syzbot


KCSAN: data-race in getrusage / zap_page_range_single

Status: moderation: reported on 2025/03/25 08:44
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+e47c1ad6a08dcb25ccd1@syzkaller.appspotmail.com
First crash: 31d, last: 26d

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

write to 0xffff88811992b278 of 8 bytes by task 7056 on cpu 0:
 update_hiwater_rss include/linux/mm.h:2660 [inline]
 zap_page_range_single+0x1a2/0x2f0 mm/memory.c:2022
 unmap_mapping_range_vma mm/memory.c:3846 [inline]
 unmap_mapping_range_tree mm/memory.c:3863 [inline]
 unmap_mapping_pages mm/memory.c:3929 [inline]
 unmap_mapping_range+0x16d/0x1b0 mm/memory.c:3966
 shmem_fallocate+0x28b/0x890 mm/shmem.c:3695
 vfs_fallocate+0x368/0x3b0 fs/open.c:338
 madvise_remove mm/madvise.c:1034 [inline]
 madvise_vma_behavior mm/madvise.c:1269 [inline]
 madvise_walk_vmas mm/madvise.c:1511 [inline]
 do_madvise+0x14cc/0x2a60 mm/madvise.c:1698
 __do_sys_madvise mm/madvise.c:1714 [inline]
 __se_sys_madvise mm/madvise.c:1712 [inline]
 __x64_sys_madvise+0x61/0x70 mm/madvise.c:1712
 x64_sys_call+0x23b8/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:29
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811992b278 of 8 bytes by task 7047 on cpu 1:
 get_mm_hiwater_rss include/linux/mm.h:2647 [inline]
 setmax_mm_hiwater_rss include/linux/mm.h:2677 [inline]
 getrusage+0xa17/0xb70 kernel/sys.c:1876
 io_sq_thread+0x5e0/0x1140 io_uring/sqpoll.c:310
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000000016f7 -> 0x0000000000002217

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7047 Comm: iou-sqp-7046 Not tainted 6.14.0-syzkaller-10514-g7f2ff7b62617 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/30 08:10 upstream 7f2ff7b62617 d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in getrusage / zap_page_range_single
2025/03/25 08:44 upstream 3ba7dfb8da62 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in getrusage / zap_page_range_single
2025/03/25 08:43 upstream 3ba7dfb8da62 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in getrusage / zap_page_range_single
* Struck through repros no longer work on HEAD.