syzbot


KCSAN: data-race in inet_dgram_connect / udp_lib_get_port

Status: closed as invalid on 2019/11/19 13:44
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 1139d, last: 1139d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in inet_dgram_connect / udp_lib_get_port (2) 3 1107d 1112d 0/24 auto-closed as invalid on 2020/02/05 16:37
upstream KCSAN: data-race in inet_dgram_connect / udp_lib_get_port (3) 1 763d 727d 0/24 auto-closed as invalid on 2020/12/25 11:24
upstream KCSAN: data-race in inet_dgram_connect / udp_lib_get_port (4) 1 676d 676d 0/24 auto-closed as invalid on 2021/03/07 18:58
upstream KCSAN: data-race in inet_dgram_connect / udp_lib_get_port (5) 6 559d 546d 22/24 fixed on 2021/11/10 00:50

Sample crash report:
==================================================================
BUG: KCSAN: data-race in inet_dgram_connect / udp_lib_get_port

read to 0xffff8880aae6b6ce of 2 bytes by task 17811 on cpu 1:
 inet_dgram_connect+0x8e/0x1a0 net/ipv4/af_inet.c:569
 __sys_connect+0x1e9/0x250 net/socket.c:1828
 __do_sys_connect net/socket.c:1839 [inline]
 __se_sys_connect net/socket.c:1836 [inline]
 __x64_sys_connect+0x4c/0x60 net/socket.c:1836
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880aae6b6ce of 2 bytes by task 17810 on cpu 0:
 udp_lib_get_port+0x4ba/0xd40 net/ipv4/udp.c:304
 udp_v4_get_port+0xf9/0x120 net/ipv4/udp.c:350
 __inet_bind+0x380/0x6b0 net/ipv4/af_inet.c:524
 inet_bind+0xc6/0x110 net/ipv4/af_inet.c:453
 __sys_bind+0x1df/0x220 net/socket.c:1647
 __do_sys_bind net/socket.c:1658 [inline]
 __se_sys_bind net/socket.c:1656 [inline]
 __x64_sys_bind+0x4c/0x60 net/socket.c:1656
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17810 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 17810 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xf5/0x159 lib/dump_stack.c:113
 panic+0x210/0x640 kernel/panic.c:221
 kcsan_report.cold+0xc/0x10 kernel/kcsan/report.c:302
 __kcsan_setup_watchpoint+0x32e/0x4a0 kernel/kcsan/core.c:411
 __tsan_write2 kernel/kcsan/kcsan.c:34 [inline]
 __tsan_write2+0x32/0x40 kernel/kcsan/kcsan.c:34
 udp_lib_get_port+0x4ba/0xd40 net/ipv4/udp.c:304
 udp_v4_get_port+0xf9/0x120 net/ipv4/udp.c:350
 __inet_bind+0x380/0x6b0 net/ipv4/af_inet.c:524
 inet_bind+0xc6/0x110 net/ipv4/af_inet.c:453
 __sys_bind+0x1df/0x220 net/socket.c:1647
 __do_sys_bind net/socket.c:1658 [inline]
 __se_sys_bind net/socket.c:1656 [inline]
 __x64_sys_bind+0x4c/0x60 net/socket.c:1656
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x459f39
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2294990c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39
RDX: 0000000000000010 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f22949916d4
R13: 00000000004c0253 R14: 00000000004d2528 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2019/10/26 23:00 https://github.com/google/ktsan.git kcsan 05f2236801fe 25bb509e .config log report
* Struck through repros no longer work on HEAD.