syzbot


KCSAN: data-race in smc_poll / smc_switch_to_fallback

Status: auto-obsoleted due to no activity on 2023/03/26 15:22
Subsystems: net s390
[Documentation on labels]
Reported-by: syzbot+3b3f756e24586e8619c9@syzkaller.appspotmail.com
First crash: 471d, last: 471d

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

write to 0xffff8881321b9d3d of 1 bytes by task 9321 on cpu 0:
 smc_switch_to_fallback+0x5f/0x730 net/smc/af_smc.c:872
 smc_sendmsg+0x191/0x380 net/smc/af_smc.c:2656
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0x38f/0x500 net/socket.c:2476
 ___sys_sendmsg net/socket.c:2530 [inline]
 __sys_sendmsg+0x19a/0x230 net/socket.c:2559
 __do_sys_sendmsg net/socket.c:2568 [inline]
 __se_sys_sendmsg net/socket.c:2566 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2566
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881321b9d3d of 1 bytes by task 9320 on cpu 1:
 smc_poll+0x41/0x4a0 net/smc/af_smc.c:2737
 sock_poll+0x23e/0x260 net/socket.c:1353
 vfs_poll include/linux/poll.h:88 [inline]
 do_pollfd fs/select.c:873 [inline]
 do_poll fs/select.c:921 [inline]
 do_sys_poll+0x6d5/0xca0 fs/select.c:1015
 __do_sys_ppoll fs/select.c:1121 [inline]
 __se_sys_ppoll+0x195/0x1d0 fs/select.c:1101
 __x64_sys_ppoll+0x63/0x70 fs/select.c:1101
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9320 Comm: syz-executor.4 Tainted: G        W          6.2.0-rc3-syzkaller-00008-g1fe4fd6f5cad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/09 11:58 upstream 1fe4fd6f5cad 1dac8c7a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in smc_poll / smc_switch_to_fallback
* Struck through repros no longer work on HEAD.