KASAN: use-after-free Read in psock_map_pop

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: dafc674b Linux 4.19.44
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15d4eaf8a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=c8bbe18ba7491e73
dashboard link: https://syzkaller.appspot.com/bug?extid=49725605640d0fdab643
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10b7a99ca00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+497256...@syzkaller.appspotmail.com

IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready
8021q: adding VLAN 0 to HW filter on device batadv0
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x33b2/0x48f0
kernel/locking/lockdep.c:3290
Read of size 8 at addr ffff888094ddf8c8 by task syz-executor.4/8767

CPU: 0 PID: 8767 Comm: syz-executor.4 Not tainted 4.19.44 #16
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report mm/kasan/report.c:412 [inline]
kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
__lock_acquire+0x33b2/0x48f0 kernel/locking/lockdep.c:3290
lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3900
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:168
spin_lock_bh include/linux/spinlock.h:334 [inline]
psock_map_pop.isra.0+0x2d/0x1f0 kernel/bpf/sockmap.c:302
bpf_tcp_remove+0x481/0xa20 kernel/bpf/sockmap.c:366
bpf_tcp_close+0x130/0x390 kernel/bpf/sockmap.c:403
inet_release+0xff/0x1e0 net/ipv4/af_inet.c:428
inet6_release+0x53/0x80 net/ipv6/af_inet6.c:472
__sock_release+0xce/0x2a0 net/socket.c:579
sock_close+0x1b/0x30 net/socket.c:1140
__fput+0x2dd/0x8b0 fs/file_table.c:278
kobject: 'loop2' (00000000f7673045): kobject_uevent_env
____fput+0x16/0x20 fs/file_table.c:309
task_work_run+0x145/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x412b40
kobject: 'loop2' (00000000f7673045): fill_kobj_path: path
= '/devices/virtual/block/loop2'
Code: 01 f0 ff ff 0f 83 10 1b 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f
44 00 00 83 3d 4d 37 64 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff
ff 0f 83 e4 1a 00 00 c3 48 83 ec 08 e8 0a fc ff ff
RSP: 002b:00007ffc759cf938 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000412b40
RDX: 0000001b32a20000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000007410a8
R13: 0000000000000003 R14: 0000000000000000 R15: 000000000073bf0c

Allocated by task 8767:
save_stack+0x45/0xd0 mm/kasan/kasan.c:448
kobject: 'loop3' (000000009db3ec43): kobject_uevent_env
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc mm/kasan/kasan.c:553 [inline]
kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
kmem_cache_alloc_node_trace+0x153/0x720 mm/slab.c:3668
kmalloc_node include/linux/slab.h:553 [inline]
kzalloc_node include/linux/slab.h:720 [inline]
smap_init_psock kernel/bpf/sockmap.c:1636 [inline]
__sock_map_ctx_update_elem.isra.0+0x675/0xdc0 kernel/bpf/sockmap.c:1940
sock_hash_ctx_update_elem.isra.0+0x6c2/0x10d0 kernel/bpf/sockmap.c:2411
sock_hash_update_elem+0x246/0x4b0 kernel/bpf/sockmap.c:2495
map_update_elem+0x791/0xda0 kernel/bpf/syscall.c:818
__do_sys_bpf kernel/bpf/syscall.c:2385 [inline]
__se_sys_bpf kernel/bpf/syscall.c:2356 [inline]
__x64_sys_bpf+0x2ec/0x4c0 kernel/bpf/syscall.c:2356
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 5:
save_stack+0x45/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
__cache_free mm/slab.c:3503 [inline]
kfree+0xcf/0x220 mm/slab.c:3822
smap_gc_work+0x7e5/0xab0 kernel/bpf/sockmap.c:1629
process_one_work+0x989/0x1750 kernel/workqueue.c:2153
worker_thread+0x98/0xe40 kernel/workqueue.c:2296
kthread+0x354/0x420 kernel/kthread.c:246
kobject: 'loop3' (000000009db3ec43): fill_kobj_path: path
= '/devices/virtual/block/loop3'
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:413

The buggy address belongs to the object at ffff888094ddf680
which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 584 bytes inside of
1024-byte region [ffff888094ddf680, ffff888094ddfa80)
The buggy address belongs to the page:
page:ffffea0002537780 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0
compound_mapcount: 0
flags: 0x1fffc0000008100(slab|head)
raw: 01fffc0000008100 ffffea00025f5c08 ffffea0002515188 ffff88812c3f0ac0
raw: 0000000000000000 ffff888094dde000 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff888094ddf780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888094ddf800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff888094ddf880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
kobject: 'loop2' (00000000f7673045): kobject_uevent_env
^
ffff888094ddf900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888094ddf980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12e674a0080000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=49725605640d0fdab643
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10f6e8c3f00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=135eaaa0080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+497256...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x2cb4/0x3ff0 kernel/locking/lockdep.c:3295
Read of size 8 at addr ffff8880aaa858c8 by task syz-executor398/5761

CPU: 1 PID: 5761 Comm: syz-executor398 Not tainted 4.19.211-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]

dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
kasan_report mm/kasan/report.c:412 [inline]
__asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
__lock_acquire+0x2cb4/0x3ff0 kernel/locking/lockdep.c:3295
lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:168
spin_lock_bh include/linux/spinlock.h:334 [inline]
psock_map_pop.constprop.0+0x28/0x1f0 kernel/bpf/sockmap.c:302
bpf_tcp_remove+0x47d/0xa00 kernel/bpf/sockmap.c:366
bpf_tcp_close+0x12b/0x390 kernel/bpf/sockmap.c:403
inet_release+0xd7/0x1e0 net/ipv4/af_inet.c:427
__sock_release+0xcd/0x2a0 net/socket.c:599
sock_close+0x15/0x20 net/socket.c:1214
__fput+0x2ce/0x890 fs/file_table.c:278
task_work_run+0x148/0x1c0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xbf3/0x2be0 kernel/exit.c:870
do_group_exit+0x125/0x310 kernel/exit.c:967
__do_sys_exit_group kernel/exit.c:978 [inline]
__se_sys_exit_group kernel/exit.c:976 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:976
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f393e7f36a9
Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00
RSP: 002b:00007ffc20c685a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f393e867310 RCX: 00007f393e7f36a9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 00007ffc20c68630
R10: 00007ffc20c68630 R11: 0000000000000246 R12: 00007f393e867310
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001

Allocated by task 5761:
kmem_cache_alloc_node_trace+0x151/0x3b0 mm/slab.c:3668

kmalloc_node include/linux/slab.h:553 [inline]
kzalloc_node include/linux/slab.h:720 [inline]
smap_init_psock kernel/bpf/sockmap.c:1636 [inline]

__sock_map_ctx_update_elem.constprop.0+0x366/0xea0 kernel/bpf/sockmap.c:1940
sock_hash_ctx_update_elem.isra.0+0x69d/0x1100 kernel/bpf/sockmap.c:2411
sock_hash_update_elem+0x210/0x480 kernel/bpf/sockmap.c:2495
map_update_elem kernel/bpf/syscall.c:821 [inline]
__do_sys_bpf kernel/bpf/syscall.c:2414 [inline]
__se_sys_bpf+0x2cf1/0x3a20 kernel/bpf/syscall.c:2384
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8184:
__cache_free mm/slab.c:3503 [inline]
kfree+0xcc/0x210 mm/slab.c:3822
process_one_work+0x864/0x1570 kernel/workqueue.c:2153
worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff8880aaa85680

which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 584 bytes inside of

1024-byte region [ffff8880aaa85680, ffff8880aaa85a80)

The buggy address belongs to the page:

page:ffffea0002aaa100 count:1 mapcount:0 mapping:ffff88813bff0ac0 index:0xffff8880aaa84900 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea00024cf108 ffffea00026d5c08 ffff88813bff0ac0
raw: ffff8880aaa84900 ffff8880aaa84000 0000000100000003 0000000000000000

page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff8880aaa85780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880aaa85800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880aaa85880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880aaa85900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880aaa85980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================