syzbot


KCSAN: data-race in hrtimer_interrupt / print_tickdevice (3)

Status: auto-closed as invalid on 2021/09/10 15:52
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 516d, last: 481d
similar bugs (6):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (6) 5 130d 154d 0/24 auto-closed as invalid on 2022/08/27 09:49
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (4) 14 266d 431d 0/24 auto-closed as invalid on 2022/04/13 14:16
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (2) 3 567d 571d 0/24 auto-closed as invalid on 2021/06/16 18:46
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (5) 2 203d 203d 0/24 auto-closed as invalid on 2022/06/15 02:31
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice (7) 1 74d 74d 0/24 auto-obsoleted due to no activity on 2022/10/22 07:07
upstream KCSAN: data-race in hrtimer_interrupt / print_tickdevice 1 683d 683d 0/24 auto-closed as invalid on 2021/02/20 21:54

Sample crash report:
loop3: detected capacity change from 0 to 264192
==================================================================
BUG: KCSAN: data-race in hrtimer_interrupt / print_tickdevice

write to 0xffff888237d16f18 of 8 bytes by interrupt on cpu 1:
 hrtimer_interrupt+0x95/0xaf0 kernel/time/hrtimer.c:1642
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x1c0 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x64/0x80 arch/x86/kernel/apic/apic.c:1100
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
 __sanitizer_cov_trace_switch+0xf6/0x100 kernel/kcov.c:321
 check_event_type_and_length sound/core/seq/seq_clientmgr.c:992 [inline]
 snd_seq_write+0x1fa/0x530 sound/core/seq/seq_clientmgr.c:1061
 vfs_write+0x1f3/0x770 fs/read_write.c:603
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237d16f18 of 8 bytes by task 7915 on cpu 0:
 print_tickdevice+0x158/0x370 kernel/time/timer_list.c:204
 timer_list_show+0x74/0x180 kernel/time/timer_list.c:296
 seq_read_iter+0x60b/0x930 fs/seq_file.c:272
 proc_reg_read_iter+0xfc/0x170 fs/proc/inode.c:300
 call_read_iter include/linux/fs.h:2108 [inline]
 generic_file_splice_read+0x22a/0x310 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000016edd68430 -> 0x7fffffffffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7915 Comm: syz-executor.3 Not tainted 5.14.0-rc4-syzkaller #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 2021/08/06 15:46 upstream 902e7f373fff 2f537099 .config log report info KCSAN: data-race in hrtimer_interrupt / print_tickdevice
ci2-upstream-kcsan-gce 2021/07/02 13:04 upstream 3dbdb38e2869 658ebc66 .config log report info KCSAN: data-race in hrtimer_interrupt / print_tickdevice
* Struck through repros no longer work on HEAD.