syzbot

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BUG: KCSAN: data-race in ns_capable / proc_cgroup_show

write to 0xffff88810885206c of 4 bytes by task 570 on cpu 1:
 ns_capable_common kernel/capability.c:377 [inline]
 ns_capable+0x86/0xb0 kernel/capability.c:396
 netlink_allowed net/netlink/af_netlink.c:923 [inline]
 netlink_sendmsg+0x3ba/0x7c0 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmsg+0x1ed/0x270 net/socket.c:2433
 __do_sys_sendmsg net/socket.c:2442 [inline]
 __se_sys_sendmsg net/socket.c:2440 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2440
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810885206c of 4 bytes by task 1019 on cpu 0:
 proc_cgroup_show+0x640/0x930 kernel/cgroup/cgroup.c:5823
 proc_single_show+0x84/0x100 fs/proc/base.c:774
 seq_read_iter+0x2ef/0x910 fs/seq_file.c:227
 seq_read+0x221/0x260 fs/seq_file.c:159
 vfs_read+0x154/0x5d0 fs/read_write.c:494
 ksys_read+0xce/0x180 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:642
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00404040 -> 0x00404140

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1019 Comm: systemd-journal Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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