syzbot


BUG: unable to handle kernel NULL pointer dereference in qlink_free (3)

Status: auto-closed as invalid on 2021/10/29 22:01
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+e5965b0559d105044dd4@syzkaller.appspotmail.com
First crash: 1000d, last: 1000d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel NULL pointer dereference in qlink_free tomoyo 1 1549d 1548d 0/26 auto-closed as invalid on 2020/04/29 04:22
upstream BUG: unable to handle kernel NULL pointer dereference in qlink_free (2) fs 2 1316d 1332d 0/26 auto-closed as invalid on 2020/12/17 04:49

Sample crash report:
BUG: kernel NULL pointer dereference, address: 00000000000000c0
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4862 Comm: systemd-udevd Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:qlink_to_object mm/kasan/quarantine.c:129 [inline]
RIP: 0010:qlink_free+0x6/0x40 mm/kasan/quarantine.c:134
Code: 02 00 00 00 45 31 c0 45 31 c9 68 b0 77 c9 81 e8 40 83 98 ff 48 83 c4 08 c3 66 66 2e 0f 1f 84 00 00 00 00 00 48 89 f0 48 89 fe <48> 63 88 c0 00 00 00 48 29 ce 48 89 f1 48 c1 e9 03 48 ba 00 00 00
RSP: 0018:ffffc9000133f890 EFLAGS: 00010286
RAX: 0000000000000000 RBX: f000ff53f000ff53 RCX: ffffea0000000008
RDX: 0000000000000000 RSI: ffff888000000000 RDI: ffff888000000000
RBP: ffff888000000000 R08: ffffffff81396427 R09: ffffffff81c97805
R10: ffffed1002208121 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888155352200 R14: 0000000000000000 R15: ffffea0000000000
FS:  00007fb2c5cf38c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000c0 CR3: 00000000186b0000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 qlist_free_all mm/kasan/quarantine.c:165 [inline]
 kasan_quarantine_reduce+0x151/0x1c0 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2956 [inline]
 slab_alloc mm/slub.c:2964 [inline]
 kmem_cache_alloc+0x1d1/0x340 mm/slub.c:2969
 getname_flags+0xba/0x640 fs/namei.c:138
 user_path_at_empty+0x28/0x50 fs/namei.c:2747
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x102/0x3d0 fs/stat.c:203
 vfs_fstatat fs/stat.c:225 [inline]
 vfs_lstat include/linux/fs.h:3386 [inline]
 __do_sys_newlstat fs/stat.c:380 [inline]
 __se_sys_newlstat+0xab/0x770 fs/stat.c:374
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb2c4b65335
Code: 69 db 2b 00 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 83 ff 01 48 89 f0 77 30 48 89 c7 48 89 d6 b8 06 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 03 f3 c3 90 48 8b 15 31 db 2b 00 f7 d8 64 89
RSP: 002b:00007ffd37f2b7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000006
RAX: ffffffffffffffda RBX: 0000560b0db52e00 RCX: 00007fb2c4b65335
RDX: 00007ffd37f2b7f0 RSI: 00007ffd37f2b7f0 RDI: 0000560b0db51e00
RBP: 00007ffd37f2b8b0 R08: 00007fb2c4e24198 R09: 0000000000001010
R10: 00007fb2c4e23b58 R11: 0000000000000246 R12: 0000560b0db51e00
R13: 0000560b0db51e0c R14: 0000560b0db56365 R15: 0000560b0db5636c
Modules linked in:
CR2: 00000000000000c0
---[ end trace e49cf4bb6273e0c5 ]---
RIP: 0010:qlink_to_object mm/kasan/quarantine.c:129 [inline]
RIP: 0010:qlink_free+0x6/0x40 mm/kasan/quarantine.c:134
Code: 02 00 00 00 45 31 c0 45 31 c9 68 b0 77 c9 81 e8 40 83 98 ff 48 83 c4 08 c3 66 66 2e 0f 1f 84 00 00 00 00 00 48 89 f0 48 89 fe <48> 63 88 c0 00 00 00 48 29 ce 48 89 f1 48 c1 e9 03 48 ba 00 00 00
RSP: 0018:ffffc9000133f890 EFLAGS: 00010286

RAX: 0000000000000000 RBX: f000ff53f000ff53 RCX: ffffea0000000008
RDX: 0000000000000000 RSI: ffff888000000000 RDI: ffff888000000000
RBP: ffff888000000000 R08: ffffffff81396427 R09: ffffffff81c97805
R10: ffffed1002208121 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888155352200 R14: 0000000000000000 R15: ffffea0000000000
FS:  00007fb2c5cf38c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd88732028 CR3: 00000000186b0000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/07/31 22:00 upstream c7d102232649 6c236867 .config console log report info ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in qlink_free
* Struck through repros no longer work on HEAD.