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KCSAN: data-race in shmem_file_read_iter / shmem_setattr (7)

Status: auto-obsoleted due to no activity on 2023/02/11 12:28
Subsystems: mm
[Documentation on labels]
First crash: 664d, last: 640d
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 509d 557d 0/28 auto-obsoleted due to no activity on 2023/06/17 08:48
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (9) mm 1 216d 216d 0/28 auto-obsoleted due to no activity on 2024/04/05 18:31
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (2) mm 1 1242d 1242d 0/28 auto-closed as invalid on 2021/06/14 12:51
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (5) mm 1 762d 762d 0/28 auto-closed as invalid on 2022/10/07 03:18
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (4) mm 3 822d 826d 0/28 auto-closed as invalid on 2022/08/08 10:34
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr (6) mm 2 705d 708d 0/28 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 1092d 1092d 0/28 auto-closed as invalid on 2021/11/11 20:26
upstream KCSAN: data-race in shmem_file_read_iter / shmem_setattr mm 3 1350d 1385d 0/28 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 0xffff88813f7959e8 of 8 bytes by task 28293 on cpu 1:
 i_size_write include/linux/fs.h:886 [inline]
 shmem_setattr+0x372/0x490 mm/shmem.c:1112
 notify_change+0xa5c/0xad0 fs/attr.c:482
 do_truncate+0xfa/0x140 fs/open.c:65
 do_sys_ftruncate+0x28a/0x380 fs/open.c:193
 __do_sys_ftruncate fs/open.c:204 [inline]
 __se_sys_ftruncate fs/open.c:202 [inline]
 __x64_sys_ftruncate+0x2f/0x40 fs/open.c:202
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813f7959e8 of 8 bytes by task 28292 on cpu 0:
 i_size_read include/linux/fs.h:864 [inline]
 shmem_file_read_iter+0x440/0x580 mm/shmem.c:2616
 call_read_iter include/linux/fs.h:2180 [inline]
 generic_file_splice_read+0xde/0x2b0 fs/splice.c:309
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000001000000 -> 0x0000000000000086

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28292 Comm: syz-executor.5 Not tainted 6.2.0-rc1-syzkaller-00095-ge4cf7c25bae5-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/02 04:31 upstream e4cf7c25bae5 ab32d508 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shmem_file_read_iter / shmem_setattr
2022/12/09 14:32 upstream 0d1409e4ff08 67be1ae7 .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.