[syzbot] general protection fault in skb_queue_tail (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aaa11ce2ffc8 Add linux-next specific files for 20220923
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=16b08124880000
kernel config: https://syzkaller.appspot.com/x/.config?x=186d1ff305f10294
dashboard link: https://syzkaller.appspot.com/bug?extid=160a7250e255d25725eb
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17b4f3d4880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=160283c0880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/95c7bf83c07e/disk-aaa11ce2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b161cd56a7a3/vmlinux-aaa11ce2.xz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=172283c0880000
final oops: https://syzkaller.appspot.com/x/report.txt?x=14a283c0880000
console output: https://syzkaller.appspot.com/x/log.txt?x=10a283c0880000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+160a72...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 3616 Comm: syz-executor849 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:__skb_insert include/linux/skbuff.h:2158 [inline]
RIP: 0010:__skb_queue_before include/linux/skbuff.h:2264 [inline]
RIP: 0010:__skb_queue_tail include/linux/skbuff.h:2297 [inline]
RIP: 0010:skb_queue_tail+0x9e/0x140 net/core/skbuff.c:3402
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 4c 89 e2 4c 89 65 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 48 89 6b 08 <80> 3c 02 00 75 4f 48 8d 7b 10 49 89 2c 24 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc900000079c0 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff888070c23890 RCX: ffffffff815ffdc0
RDX: 0000000000000000 RSI: 0000000000000046 RDI: ffff888070c30a08
RBP: ffff888070c30a00 R08: 0000000000000001 R09: 0000000000000003
R10: fffff52000000f26 R11: 000000000008c07e R12: 0000000000000000
R13: ffff888070c238a8 R14: 00000000ffff9c2b R15: ffffffff85186a70
FS: 000055555691a300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5ac5d382e8 CR3: 00000000775ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
ath9k_htc_txep+0x287/0x400 drivers/net/wireless/ath/ath9k/htc_drv_txrx.c:712
ath9k_htc_txcompletion_cb+0x1cd/0x2e0 drivers/net/wireless/ath/ath9k/htc_hst.c:353
hif_usb_regout_cb+0x115/0x1c0 drivers/net/wireless/ath/ath9k/hif_usb.c:90
__usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1671
usb_hcd_giveback_urb+0x380/0x430 drivers/usb/core/hcd.c:1754
dummy_timer+0x11ff/0x32c0 drivers/usb/gadget/udc/dummy_hcd.c:1988
call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers.part.0+0x6a2/0xaf0 kernel/time/timer.c:1790
__run_timers kernel/time/timer.c:1768 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
__do_softirq+0x1f7/0xad8 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 ee c3 cf f7 48 89 ef e8 36 30 d0 f7 e8 81 46 f3 f7 fb bf 01 00 00 00 <e8> b6 bb c2 f7 65 8b 05 9f 9e 72 76 85 c0 74 02 5d c3 e8 ce a6 70
RSP: 0018:ffffc90003d0fdc0 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff8880738f9d40 RCX: 1ffffffff1bc50b4
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff88807aec5c80 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed100f5d8b90 R11: 0000000000000001 R12: 0000000000000004
R13: 0000000008000000 R14: 0000000000000000 R15: ffff8880738fa2a0
spin_unlock_irq include/linux/spinlock.h:400 [inline]
ptrace_stop.part.0+0x2f1/0x8c0 kernel/signal.c:2281
ptrace_stop kernel/signal.c:2233 [inline]
ptrace_do_notify+0x215/0x2b0 kernel/signal.c:2345
ptrace_notify+0xc4/0x140 kernel/signal.c:2357
ptrace_report_syscall include/linux/ptrace.h:420 [inline]
ptrace_report_syscall_entry include/linux/ptrace.h:457 [inline]
syscall_trace_enter.constprop.0+0xb0/0x250 kernel/entry/common.c:65
do_syscall_64+0x16/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5ac5d6dc1b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 03 fd ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 41 fd ff ff 8b 44
RSP: 002b:00007ffeb5f65d90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 000000000000001d RCX: 00007f5ac5d6dc1b
RDX: ffffffffffffffb8 RSI: 0000000000000000 RDI: 000000000000001c
RBP: 000000000000015e R08: 0000000000000000 R09: 00007ffeb5f65de0
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f5ac5e3649c
R13: 000000000000b212 R14: 00007f5ac5e36480 R15: 0000000000000004
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__skb_insert include/linux/skbuff.h:2158 [inline]
RIP: 0010:__skb_queue_before include/linux/skbuff.h:2264 [inline]
RIP: 0010:__skb_queue_tail include/linux/skbuff.h:2297 [inline]
RIP: 0010:skb_queue_tail+0x9e/0x140 net/core/skbuff.c:3402
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 4c 89 e2 4c 89 65 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 48 89 6b 08 <80> 3c 02 00 75 4f 48 8d 7b 10 49 89 2c 24 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc900000079c0 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff888070c23890 RCX: ffffffff815ffdc0
RDX: 0000000000000000 RSI: 0000000000000046 RDI: ffff888070c30a08
RBP: ffff888070c30a00 R08: 0000000000000001 R09: 0000000000000003
R10: fffff52000000f26 R11: 000000000008c07e R12: 0000000000000000
R13: ffff888070c238a8 R14: 00000000ffff9c2b R15: ffffffff85186a70
FS: 000055555691a300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5ac5d382e8 CR3: 00000000775ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 48 89 fa mov %rdi,%rdx
3: 48 c1 ea 03 shr $0x3,%rdx
7: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
b: 0f 85 80 00 00 00 jne 0x91
11: 4c 89 e2 mov %r12,%rdx
14: 4c 89 65 08 mov %r12,0x8(%rbp)
18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1f: fc ff df
22: 48 c1 ea 03 shr $0x3,%rdx
26: 48 89 6b 08 mov %rbp,0x8(%rbx)
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 75 4f jne 0x7f
30: 48 8d 7b 10 lea 0x10(%rbx),%rdi
34: 49 89 2c 24 mov %rbp,(%r12)
38: 48 rex.W
39: b8 00 00 00 00 mov $0x0,%eax
3e: 00 fc add %bh,%ah


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[Hillf Danton]

On 12 Oct 2022 07:03:39 -0700

> syzbot found the following issue on:
>
> HEAD commit: aaa11ce2ffc8 Add linux-next specific files for 20220923
> git tree: linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=16b08124880000
> kernel config: https://syzkaller.appspot.com/x/.config?x=186d1ff305f10294
> dashboard link: https://syzkaller.appspot.com/bug?extid=160a7250e255d25725eb
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17b4f3d4880000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=160283c0880000

Check if tx is initialized upon getting queue.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git aaa11ce2ffc8

--- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
@@ -133,6 +133,10 @@ get_htc_epid_queue(struct ath9k_htc_priv
struct ath_common *common = ath9k_hw_common(priv->ah);
struct sk_buff_head *epid_queue = NULL;

+ if (priv->tx.initialized != true)
+ return NULL;
+ smp_rmb();
+
if (epid == priv->mgmt_ep)
epid_queue = &priv->tx.mgmt_ep_queue;
else if (epid == priv->cab_ep)
--

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+160a72...@syzkaller.appspotmail.com

Tested on:

commit: aaa11ce2 Add linux-next specific files for 20220923
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1040fe26880000

kernel config: https://syzkaller.appspot.com/x/.config?x=186d1ff305f10294
dashboard link: https://syzkaller.appspot.com/bug?extid=160a7250e255d25725eb
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=14aae96a880000

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

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 061b0cb9327b80d7a0f63a33e7c3e2a91a71f142
Author: Fedor Pchelkin <pche...@ispras.ru>
Date: Wed May 17 15:03:17 2023 +0000

wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12253b7ca80000
start commit: 98555239e4c3 Merge tag 'arc-6.1-fixes' of git://git.kernel..
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=701f2aae1cb0470e
dashboard link: https://syzkaller.appspot.com/bug?extid=160a7250e255d25725eb
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1482f0b6880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=119e4dce880000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: wifi: ath9k: don't allow to overwrite ENDPOINT0 attributes

[Fedor Pchelkin]

Seems reasonable since the reproducer here manages to modify ENDPOINT0
attrs and this leads to the invalid behaviour in different ways - the one
is this bug and another is the one fixed by the commit which syzbot
bisected. Those attempts to modify ENDPOINT0 are now prohibited with this
commit. So I think the result is correct (apart from that this issue is
not related to afs).