On Sun, Oct 13, 2024 at 7:51 PM Lai, Yi <yi1.lai@xxxxxxxxxxxxxxx> wrote: > > Hi Andrii Nakryiko, > > Greetings! > > I used Syzkaller and found that there is BUG: unable to handle kernel paging request in build_id_parse_nofault > This is a memfd_secret() file, which needs a special treatment, I'll post a fix soon, thanks for reporting! > After bisection and the first bad commit is: > " > 45b8fc309654 lib/buildid: rename build_id_parse() into build_id_parse_nofault() > " > > All detailed into can be found at: > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault > Syzkaller repro code: > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault/repro.c > Syzkaller repro syscall steps: > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault/repro.prog > Syzkaller report: > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault/repro.report > Kconfig(make olddefconfig): > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault/kconfig_origin > Bisect info: > https://github.com/laifryiee/syzkaller_logs/tree/main/241012_225717_build_id_parse_nofault/bisect_info.log > bzImage: > https://github.com/laifryiee/syzkaller_logs/raw/refs/heads/main/241012_225717_build_id_parse_nofault/bzImage_8cf0b93919e13d1e8d4466eb4080a4c4d9d66d7b > Issue dmesg: > https://github.com/laifryiee/syzkaller_logs/blob/main/241012_225717_build_id_parse_nofault/8cf0b93919e13d1e8d4466eb4080a4c4d9d66d7b_dmesg.log > > " > [ 26.168603] ? __pfx___build_id_parse.isra.0+0x10/0x10 > [ 26.169447] ? __pfx_d_path+0x10/0x10 > [ 26.170068] ? __kasan_kmalloc+0x88/0xa0 > [ 26.170743] build_id_parse_nofault+0x4d/0x60 > [ 26.171473] perf_event_mmap+0xb44/0xd90 > [ 26.172134] ? __pfx_perf_event_mmap+0x10/0x10 > [ 26.172895] mmap_region+0x4e7/0x29d0 > [ 26.173526] ? __pfx_mmap_region+0x10/0x10 > [ 26.174210] ? lockdep_hardirqs_on+0x89/0x110 > [ 26.174956] ? __kasan_check_read+0x15/0x20 > [ 26.175655] ? mark_lock.part.0+0xf3/0x17b0 > [ 26.176369] ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30 > [ 26.177277] ? arch_get_unmapped_area_topdown+0x3d6/0x710 > [ 26.178195] ? rcu_read_unlock+0x3b/0xc0 > [ 26.178879] ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20 > [ 26.179808] ? __sanitizer_cov_trace_cmp8+0x1c/0x30 > [ 26.180634] ? cap_mmap_addr+0x60/0x330 > [ 26.181300] ? security_mmap_addr+0x63/0x1b0 > [ 26.182029] ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30 > [ 26.182930] ? __get_unmapped_area+0x1a9/0x3b0 > [ 26.183705] do_mmap+0xd9b/0x11f0 > [ 26.184291] ? __pfx_do_mmap+0x10/0x10 > [ 26.184938] ? __pfx_down_write_killable+0x10/0x10 > [ 26.185758] vm_mmap_pgoff+0x1ea/0x390 > [ 26.186413] ? __pfx_vm_mmap_pgoff+0x10/0x10 > [ 26.187129] ? __fget_files+0x23c/0x4b0 > [ 26.187803] ksys_mmap_pgoff+0x3dc/0x520 > [ 26.188490] __x64_sys_mmap+0x139/0x1d0 > [ 26.189143] x64_sys_call+0x18c6/0x20d0 > [ 26.189805] do_syscall_64+0x6d/0x140 > [ 26.190425] entry_SYSCALL_64_after_hwframe+0x76/0x7e > [ 26.191238] RIP: 0033:0x7fb10be3ee5d > [ 26.191837] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d 93 af 1b 00 f7 d8 64 89 01 48 > [ 26.194753] RSP: 002b:00007ffe95b14e28 EFLAGS: 00000212 ORIG_RAX: 0000000000000009 > [ 26.195976] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb10be3ee5d > [ 26.197126] RDX: 0000000000000001 RSI: 0000000000002000 RDI: 0000000020000000 > [ 26.198282] RBP: 00007ffe95b14f50 R08: 0000000000000004 R09: 0000000000000000 > [ 26.199471] R10: 0000000000000011 R11: 0000000000000212 R12: 00007ffe95b150a8 > [ 26.200606] R13: 0000000000402eb7 R14: 0000000000404e08 R15: 00007fb10c078000 > [ 26.201757] </TASK> > [ 26.202132] Modules linked in: > [ 26.202663] CR2: ffff888010a44000 > [ 26.203219] ---[ end trace 0000000000000000 ]--- > [ 26.204002] RIP: 0010:memcmp+0x32/0x50 > [ 26.204685] Code: 06 48 39 07 75 17 48 83 c7 08 48 83 c6 08 48 83 ea 08 48 83 fa 07 77 e6 48 85 d2 74 20 31 c9 eb 09 48 83 c1 01 48 39 ca 74 0e <0f> b6 04 0f 44 0f b6 04 0e 44 29 c0 74 e9 c3 cc cc cc cc 31 c0 c3 > [ 26.207669] RSP: 0018:ffff88801fa675f0 EFLAGS: 00010246 > [ 26.208529] RAX: 0000000000000000 RBX: ffff88801fa67728 RCX: 0000000000000000 > [ 26.209655] RDX: 0000000000000004 RSI: ffffffff86583240 RDI: ffff888010a44000 > [ 26.210801] RBP: ffff88801fa67750 R08: 0000000000000000 R09: fffff94000085220 > [ 26.211929] R10: 0000000000000012 R11: 0000000000000001 R12: ffff888010a17c00 > [ 26.213053] R13: ffff888010a44000 R14: dffffc0000000000 R15: 0000000000000000 > [ 26.214186] FS: 00007fb10c02d800(0000) GS:ffff88806c500000(0000) knlGS:0000000000000000 > [ 26.215467] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 26.216393] CR2: ffff888010a44000 CR3: 00000000124e8000 CR4: 0000000000750ef0 > [ 26.217533] PKRU: 55555554 > [ 26.217989] note: repro[728] exited with irqs disabled > " > > I hope you find it useful. > > Regards, > Yi Lai > > --- > [...]