diff options
author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2022-10-04 21:47:50 -0400 |
---|---|---|
committer | Stefan Schmidt <stefan@datenfreihafen.org> | 2022-10-05 12:37:10 +0200 |
commit | b12e924a2f5b960373459c8f8a514f887adf5cac (patch) | |
tree | a1b3f6f201d03b87caa5e6a276a1e1f84febdfb4 | |
parent | 2eb2756f6c9e9621e022d78321ce40a62c4520b5 (diff) |
net/ieee802154: don't warn zero-sized raw_sendmsg()
syzbot is hitting skb_assert_len() warning at __dev_queue_xmit() [1],
for PF_IEEE802154 socket's zero-sized raw_sendmsg() request is hitting
__dev_queue_xmit() with skb->len == 0.
Since PF_IEEE802154 socket's zero-sized raw_sendmsg() request was
able to return 0, don't call __dev_queue_xmit() if packet length is 0.
----------
#include <sys/socket.h>
#include <netinet/in.h>
int main(int argc, char *argv[])
{
struct sockaddr_in addr = { .sin_family = AF_INET, .sin_addr.s_addr = htonl(INADDR_LOOPBACK) };
struct iovec iov = { };
struct msghdr hdr = { .msg_name = &addr, .msg_namelen = sizeof(addr), .msg_iov = &iov, .msg_iovlen = 1 };
sendmsg(socket(PF_IEEE802154, SOCK_RAW, 0), &hdr, 0);
return 0;
}
----------
Note that this might be a sign that commit fd1894224407c484 ("bpf: Don't
redirect packets with invalid pkt_len") should be reverted, for
skb->len == 0 was acceptable for at least PF_IEEE802154 socket.
Link: https://syzkaller.appspot.com/bug?extid=5ea725c25d06fb9114c4 [1]
Reported-by: syzbot <syzbot+5ea725c25d06fb9114c4@syzkaller.appspotmail.com>
Fixes: fd1894224407c484 ("bpf: Don't redirect packets with invalid pkt_len")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20221005014750.3685555-2-aahringo@redhat.com
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
-rw-r--r-- | net/ieee802154/socket.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/ieee802154/socket.c b/net/ieee802154/socket.c index 7889e1ef7fad..6e55fae4c686 100644 --- a/net/ieee802154/socket.c +++ b/net/ieee802154/socket.c @@ -272,6 +272,10 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) err = -EMSGSIZE; goto out_dev; } + if (!size) { + err = 0; + goto out_dev; + } hlen = LL_RESERVED_SPACE(dev); tlen = dev->needed_tailroom; |