13
11: 48 89 fd mov %rdi,%rbp
14: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14
1b: fc ff df
1e: e8 a6 42 d8 ff call 0xffd842c9
23: 48 89 e8 mov %rbp,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi
34: e8 10 8a 3b 00 call 0x3b8a49
39: 4c 8b 7d 00 mov 0x0(%rbp),%r15
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c5 .byte 0xc5

Tested on:

commit: 443574b0 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

console output: https://syzkaller.appspot.com/x/log.txt?x=11ac5323180000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440

dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=154653d3180000

[Toke Høiland-Jørgensen]

syzbot <syzbot+af9492...@syzkaller.appspotmail.com> writes:

> Hello,
>
> syzbot has tested the proposed patch but the reproducer is still triggering an issue:
> general protection fault in dev_map_enqueue

Alright, trying a different thing (not a correct patch, just testing a theory):

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git 443574b03387

diff --git a/net/core/filter.c b/net/core/filter.c
index 786d792ac816..c2fd4f67766f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4301,8 +4301,9 @@ void bpf_clear_redirect_map(struct bpf_map *map)
* cmpxchg() to make sure it hasn't been changed in
* the meantime by remote CPU.
*/
- if (unlikely(READ_ONCE(ri->map) == map))
- cmpxchg(&ri->map, map, NULL);
+ if (unlikely(READ_ONCE(ri->map) == map) &&
+ cmpxchg(&ri->map, map, NULL) == map)
+ WRITE_ONCE(ri->map_type, BPF_MAP_TYPE_UNSPEC);
}
}

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+af9492...@syzkaller.appspotmail.com

Tested on:

commit: 443574b0 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

console output: https://syzkaller.appspot.com/x/log.txt?x=125ea0e3180000

kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=156227cd180000

[Toke Høiland-Jørgensen]

And now the real patch:

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git 443574b03387


diff --git a/net/core/filter.c b/net/core/filter.c

index 786d792ac816..8120c3dddf5e 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4363,10 +4363,12 @@ static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
u32 map_id = ri->map_id;
+ u32 flags = ri->flags;
struct bpf_map *map;
int err;

ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
+ ri->flags = 0;
ri->map_type = BPF_MAP_TYPE_UNSPEC;

if (unlikely(!xdpf)) {
@@ -4378,11 +4380,20 @@ static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
case BPF_MAP_TYPE_DEVMAP:
fallthrough;
case BPF_MAP_TYPE_DEVMAP_HASH:
- map = READ_ONCE(ri->map);
- if (unlikely(map)) {
+ if (unlikely(flags & BPF_F_BROADCAST)) {
+ map = READ_ONCE(ri->map);
+
+ /* The map pointer is cleared when the map is being torn
+ * down by bpf_clear_redirect_map()
+ */
+ if (unlikely(!map)) {
+ err = -ENOENT;
+ break;
+ }
+
WRITE_ONCE(ri->map, NULL);

err = dev_map_enqueue_multi(xdpf, dev, map,

- ri->flags & BPF_F_EXCLUDE_INGRESS);
+ flags & BPF_F_EXCLUDE_INGRESS);
} else {

err = dev_map_enqueue(fwd, xdpf, dev);
}

@@ -4445,9 +4456,9 @@ EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
static int xdp_do_generic_redirect_map(struct net_device *dev,
struct sk_buff *skb,
struct xdp_buff *xdp,
- struct bpf_prog *xdp_prog,
- void *fwd,
- enum bpf_map_type map_type, u32 map_id)
+ struct bpf_prog *xdp_prog, void *fwd,
+ enum bpf_map_type map_type, u32 map_id,
+ u32 flags)
{

struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);

struct bpf_map *map;
@@ -4457,11 +4468,20 @@ static int xdp_do_generic_redirect_map(struct net_device *dev,
case BPF_MAP_TYPE_DEVMAP:
fallthrough;
case BPF_MAP_TYPE_DEVMAP_HASH:
- map = READ_ONCE(ri->map);
- if (unlikely(map)) {
+ if (unlikely(flags & BPF_F_BROADCAST)) {
+ map = READ_ONCE(ri->map);
+
+ /* The map pointer is cleared when the map is being torn
+ * down by bpf_clear_redirect_map()
+ */
+ if (unlikely(!map)) {
+ err = -ENOENT;
+ break;
+ }
+
WRITE_ONCE(ri->map, NULL);
err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
- ri->flags & BPF_F_EXCLUDE_INGRESS);
+ flags & BPF_F_EXCLUDE_INGRESS);
} else {
err = dev_map_generic_redirect(fwd, skb, xdp_prog);
}
@@ -4498,9 +4518,11 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
enum bpf_map_type map_type = ri->map_type;
void *fwd = ri->tgt_value;
u32 map_id = ri->map_id;
+ u32 flags = ri->flags;
int err;

ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
+ ri->flags = 0;
ri->map_type = BPF_MAP_TYPE_UNSPEC;

if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
@@ -4520,7 +4542,7 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
return 0;
}

- return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id);
+ return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id, flags);
err:
_trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
return err;

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+af9492...@syzkaller.appspotmail.com

Tested on:

commit: 443574b0 riscv, bpf: Fix kfunc parameters incompatibil..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git

console output: https://syzkaller.appspot.com/x/log.txt?x=15d5b33b180000

kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=af9492708df9797198d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=12bfa653180000