[v5.15] general protection fault in security_inode_getattr (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b95c01af2113 Linux 5.15.152
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11e2fac9180000
kernel config: https://syzkaller.appspot.com/x/.config?x=b26cb65e5b8ad5c7
dashboard link: https://syzkaller.appspot.com/bug?extid=861954e35c7877029cde
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/5cd4262a21bb/disk-b95c01af.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/85698e4f8310/vmlinux-b95c01af.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f57a616768d4/bzImage-b95c01af.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+861954...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
CPU: 0 PID: 6630 Comm: syz-executor.1 Not tainted 5.15.152-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:d_backing_inode include/linux/dcache.h:553 [inline]
RIP: 0010:security_inode_getattr+0x42/0x120 security/security.c:1346
Code: be fd 49 8d 5f 08 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 1c 2d 08 fe 48 8b 2b 48 83 c5 68 48 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 ef e8 ff 2c 08 fe 48 8b 6d 00 48 83 c5
RSP: 0018:ffffc900031c7180 EFLAGS: 00010202
RAX: 000000000000000d RBX: ffffc900031c75f8 RCX: 0000000000040000
RDX: ffffc900145ea000 RSI: 0000000000000632 RDI: 0000000000000633
RBP: 0000000000000068 R08: dffffc0000000000 R09: ffffc900031c75f0
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffc900031c7600 R14: 0000000000000000 R15: ffffc900031c75f0
FS: 00007f883521f6c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f883521fd58 CR3: 00000000abfd2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000063 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
vfs_getattr+0x26/0x360 fs/stat.c:157
ovl_copy_up_one fs/overlayfs/copy_up.c:961 [inline]
ovl_copy_up_flags+0x5e7/0x2e00 fs/overlayfs/copy_up.c:1047
ovl_maybe_copy_up+0x14e/0x180 fs/overlayfs/copy_up.c:1079
ovl_open+0xa4/0x200 fs/overlayfs/file.c:149
do_dentry_open+0x807/0xfb0 fs/open.c:826
do_open fs/namei.c:3608 [inline]
path_openat+0x2702/0x2f20 fs/namei.c:3742
do_filp_open+0x21c/0x460 fs/namei.c:3769
do_sys_openat2+0x13b/0x500 fs/open.c:1211
do_sys_open fs/open.c:1227 [inline]
__do_sys_openat fs/open.c:1243 [inline]
__se_sys_openat fs/open.c:1238 [inline]
__x64_sys_openat+0x243/0x290 fs/open.c:1238
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+0x61/0xcb
RIP: 0033:0x7f8836cbfda9
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:00007f883521f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8836dee050 RCX: 00007f8836cbfda9
RDX: 0000000000000091 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007f8836d0c47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f8836dee050 R15: 00007ffe6e897e08
</TASK>
Modules linked in:
---[ end trace dd228f6e7b8d1e4c ]---
RIP: 0010:d_backing_inode include/linux/dcache.h:553 [inline]
RIP: 0010:security_inode_getattr+0x42/0x120 security/security.c:1346
Code: be fd 49 8d 5f 08 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 1c 2d 08 fe 48 8b 2b 48 83 c5 68 48 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 ef e8 ff 2c 08 fe 48 8b 6d 00 48 83 c5
RSP: 0018:ffffc900031c7180 EFLAGS: 00010202
RAX: 000000000000000d RBX: ffffc900031c75f8 RCX: 0000000000040000
RDX: ffffc900145ea000 RSI: 0000000000000632 RDI: 0000000000000633
RBP: 0000000000000068 R08: dffffc0000000000 R09: ffffc900031c75f0
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffc900031c7600 R14: 0000000000000000 R15: ffffc900031c75f0
FS: 00007f883521f6c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000abfd2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000063 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: be fd 49 8d 5f mov $0x5f8d49fd,%esi
5: 08 48 89 or %cl,-0x77(%rax)
8: d8 48 c1 fmuls -0x3f(%rax)
b: e8 03 42 80 3c call 0x3c804213
10: 20 00 and %al,(%rax)
12: 74 08 je 0x1c
14: 48 89 df mov %rbx,%rdi
17: e8 1c 2d 08 fe call 0xfe082d38
1c: 48 8b 2b mov (%rbx),%rbp
1f: 48 83 c5 68 add $0x68,%rbp
23: 48 89 e8 mov %rbp,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi
34: e8 ff 2c 08 fe call 0xfe082d38
39: 48 8b 6d 00 mov 0x0(%rbp),%rbp
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c5 .byte 0xc5


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