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KCSAN: data-race in shmem_file_splice_read / shmem_setattr (5)

Status: auto-obsoleted due to no activity on 2024/03/07 19:19
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+173277c2cd37ddaad093@syzkaller.appspotmail.com
First crash: 77d, last: 77d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in shmem_file_splice_read / shmem_setattr mm 1 294d 294d 0/26 auto-obsoleted due to no activity on 2023/08/03 09:30
upstream KCSAN: data-race in shmem_file_splice_read / shmem_setattr (2) mm 1 258d 258d 0/26 auto-obsoleted due to no activity on 2023/09/08 16:50
upstream KCSAN: data-race in shmem_file_splice_read / shmem_setattr (4) mm 5 120d 131d 0/26 auto-obsoleted due to no activity on 2024/01/24 21:39
upstream KCSAN: data-race in shmem_file_splice_read / shmem_setattr (3) mm 1 216d 216d 0/26 auto-obsoleted due to no activity on 2023/10/20 21:00

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

write to 0xffff888131089b40 of 8 bytes by task 7406 on cpu 1:
 i_size_write include/linux/fs.h:932 [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 0xffff888131089b40 of 8 bytes by task 7404 on cpu 0:
 i_size_read include/linux/fs.h:910 [inline]
 shmem_file_splice_read+0x145/0x600 mm/shmem.c:2961
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x268/0x660 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3b9/0x960 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1356 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1348
 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: 0x00000000000003dc -> 0x000000000000000d

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7404 Comm: syz-executor.2 Not tainted 6.8.0-rc2-syzkaller-00084-g5c24e4e9e708 #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
2024/02/01 19:18 upstream 5c24e4e9e708 81024119 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in shmem_file_splice_read / shmem_setattr
* Struck through repros no longer work on HEAD.