syzbot


KCSAN: data-race in _copy_from_iter / _copy_to_iter

Status: auto-obsoleted due to no activity on 2023/12/26 01:45
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+ed284c457f2f9b839aac@syzkaller.appspotmail.com
First crash: 436d, last: 434d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in _copy_from_iter / _copy_to_iter (2) mm 2 387d 392d 0/28 auto-obsoleted due to no activity on 2024/02/11 02:25

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

read to 0xffff88814ee06000 of 4096 bytes by task 16629 on cpu 0:
 instrument_copy_to_user include/linux/instrumented.h:113 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_iovec include/linux/iov_iter.h:51 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x2aa/0xb20 lib/iov_iter.c:186
 copy_page_to_iter+0x171/0x2b0 lib/iov_iter.c:381
 process_vm_rw_pages mm/process_vm_access.c:45 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:117 [inline]
 process_vm_rw_core mm/process_vm_access.c:215 [inline]
 process_vm_rw+0x5ed/0x8c0 mm/process_vm_access.c:283
 __do_sys_process_vm_readv mm/process_vm_access.c:295 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:291 [inline]
 __x64_sys_process_vm_readv+0x7a/0x90 mm/process_vm_access.c:291
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

write to 0xffff88814ee06000 of 4096 bytes by task 16612 on cpu 1:
 instrument_copy_from_user_before include/linux/instrumented.h:130 [inline]
 copy_from_user_iter lib/iov_iter.c:54 [inline]
 iterate_iovec include/linux/iov_iter.h:51 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:268 [inline]
 _copy_from_iter+0x2e7/0xb60 lib/iov_iter.c:279
 copy_page_from_iter+0x14f/0x280 lib/iov_iter.c:441
 process_vm_rw_pages mm/process_vm_access.c:43 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:117 [inline]
 process_vm_rw_core mm/process_vm_access.c:215 [inline]
 process_vm_rw+0x5d3/0x8c0 mm/process_vm_access.c:283
 __do_sys_process_vm_writev mm/process_vm_access.c:303 [inline]
 __se_sys_process_vm_writev mm/process_vm_access.c:298 [inline]
 __x64_sys_process_vm_writev+0x7a/0x90 mm/process_vm_access.c:298
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16612 Comm: syz-executor.2 Not tainted 6.7.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/21 01:44 upstream 98b1cc82c4af cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_from_iter / _copy_to_iter
2023/11/18 05:50 upstream 791c8ab095f7 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_from_iter / _copy_to_iter
* Struck through repros no longer work on HEAD.