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KCSAN: data-race in generic_file_read_iter / truncate_setsize (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: fs
[Documentation on labels]
First crash: 1543d, last: 1404d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_file_read_iter / truncate_setsize fs 3 1604d 1615d 0/26 closed as invalid on 2019/11/19 13:54

Sample crash report:
==================================================================
BUG: KCSAN: data-race in generic_file_read_iter / truncate_setsize

write to 0xffff8880b5d01770 of 8 bytes by task 16651 on cpu 1:
 i_size_write include/linux/fs.h:894 [inline]
 truncate_setsize+0x34/0x80 mm/truncate.c:839
 simple_setattr+0xb1/0xc0 fs/libfs.c:503
 notify_change+0x82b/0xad0 fs/attr.c:336
 do_truncate+0xf9/0x180 fs/open.c:64
 handle_truncate fs/namei.c:2887 [inline]
 do_open fs/namei.c:3233 [inline]
 path_openat+0x1e51/0x23d0 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
 ksys_open include/linux/syscalls.h:1386 [inline]
 __do_sys_creat fs/open.c:1232 [inline]
 __se_sys_creat fs/open.c:1230 [inline]
 __x64_sys_creat+0x42/0x60 fs/open.c:1230
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880b5d01770 of 8 bytes by task 16635 on cpu 0:
 generic_file_buffered_read mm/filemap.c:2091 [inline]
 generic_file_read_iter+0x85b/0x18c0 mm/filemap.c:2309
 call_read_iter include/linux/fs.h:1901 [inline]
 generic_file_splice_read+0x2df/0x470 fs/splice.c:313
 do_splice_to+0xc7/0x100 fs/splice.c:892
 splice_direct_to_actor+0x1b9/0x540 fs/splice.c:971
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1576 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0xb8/0x140 fs/read_write.c:1568
 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: 0 PID: 16635 Comm: syz-executor.2 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/24 01:58 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 96c92ad3 .config console log report ci2-upstream-kcsan-gce
2020/05/04 07:21 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 58ae5e18 .config console log report ci2-upstream-kcsan-gce
2020/02/25 14:56 https://github.com/google/ktsan.git kcsan 766d004d1b85 4c886d6a .config console log report ci2-upstream-kcsan-gce
2020/01/06 02:18 https://github.com/google/ktsan.git kcsan 245a43005292 438e1227 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.