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KCSAN: data-race in do_epoll_ctl / do_epoll_ctl (4)

Status: auto-obsoleted due to no activity on 2023/07/22 09:13
Subsystems: fs
[Documentation on labels]
First crash: 319d, last: 319d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_epoll_ctl / do_epoll_ctl (2) fs 1 794d 794d 0/26 auto-closed as invalid on 2022/04/03 20:50
upstream KCSAN: data-race in do_epoll_ctl / do_epoll_ctl (5) fs 1 44d 44d 0/26 auto-obsoleted due to no activity on 2024/04/22 09:35
upstream KCSAN: data-race in do_epoll_ctl / do_epoll_ctl fs 1 1258d 1237d 0/26 auto-closed as invalid on 2020/12/25 16:54
upstream KCSAN: data-race in do_epoll_ctl / do_epoll_ctl (3) fs 1 628d 628d 0/26 auto-closed as invalid on 2022/09/16 09:55

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

read-write to 0xffffffff86f62b10 of 8 bytes by task 27075 on cpu 0:
 do_epoll_ctl+0x8be/0x920 fs/eventpoll.c:2258
 __do_sys_epoll_ctl fs/eventpoll.c:2284 [inline]
 __se_sys_epoll_ctl fs/eventpoll.c:2275 [inline]
 __x64_sys_epoll_ctl+0xc6/0xf0 fs/eventpoll.c:2275
 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 0xffffffff86f62b10 of 8 bytes by task 27077 on cpu 1:
 do_epoll_ctl+0x4ff/0x920 fs/eventpoll.c:2195
 __do_sys_epoll_ctl fs/eventpoll.c:2284 [inline]
 __se_sys_epoll_ctl fs/eventpoll.c:2275 [inline]
 __x64_sys_epoll_ctl+0xc6/0xf0 fs/eventpoll.c:2275
 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: 0x0000000000001055 -> 0x000000000000106c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 27077 Comm: syz-executor.3 Not tainted 6.4.0-rc6-syzkaller-00242-g1639fae5132b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/17 09:05 upstream 1639fae5132b f3921d4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in do_epoll_ctl / do_epoll_ctl
* Struck through repros no longer work on HEAD.