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KCSAN: data-race in shmem_file_read_iter / shmem_setattr (9)

Status: auto-obsoleted due to no activity on 2024/04/05 18:31
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+5ea14eed4d29c47f0456@syzkaller.appspotmail.com
First crash: 115d, last: 115d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (8) mm 5 408d 456d 0/27 auto-obsoleted due to no activity on 2023/06/17 08:48
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (7) mm 2 539d 563d 0/27 auto-obsoleted due to no activity on 2023/02/11 12:28
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (2) mm 1 1141d 1141d 0/27 auto-closed as invalid on 2021/06/14 12:51
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (5) mm 1 662d 662d 0/27 auto-closed as invalid on 2022/10/07 03:18
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (4) mm 3 721d 725d 0/27 auto-closed as invalid on 2022/08/08 10:34
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (6) mm 2 604d 607d 0/27 auto-obsoleted due to no activity on 2022/12/04 01:06
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (3) mm 1 991d 991d 0/27 auto-closed as invalid on 2021/11/11 20:26
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr mm 3 1249d 1284d 0/27 auto-closed as invalid on 2021/02/26 05:27

Sample crash report:
==================================================================
BUG: KCSAN: data-race in shmem_file_read_iter / shmem_setattr

write to 0xffff888139dd5e30 of 8 bytes by task 7621 on cpu 0:
 i_size_write include/linux/fs.h:934 [inline]
 shmem_setattr+0x6fb/0x830 mm/shmem.c:1186
 notify_change+0x866/0x8e0 fs/attr.c:499
 do_truncate+0x116/0x150 fs/open.c:66
 do_sys_ftruncate+0x2ba/0x3b0 fs/open.c:194
 __do_sys_ftruncate fs/open.c:205 [inline]
 __se_sys_ftruncate fs/open.c:203 [inline]
 __x64_sys_ftruncate+0x33/0x40 fs/open.c:203
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888139dd5e30 of 8 bytes by task 7627 on cpu 1:
 i_size_read include/linux/fs.h:912 [inline]
 shmem_file_read_iter+0x96/0x550 mm/shmem.c:2777
 call_read_iter include/linux/fs.h:2081 [inline]
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x5ab/0x6a0 fs/read_write.c:476
 ksys_read+0xeb/0x1a0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:627
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0x0000000002007fff

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7627 Comm: syz-executor.2 Not tainted 6.8.0-rc6-syzkaller-00120-g87adedeba51a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/01 18:30 upstream 87adedeba51a 83acf9e0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shmem_file_read_iter / shmem_setattr
* Struck through repros no longer work on HEAD.