syzbot


KCSAN: data-race in copy_process / show_stat (3)

Status: auto-closed as invalid on 2022/07/28 00:27
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 167d, last: 167d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in copy_process / show_stat (2) 2 774d 777d 0/24 auto-closed as invalid on 2020/11/28 01:56
upstream KCSAN: data-race in copy_process / show_stat 3 812d 850d 0/24 auto-closed as invalid on 2020/10/21 12:32

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

read-write to 0xffffffff86e4a868 of 8 bytes by task 1841 on cpu 0:
 copy_process+0x1f67/0x20b0 kernel/fork.c:2458
 kernel_clone+0x163/0x5c0 kernel/fork.c:2655
 __do_sys_clone kernel/fork.c:2789 [inline]
 __se_sys_clone kernel/fork.c:2773 [inline]
 __x64_sys_clone+0xc3/0xf0 kernel/fork.c:2773
 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+0x46/0xb0

read to 0xffffffff86e4a868 of 8 bytes by task 16138 on cpu 1:
 show_stat+0xcff/0xe60 fs/proc/stat.c:207
 seq_read_iter+0x2c3/0x8e0 fs/seq_file.c:230
 proc_reg_read_iter+0xd4/0x170 fs/proc/inode.c:296
 call_read_iter include/linux/fs.h:2052 [inline]
 io_iter_do_read fs/io_uring.c:4245 [inline]
 io_read fs/io_uring.c:4364 [inline]
 io_issue_sqe+0x238a/0xaa00 fs/io_uring.c:8325
 io_queue_sqe fs/io_uring.c:8709 [inline]
 io_submit_sqe+0x2e0f/0x3f30 fs/io_uring.c:8973
 io_submit_sqes+0x27b/0x500 fs/io_uring.c:9084
 __do_sys_io_uring_enter fs/io_uring.c:12031 [inline]
 __se_sys_io_uring_enter+0x24b/0xd60 fs/io_uring.c:11957
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:11957
 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+0x46/0xb0

value changed: 0x0000000000003f05 -> 0x0000000000003f06

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16138 Comm: syz-executor.0 Not tainted 5.19.0-rc3-syzkaller-00043-g3abc3ae553c7-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/06/23 00:26 upstream 3abc3ae553c7 912f5df7 .config log report info KCSAN: data-race in copy_process / show_stat
* Struck through repros no longer work on HEAD.