Hello, syzbot found the following issue on: HEAD commit: a92b7d26c743 Merge tag 'drm-fixes-2023-06-23' of git://ano.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16cd10e0a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=24ce1b2abaee24cc dashboard link: https://syzkaller.appspot.com/bug?extid=1d7062c505b34792ef90 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=1066cc77280000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=116850bf280000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f0158c6c02c9/disk-a92b7d26.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/91b4daaa4521/vmlinux-a92b7d26.xz kernel image: https://storage.googleapis.com/syzbot-assets/b5e6c2198af0/bzImage-a92b7d26.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/d48571c9b971/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1d7062c505b34792ef90@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 0 PID: 4987 Comm: udevd Not tainted 6.4.0-rc7-syzkaller-00226-ga92b7d26c743 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 RIP: 0010:fsnotify_parent include/linux/fsnotify.h:62 [inline] RIP: 0010:fsnotify_file include/linux/fsnotify.h:99 [inline] RIP: 0010:fsnotify_perm.part.0+0x12e/0x610 include/linux/fsnotify.h:124 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 75 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 68 48 8d 7b 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 5c 04 00 00 4c 8b 73 28 be 08 00 00 00 4d 8d a6 RSP: 0018:ffffc9000347fa00 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000005 RSI: ffffffff83cbf5e3 RDI: 0000000000000028 RBP: ffff888067875bc0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88802d0722d0 R14: ffff88802d07233c R15: 0000000000010000 FS: 00007f538cf63c80(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9b7c4d8718 CR3: 000000002eb3f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> fsnotify_perm include/linux/fsnotify.h:108 [inline] security_file_open+0x86/0xb0 security/security.c:2801 do_dentry_open+0x575/0x13f0 fs/open.c:907 do_open fs/namei.c:3636 [inline] path_openat+0x1baa/0x2750 fs/namei.c:3791 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1383 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f538cb169a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fff8a905c40 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f538cb169a4 RDX: 0000000000080241 RSI: 00007fff8a906188 RDI: 00000000ffffff9c RBP: 00007fff8a906188 R08: 0000000000000004 R09: 0000000000000001 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000080241 R13: 000056095d45972e R14: 0000000000000001 R15: 000056095e6332c0 </TASK> Modules linked in: ---------------- 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 75 04 00 00 jne 0x486 11: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 18: fc ff df 1b: 48 8b 5d 68 mov 0x68(%rbp),%rbx 1f: 48 8d 7b 28 lea 0x28(%rbx),%rdi 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 5c 04 00 00 jne 0x490 34: 4c 8b 73 28 mov 0x28(%rbx),%r14 38: be 08 00 00 00 mov $0x8,%esi 3d: 4d rex.WRB 3e: 8d .byte 0x8d 3f: a6 cmpsb %es:(%rdi),%ds:(%rsi) --- This report is generated by a bot. 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