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KCSAN: data-race in filemap_read / simple_write_end (4)

Status: auto-obsoleted due to no activity on 2023/05/05 08:51
Subsystems: fs
[Documentation on labels]
First crash: 413d, last: 397d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in filemap_read / simple_write_end (2) fs 15 874d 946d 0/26 auto-closed as invalid on 2022/01/13 14:25
upstream KCSAN: data-race in filemap_read / simple_write_end (3) fs 1 527d 527d 0/26 auto-obsoleted due to no activity on 2023/01/02 10:55
upstream KCSAN: data-race in filemap_read / simple_write_end fs 52 1013d 1029d 0/26 auto-closed as invalid on 2021/08/27 20:52

Sample crash report:
==================================================================
BUG: KCSAN: data-race in filemap_read / simple_write_end

write to 0xffff88810a90a2f8 of 8 bytes by task 19810 on cpu 1:
 i_size_write include/linux/fs.h:888 [inline]
 simple_write_end+0x22d/0x410 fs/libfs.c:619
 generic_perform_write+0x253/0x3d0 mm/filemap.c:3937
 __generic_file_write_iter+0xe6/0x290 mm/filemap.c:4054
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4086
 do_iter_write+0x418/0x700 fs/read_write.c:861
 vfs_iter_write+0x50/0x70 fs/read_write.c:902
 iter_file_splice_write+0x456/0x7d0 fs/splice.c:778
 do_splice_from fs/splice.c:856 [inline]
 direct_splice_actor+0x84/0xa0 fs/splice.c:1022
 splice_direct_to_actor+0x2ee/0x5f0 fs/splice.c:977
 do_splice_direct+0x104/0x180 fs/splice.c:1065
 do_sendfile+0x3b8/0x950 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+0x110/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88810a90a2f8 of 8 bytes by task 19820 on cpu 0:
 i_size_read include/linux/fs.h:866 [inline]
 filemap_read+0x247/0x680 mm/filemap.c:2706
 generic_file_read_iter+0x76/0x320 mm/filemap.c:2840
 call_read_iter include/linux/fs.h:1845 [inline]
 generic_file_splice_read+0xe3/0x290 fs/splice.c:402
 do_splice_to fs/splice.c:885 [inline]
 splice_direct_to_actor+0x25a/0x5f0 fs/splice.c:956
 do_splice_direct+0x104/0x180 fs/splice.c:1065
 do_sendfile+0x3b8/0x950 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+0x110/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000241 -> 0x0000000000000242

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19820 Comm: syz-executor.5 Not tainted 6.3.0-rc4-syzkaller-00161-g62bad54b26db #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/31 08:45 upstream 62bad54b26db f325deb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_read / simple_write_end
2023/03/16 04:26 upstream 9c1bec9c0b08 18b58603 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_read / simple_write_end
* Struck through repros no longer work on HEAD.