Subject: [PATCH net 0/2] net: bridge: br_get_linkxstats_size() fixes

From: Eric Dumazet <[email-masked]>
Date: Mon, 4 Oct 2021 18:05:06 -0700

From: Eric Dumazet <[email-masked]>

This patch series attempts to fix the following syzbot report.

WARNING: CPU: 1 PID: 21425 at net/core/rtnetlink.c:5388 rtnl_stats_get+0x80f/0x8c0 net/core/rtnetlink.c:5388
Modules linked in:
CPU: 1 PID: 21425 Comm: syz-executor394 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rtnl_stats_get+0x80f/0x8c0 net/core/rtnetlink.c:5388
Code: e9 9c fc ff ff 4c 89 e7 89 0c 24 e8 ab 8b a8 fa 8b 0c 24 e9 bc fc ff ff 4c 89 e7 e8 9b 8b a8 fa e9 df fe ff ff e8 61 85 63 fa <0f> 0b e9 f7 fc ff ff 41 be ea ff ff ff e9 f9 fc ff ff 41 be 97 ff
RSP: 0018:ffffc9000cf77688 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 000000000000012c RCX: 0000000000000000
RDX: ffff8880211754c0 RSI: ffffffff8711571f RDI: 0000000000000003
RBP: ffff8880175aa780 R08: 00000000ffffffa6 R09: ffff88823bd5c04f
R10: ffffffff87115413 R11: 0000000000000001 R12: ffff8880175aab74
R13: ffff8880175aab40 R14: 00000000ffffffa6 R15: 0000000000000006
FS:  0000000001ff9300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000005cfd58 CR3: 000000002cd43000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5562
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:674
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4440d9

Eric Dumazet (2):
  net: bridge: use nla_total_size_64bit() in br_get_linkxstats_size()
  net: bridge: fix under estimation in br_get_linkxstats_size()

 net/bridge/br_netlink.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

-- 
2.33.0.800.g4c38ced690-goog