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KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (7)

Status: auto-obsoleted due to no activity on 2023/10/16 13:09
Subsystems: serial
[Documentation on labels]
First crash: 283d, last: 283d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (3) serial 1 652d 652d 0/27 auto-obsoleted due to no activity on 2022/10/12 09:32
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common serial 3 914d 957d 0/27 auto-closed as invalid on 2022/01/22 22:31
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (10) serial 2 42d 66d 0/27 auto-obsoleted due to no activity on 2024/06/13 09:39
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (4) serial 1 591d 591d 0/27 auto-obsoleted due to no activity on 2022/12/12 09:48
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (6) serial 2 320d 324d 0/27 auto-obsoleted due to no activity on 2023/09/09 12:48
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (9) serial 2 142d 143d 0/27 auto-obsoleted due to no activity on 2024/03/05 13:33
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (2) serial 1 768d 768d 0/27 auto-closed as invalid on 2022/06/18 01:09
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (8) serial 1 183d 183d 0/27 auto-obsoleted due to no activity on 2024/01/24 11:50
upstream KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common (5) serial 1 424d 424d 0/27 auto-obsoleted due to no activity on 2023/05/28 00:42

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

write to 0xffff888108ce19dc of 4 bytes by task 17881 on cpu 0:
 tty_set_flow_change drivers/tty/tty.h:54 [inline]
 n_tty_check_throttle drivers/tty/n_tty.c:254 [inline]
 n_tty_receive_buf_common+0xa6e/0xbc0 drivers/tty/n_tty.c:1753
 n_tty_receive_buf+0x30/0x40 drivers/tty/n_tty.c:1774
 tiocsti+0x171/0x1d0 drivers/tty/tty_io.c:2291
 tty_ioctl+0x415/0xbc0 drivers/tty/tty_io.c:2690
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 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

write to 0xffff888108ce19dc of 4 bytes by task 17879 on cpu 1:
 __tty_set_flow_change drivers/tty/tty.h:49 [inline]
 n_tty_check_unthrottle+0x1a8/0x1c0 drivers/tty/n_tty.c:292
 n_tty_read+0xe92/0x1180 drivers/tty/n_tty.c:2307
 iterate_tty_read drivers/tty/tty_io.c:858 [inline]
 tty_read+0x152/0x450 drivers/tty/tty_io.c:933
 do_iter_read+0x4ac/0x7c0 fs/read_write.c:795
 vfs_readv fs/read_write.c:915 [inline]
 do_readv+0x176/0x2b0 fs/read_write.c:952
 __do_sys_readv fs/read_write.c:1043 [inline]
 __se_sys_readv fs/read_write.c:1040 [inline]
 __x64_sys_readv+0x45/0x50 fs/read_write.c:1040
 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: 0x00000002 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 17879 Comm: syz-executor.2 Tainted: G        W          6.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/11 13:02 upstream 0bb80ecc33a8 59da8366 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common
* Struck through repros no longer work on HEAD.