KCSAN: data-race in packet_do_bind / packet

KCSAN: data-race in packet_do_bind / packet_getname (4)
Status: auto-closed as invalid on 2021/03/06 13:33
Reported-by: syzbot+a7e88feac4411e409be4@syzkaller.appspotmail.com
First crash: 267d, last: 186d

similar bugs (4):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in packet_do_bind / packet_getname	16	551d	649d	0/22	auto-closed as invalid on 2020/04/11 02:48
upstream	KCSAN: data-race in packet_do_bind / packet_getname (5)	4	51d	50d	21/22	internal: reported on 2021/06/15 14:39
upstream	KCSAN: data-race in packet_do_bind / packet_getname (3)	8	335d	372d	0/22	auto-closed as invalid on 2020/10/09 06:50
upstream	KCSAN: data-race in packet_do_bind / packet_getname (2)	2	444d	466d	0/22	closed as invalid on 2020/06/18 14:24

Sample crash report:

==================================================================
BUG: KCSAN: data-race in packet_do_bind / packet_getname

write to 0xffff88810e580cd4 of 4 bytes by task 13566 on cpu 0:
 packet_do_bind+0x3d9/0x700 net/packet/af_packet.c:3182
 packet_bind+0xc3/0xd0 net/packet/af_packet.c:3246
 __sys_bind+0x200/0x290 net/socket.c:1635
 __do_sys_bind net/socket.c:1646 [inline]
 __se_sys_bind net/socket.c:1644 [inline]
 __x64_sys_bind+0x3d/0x50 net/socket.c:1644
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88810e580cd4 of 4 bytes by task 13594 on cpu 1:
 packet_getname+0xba/0x1a0 net/packet/af_packet.c:3520
 __sys_getsockname+0x10e/0x1a0 net/socket.c:1885
 __do_sys_getsockname net/socket.c:1900 [inline]
 __se_sys_getsockname net/socket.c:1897 [inline]
 __x64_sys_getsockname+0x3e/0x50 net/socket.c:1897
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13594 Comm: syz-executor.5 Not tainted 5.11.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 13594 Comm: syz-executor.5 Not tainted 5.11.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x116/0x15d lib/dump_stack.c:120
 panic+0x1e7/0x5fa kernel/panic.c:231
 kcsan_report+0x67b/0x680 kernel/kcsan/report.c:634
 kcsan_setup_watchpoint+0x472/0x4d0 kernel/kcsan/core.c:568
 packet_getname+0xba/0x1a0 net/packet/af_packet.c:3520
 __sys_getsockname+0x10e/0x1a0 net/socket.c:1885
 __do_sys_getsockname net/socket.c:1900 [inline]
 __se_sys_getsockname net/socket.c:1897 [inline]
 __x64_sys_getsockname+0x3e/0x50 net/socket.c:1897
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b09
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4990e35188 EFLAGS: 00000246 ORIG_RAX: 0000000000000033
RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000465b09
RDX: 0000000020000340 RSI: 00000000200003c0 RDI: 000000000000000a
RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200
R13: 00007fff303fda9f R14: 00007f4990e35300 R15: 0000000000022000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (5):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/01/30 13:32	upstream	0e9bcda5d286	fc9fd31e	.config	log	report	info	KCSAN: data-race in packet_do_bind / packet_getname
ci2-upstream-kcsan-gce	2021/01/17 05:47	upstream	54c6247d06f1	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/07 05:18	upstream	71c061d24438	c104d4a3	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/21 07:24	upstream	6a447b0e3151	04201c06	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/10 16:23	upstream	407ab579637c	cca87986	.config	log	report	info