Hello, syzbot found the following issue on: HEAD commit: 4d48f589d294 Add linux-next specific files for 20221021 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=165e12da880000 kernel config: https://syzkaller.appspot.com/x/.config?x=2c4b7d600a5739a6 dashboard link: https://syzkaller.appspot.com/bug?extid=a7f196a1dbf5e2c70568 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=11f10ff6880000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145f1ff2880000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/0c86bd0b39a0/disk-4d48f589.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/074059d37f1f/vmlinux-4d48f589.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a7f196a1dbf5e2c70568@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 3609 Comm: syz-executor110 Not tainted 6.1.0-rc1-next-20221021-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 RIP: 0010:strchr+0x17/0xa0 lib/string.c:329 Code: 48 89 34 24 e8 5a 37 82 f8 48 8b 34 24 eb 9a 0f 1f 40 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 48 c1 ea 03 53 48 83 ec 10 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 07 89 RSP: 0018:ffffc90003c3fad0 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: 1ffff92000787f77 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000000000000003a RDI: 0000000000000000 RBP: 1ffff92000787f62 R08: 0000000000000005 R09: 0000000000000009 R10: 0000000000000003 R11: 000000000008c001 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807e7e3b90 R15: dffffc0000000000 FS: 0000555557488300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001000 CR3: 00000000268e7000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> mpol_parse_str+0x79/0xa90 mm/mempolicy.c:2992 shmem_parse_one+0x7d8/0xa60 mm/shmem.c:3508 vfs_parse_fs_param fs/fs_context.c:148 [inline] vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129 vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191 shmem_parse_options+0x15f/0x240 mm/shmem.c:3570 do_new_mount fs/namespace.c:3036 [inline] path_mount+0x12de/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f34b3ddeb19 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffdebbcaee8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f34b3ddeb19 RDX: 0000000020000080 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007f34b3da2cc0 R08: 0000000020000100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f34b3da2d50 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:strchr+0x17/0xa0 lib/string.c:329 Code: 48 89 34 24 e8 5a 37 82 f8 48 8b 34 24 eb 9a 0f 1f 40 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 48 c1 ea 03 53 48 83 ec 10 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 07 89 RSP: 0018:ffffc90003c3fad0 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: 1ffff92000787f77 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000000000000003a RDI: 0000000000000000 RBP: 1ffff92000787f62 R08: 0000000000000005 R09: 0000000000000009 R10: 0000000000000003 R11: 000000000008c001 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807e7e3b90 R15: dffffc0000000000 FS: 0000555557488300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f34b3e51270 CR3: 00000000268e7000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 89 34 24 mov %rsi,(%rsp) 4: e8 5a 37 82 f8 callq 0xf8823763 9: 48 8b 34 24 mov (%rsp),%rsi d: eb 9a jmp 0xffffffa9 f: 0f 1f 40 00 nopl 0x0(%rax) 13: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1a: fc ff df 1d: 48 89 fa mov %rdi,%rdx 20: 55 push %rbp 21: 48 c1 ea 03 shr $0x3,%rdx 25: 53 push %rbx 26: 48 83 ec 10 sub $0x10,%rsp * 2a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction 2e: 48 89 fa mov %rdi,%rdx 31: 83 e2 07 and $0x7,%edx 34: 38 d0 cmp %dl,%al 36: 7f 04 jg 0x3c 38: 84 c0 test %al,%al 3a: 75 51 jne 0x8d 3c: 0f b6 07 movzbl (%rdi),%eax 3f: 89 .byte 0x89 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
