[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 74.606150] audit: type=1800 audit(1548649611.659:25): pid=10095 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 74.625319] audit: type=1800 audit(1548649611.669:26): pid=10095 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 74.644740] audit: type=1800 audit(1548649611.679:27): pid=10095 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.68' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 97.767878] ================================================================== [ 97.775270] BUG: KMSAN: kernel-infoleak in copyout+0x16b/0x1f0 [ 97.781224] CPU: 1 PID: 10345 Comm: blkid Not tainted 5.0.0-rc1+ #7 [ 97.787610] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.796946] Call Trace: [ 97.799650] dump_stack+0x173/0x1d0 [ 97.803272] kmsan_report+0x12e/0x2a0 [ 97.807062] kmsan_internal_check_memory+0x9e4/0xb10 [ 97.812159] kmsan_copy_to_user+0xab/0xc0 [ 97.816294] copyout+0x16b/0x1f0 [ 97.819652] copy_page_to_iter+0x654/0x17e0 [ 97.823976] generic_file_read_iter+0x2f2c/0x4620 [ 97.828822] ? kmsan_get_shadow_origin_ptr+0x60/0x440 [ 97.834017] blkdev_read_iter+0x20d/0x270 [ 97.838164] ? blkdev_write_iter+0x650/0x650 [ 97.842585] __vfs_read+0x94e/0xbf0 [ 97.846218] vfs_read+0x359/0x6f0 [ 97.849666] __se_sys_read+0x17a/0x370 [ 97.853544] __x64_sys_read+0x4a/0x70 [ 97.857328] do_syscall_64+0xbc/0xf0 [ 97.861028] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 97.866203] RIP: 0033:0x7f73fc0b0310 [ 97.869898] Code: 73 01 c3 48 8b 0d 28 4b 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d e5 a2 2b 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 6e 8a 01 00 48 89 04 24 [ 97.888780] RSP: 002b:00007ffdcc737148 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 97.896629] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f73fc0b0310 [ 97.903888] RDX: 0000000000000100 RSI: 0000000002348df8 RDI: 0000000000000003 [ 97.911139] RBP: 0000000002348dd0 R08: 0000000000000028 R09: 0000000001680000 [ 97.918390] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002348030 [ 97.925811] R13: 0000000000000100 R14: 0000000002348080 R15: 0000000002348de8 [ 97.933069] [ 97.934674] Uninit was created at: [ 97.938204] kmsan_save_stack_with_flags+0x7a/0x130 [ 97.943215] kmsan_internal_alloc_meta_for_pages+0x113/0x580 [ 97.948997] kmsan_alloc_page+0x7e/0x100 [ 97.953045] __alloc_pages_nodemask+0x137b/0x5e30 [ 97.957868] alloc_pages_current+0x69d/0x9b0 [ 97.962254] __page_cache_alloc+0x95/0x320 [ 97.966466] pagecache_get_page+0x4f4/0x1300 [ 97.970866] grab_cache_page_write_begin+0x100/0x180 [ 97.975951] block_write_begin+0x102/0x3c0 [ 97.980164] blkdev_write_begin+0xf5/0x110 [ 97.984385] generic_perform_write+0x412/0x990 [ 97.988965] __generic_file_write_iter+0x422/0xa30 [ 97.993940] blkdev_write_iter+0x3f0/0x650 [ 97.998161] __vfs_write+0x98a/0xc20 [ 98.001867] vfs_write+0x481/0x920 [ 98.005386] __se_sys_write+0x17a/0x370 [ 98.009353] __x64_sys_write+0x4a/0x70 [ 98.013219] do_syscall_64+0xbc/0xf0 [ 98.016911] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 98.022079] [ 98.023689] Bytes 8-255 of 256 are uninitialized [ 98.028421] Memory access of size 256 starts at ffff8880a7e58000 [ 98.034542] Data copied to user address 0000000002348df8 [ 98.039966] ================================================================== [ 98.047307] Disabling lock debugging due to kernel taint [ 98.052823] Kernel panic - not syncing: panic_on_warn set ... [ 98.058692] CPU: 1 PID: 10345 Comm: blkid Tainted: G B 5.0.0-rc1+ #7 [ 98.066466] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 98.075800] Call Trace: [ 98.078375] dump_stack+0x173/0x1d0 [ 98.081985] panic+0x3d1/0xb01 [ 98.085178] kmsan_report+0x293/0x2a0 [ 98.088972] kmsan_internal_check_memory+0x9e4/0xb10 [ 98.094068] kmsan_copy_to_user+0xab/0xc0 [ 98.098205] copyout+0x16b/0x1f0 [ 98.101561] copy_page_to_iter+0x654/0x17e0 [ 98.105875] generic_file_read_iter+0x2f2c/0x4620 [ 98.110724] ? kmsan_get_shadow_origin_ptr+0x60/0x440 [ 98.115898] blkdev_read_iter+0x20d/0x270 [ 98.120029] ? blkdev_write_iter+0x650/0x650 [ 98.124419] __vfs_read+0x94e/0xbf0 [ 98.128044] vfs_read+0x359/0x6f0 [ 98.131485] __se_sys_read+0x17a/0x370 [ 98.135362] __x64_sys_read+0x4a/0x70 [ 98.139151] do_syscall_64+0xbc/0xf0 [ 98.142871] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 98.148267] RIP: 0033:0x7f73fc0b0310 [ 98.151964] Code: 73 01 c3 48 8b 0d 28 4b 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d e5 a2 2b 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 6e 8a 01 00 48 89 04 24 [ 98.170851] RSP: 002b:00007ffdcc737148 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 98.178541] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f73fc0b0310 [ 98.185790] RDX: 0000000000000100 RSI: 0000000002348df8 RDI: 0000000000000003 [ 98.193058] RBP: 0000000002348dd0 R08: 0000000000000028 R09: 0000000001680000 [ 98.200308] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002348030 [ 98.207558] R13: 0000000000000100 R14: 0000000002348080 R15: 0000000002348de8 [ 98.215812] Kernel Offset: disabled [ 98.219443] Rebooting in 86400 seconds..