syzbot


KCSAN: data-race in do_sendfile / do_sendfile

Status: auto-closed as invalid on 2022/03/24 16:27
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 308d, last: 293d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_sendfile / do_sendfile (2) 1 108d 108d 0/24 auto-closed as invalid on 2022/09/24 23:59

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

write to 0xffff888105590568 of 8 bytes by task 4934 on cpu 0:
 do_sendfile+0x915/0xc40 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff888105590568 of 8 bytes by task 4970 on cpu 1:
 do_sendfile+0x915/0xc40 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000082 -> 0x000000000000634c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4970 Comm: syz-executor.4 Not tainted 5.17.0-rc4-syzkaller-00054-gf71077a4d84b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/02/17 16:18 upstream f71077a4d84b 2bea8a27 .config log report info KCSAN: data-race in do_sendfile / do_sendfile
ci2-upstream-kcsan-gce 2022/02/02 13:26 upstream 9f7fb8de5d9b 4ebb2798 .config log report info KCSAN: data-race in do_sendfile / do_sendfile
* Struck through repros no longer work on HEAD.