CVE-2023-53853

In the Linux kernel, the following vulnerability has been resolved:

netlink: annotate accesses to nlk->cb_running

Both netlinkrecvmsg() and netlinknativeseqshow() read nlk->cbrunning locklessly. Use READONCE() there.

Add corresponding WRITEONCE() to netlinkdump() and __netlinkdumpstart()

syzbot reported: BUG: KCSAN: data-race in _netlinkdumpstart / netlinkrecvmsg

write to 0xffff88813ea4db59 of 1 bytes by task 28219 on cpu 0: __netlinkdumpstart+0x3af/0x4d0 net/netlink/afnetlink.c:2399 netlinkdumpstart include/linux/netlink.h:308 [inline] rtnetlinkrcvmsg+0x70f/0x8c0 net/core/rtnetlink.c:6130 netlinkrcvskb+0x126/0x220 net/netlink/afnetlink.c:2577 rtnetlinkrcv+0x1c/0x20 net/core/rtnetlink.c:6192 netlinkunicastkernel net/netlink/afnetlink.c:1339 [inline] netlinkunicast+0x56f/0x640 net/netlink/afnetlink.c:1365 netlinksendmsg+0x665/0x770 net/netlink/afnetlink.c:1942 socksendmsgnosec net/socket.c:724 [inline] socksendmsg net/socket.c:747 [inline] sockwriteiter+0x1aa/0x230 net/socket.c:1138 callwriteiter include/linux/fs.h:1851 [inline] newsyncwrite fs/readwrite.c:491 [inline] vfswrite+0x463/0x760 fs/readwrite.c:584 ksyswrite+0xeb/0x1a0 fs/readwrite.c:637 __dosyswrite fs/read_write.c:649 [inline] __sesyswrite fs/read_write.c:646 [inline] _x64syswrite+0x42/0x50 fs/readwrite.c:646 dosyscallx64 arch/x86/entry/common.c:50 [inline] dosyscall64+0x41/0xc0 arch/x86/entry/common.c:80 entrySYSCALL64afterhwframe+0x63/0xcd

read to 0xffff88813ea4db59 of 1 bytes by task 28222 on cpu 1: netlinkrecvmsg+0x3b4/0x730 net/netlink/afnetlink.c:2022 sockrecvmsgnosec+0x4c/0x80 net/socket.c:1017 ____sys_recvmsg+0x2db/0x310 net/socket.c:2718 ___sysrecvmsg net/socket.c:2762 [inline] dorecvmmsg+0x2e5/0x710 net/socket.c:2856 __sys_recvmmsg net/socket.c:2935 [inline] __dosysrecvmmsg net/socket.c:2958 [inline] __sesysrecvmmsg net/socket.c:2951 [inline] __x64sysrecvmmsg+0xe2/0x160 net/socket.c:2951 dosyscallx64 arch/x86/entry/common.c:50 [inline] dosyscall64+0x41/0xc0 arch/x86/entry/common.c:80 entrySYSCALL64afterhwframe+0x63/0xcd

value changed: 0x00 -> 0x01