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KCSAN: data-race in atime_needs_update / propagate_one

Status: closed as invalid on 2020/06/18 14:24
Subsystems: ext4
[Documentation on labels]
First crash: 1431d, last: 1373d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in atime_needs_update / propagate_one (2) ext4 96 1071d 1225d 0/26 auto-closed as invalid on 2021/05/17 16:08

Sample crash report:
==================================================================
BUG: KCSAN: data-race in atime_needs_update / propagate_one

write to 0xffff88821b7e46f0 of 4 bytes by task 8920 on cpu 0:
 propagate_one fs/pnode.c:269 [inline]
 propagate_one+0x3b3/0x550 fs/pnode.c:225
 propagate_mnt+0x22e/0x270 fs/pnode.c:320
 attach_recursive_mnt+0x66d/0x8a0 fs/namespace.c:2071
 graft_tree+0x107/0x160 fs/namespace.c:2179
 do_add_mount.isra.0+0x102/0x190 fs/namespace.c:2725
 do_new_mount_fc fs/namespace.c:2764 [inline]
 do_new_mount fs/namespace.c:2818 [inline]
 do_mount+0x12d5/0x1590 fs/namespace.c:3141
 __do_sys_mount fs/namespace.c:3350 [inline]
 __se_sys_mount fs/namespace.c:3327 [inline]
 __x64_sys_mount+0x12b/0x1a0 fs/namespace.c:3327
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88821b7e46f0 of 4 bytes by task 8905 on cpu 1:
 atime_needs_update+0x13e/0x360 fs/inode.c:1726
 touch_atime+0x63/0x150 fs/inode.c:1748
 file_accessed include/linux/fs.h:2226 [inline]
 generic_file_buffered_read mm/filemap.c:2243 [inline]
 generic_file_read_iter+0x12fa/0x18c0 mm/filemap.c:2309
 ext4_file_read_iter fs/ext4/file.c:131 [inline]
 ext4_file_read_iter+0x103/0x360 fs/ext4/file.c:114
 call_read_iter include/linux/fs.h:1901 [inline]
 new_sync_read+0x306/0x450 fs/read_write.c:415
 __vfs_read+0x9e/0xb0 fs/read_write.c:428
 integrity_kernel_read+0x97/0xe0 security/integrity/iint.c:200
 ima_calc_file_hash_tfm+0x18f/0x240 security/integrity/ima/ima_crypto.c:358
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:389 [inline]
 ima_calc_file_hash+0x147/0xeb0 security/integrity/ima/ima_crypto.c:454
 ima_collect_measurement+0x385/0x3b0 security/integrity/ima/ima_api.c:249
 process_measurement+0x91a/0x1000 security/integrity/ima/ima_main.c:324
 ima_file_check+0x7e/0xb0 security/integrity/ima/ima_main.c:440
 do_open fs/namei.c:3231 [inline]
 path_openat+0x176e/0x23d0 fs/namei.c:3346
 do_filp_open+0x11e/0x1b0 fs/namei.c:3373
 do_sys_openat2+0x52e/0x680 fs/open.c:1148
 do_sys_open+0xa2/0x110 fs/open.c:1164
 __do_sys_openat fs/open.c:1178 [inline]
 __se_sys_openat fs/open.c:1173 [inline]
 __x64_sys_openat+0x5d/0x70 fs/open.c:1173
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8905 Comm: syz-fuzzer Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/14 17:34 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2a22c77a .config console log report ci2-upstream-kcsan-gce
2020/06/07 10:06 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2c2b926c .config console log report ci2-upstream-kcsan-gce
2020/06/03 21:47 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a5ce5de0 .config console log report ci2-upstream-kcsan-gce
2020/06/03 00:33 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f3ba1b5b .config console log report ci2-upstream-kcsan-gce
2020/05/25 00:50 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 11284182 .config console log report ci2-upstream-kcsan-gce
2020/05/18 12:11 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 24d91142 .config console log report ci2-upstream-kcsan-gce
2020/05/09 00:29 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e97b06d3 .config console log report ci2-upstream-kcsan-gce
2020/05/01 10:47 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 143a10e9 .config console log report ci2-upstream-kcsan-gce
2020/04/24 12:05 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 03d97a1b .config console log report ci2-upstream-kcsan-gce
2020/04/21 11:18 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f20434a8 .config console log report ci2-upstream-kcsan-gce
2020/04/18 02:54 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 435c6d53 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.