syzbot


BUG: unable to handle kernel NULL pointer dereference in lookup_one_unlocked

Status: upstream: reported C repro on 2024/08/30 03:46
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+1850d38cdeb50dbd013d@syzkaller.appspotmail.com
First crash: 46d, last: 11d
Bug presence (2)
Date Name Commit Repro Result
2024/08/30 upstream (ToT) fb24560f31f9 C [report] BUG: unable to handle kernel NULL pointer dereference in lookup_one_unlocked
2024/10/15 upstream (ToT) eca631b8fe80 C Failed due to an error; will retry later
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/10/04 00:45 11m retest repro linux-5.15.y report log

Sample crash report:
loop0: detected capacity change from 0 to 64
overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off.
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
  ESR = 0x0000000086000006
  EC = 0x21: IABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=000000010a4eb000
[0000000000000000] pgd=080000010a0e3003, p4d=080000010a0e3003, pud=080000010d868003, pmd=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4015 Comm: syz-executor206 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : __lookup_slow+0x250/0x388 fs/namei.c:1663
sp : ffff800018ff7500
x29: ffff800018ff75e0 x28: 0000000010000000 x27: 1fffe0001b04b3ac
x26: dfff800000000000 x25: ffff7000031feea4 x24: ffff800018ff7540
x23: ffff0000dc2c8018 x22: ffff800018ff7660 x21: ffff800011cb6280
x20: 0000000000000000 x19: ffff0000d8259d60 x18: ffff800018ff7060
x17: 0000000000000000 x16: ffff800011aaffbc x15: 000000000000be2d
x14: 00000000b5a9332d x13: dfff800000000000 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : ffff0000c8333680
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff80001777ee20 x4 : 0000000000000000 x3 : ffff8000089e0bd4
x2 : 0000000000000000 x1 : ffff0000d8259d60 x0 : ffff0000dc2c8018
Call trace:
 0x0
 lookup_slow fs/namei.c:1680 [inline]
 lookup_one_unlocked+0x144/0x254 fs/namei.c:2779
 lookup_one_len_unlocked+0x3c/0x50 fs/namei.c:2833
 ovl_lookup_positive_unlocked fs/overlayfs/namei.c:205 [inline]
 ovl_lookup_single+0x84/0x6c4 fs/overlayfs/namei.c:230
 ovl_lookup_layer+0x368/0x454 fs/overlayfs/namei.c:314
 ovl_lookup+0x840/0x1928 fs/overlayfs/namei.c:914
 lookup_one_qstr_excl+0x108/0x230 fs/namei.c:1563
 do_unlinkat+0x2f0/0x830 fs/namei.c:4332
 __do_sys_unlinkat fs/namei.c:4391 [inline]
 __se_sys_unlinkat fs/namei.c:4384 [inline]
 __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4384
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: bad PC value
---[ end trace b93e3b587ae89b38 ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/30 16:26 linux-5.15.y fa93fa65db6e ee2602b8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 BUG: unable to handle kernel NULL pointer dereference in lookup_one_unlocked
2024/08/30 03:46 linux-5.15.y fa93fa65db6e 9bd464fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 BUG: unable to handle kernel NULL pointer dereference in lookup_one_unlocked
* Struck through repros no longer work on HEAD.