diff options
author | Xin Long <lucien.xin@gmail.com> | 2019-03-31 16:50:10 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2019-04-01 01:45:57 +0200 |
commit | 2ac695d1d602ce00b12170242f58c3d3a8e36d04 (patch) | |
tree | 62a3530ea82a7391c5731c04bcb9c76dc15f386e /net/tipc | |
parent | tipc: check link name with right length in tipc_nl_compat_link_set (diff) | |
download | linux-2ac695d1d602ce00b12170242f58c3d3a8e36d04.tar.xz linux-2ac695d1d602ce00b12170242f58c3d3a8e36d04.zip |
tipc: handle the err returned from cmd header function
Syzbot found a crash:
BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
Call Trace:
tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
__tipc_nl_compat_dumpit+0x59e/0xda0 net/tipc/netlink_compat.c:215
tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:280
tipc_nl_compat_handle net/tipc/netlink_compat.c:1226 [inline]
tipc_nl_compat_recv+0x1b5f/0x2750 net/tipc/netlink_compat.c:1265
genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg net/socket.c:632 [inline]
Uninit was created at:
__alloc_skb+0x309/0xa20 net/core/skbuff.c:208
alloc_skb include/linux/skbuff.h:1012 [inline]
netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg net/socket.c:632 [inline]
It was supposed to be fixed on commit 974cb0e3e7c9 ("tipc: fix uninit-value
in tipc_nl_compat_name_table_dump") by checking TLV_GET_DATA_LEN(msg->req)
in cmd->header()/tipc_nl_compat_name_table_dump_header(), which is called
ahead of tipc_nl_compat_name_table_dump().
However, tipc_nl_compat_dumpit() doesn't handle the error returned from cmd
header function. It means even when the check added in that fix fails, it
won't stop calling tipc_nl_compat_name_table_dump(), and the issue will be
triggered again.
So this patch is to add the process for the err returned from cmd header
function in tipc_nl_compat_dumpit().
Reported-by: syzbot+3ce8520484b0d4e260a5@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/tipc')
-rw-r--r-- | net/tipc/netlink_compat.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/tipc/netlink_compat.c b/net/tipc/netlink_compat.c index 0bfd03d67fdd..340a6e7c43a7 100644 --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -267,8 +267,14 @@ static int tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, if (msg->rep_type) tipc_tlv_init(msg->rep, msg->rep_type); - if (cmd->header) - (*cmd->header)(msg); + if (cmd->header) { + err = (*cmd->header)(msg); + if (err) { + kfree_skb(msg->rep); + msg->rep = NULL; + return err; + } + } arg = nlmsg_new(0, GFP_KERNEL); if (!arg) { |