diff options
| author | David Howells <dhowells@redhat.com> | 2023-06-14 09:04:16 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-06-16 11:45:16 -0700 |
| commit | 5a6f6873606e03a0a95afe40ba5e84bb6e28a26f (patch) | |
| tree | b1e2cbd90486c6d662a2c6c4f3546ec366122526 /net/ipv6/ip6_output.c | |
| parent | c08afcdcf95288c627267bb20002e8baaf3394e1 (diff) | |
ip, ip6: Fix splice to raw and ping sockets
Splicing to SOCK_RAW sockets may set MSG_SPLICE_PAGES, but in such a case,
__ip_append_data() will call skb_splice_from_iter() to access the 'from'
data, assuming it to point to a msghdr struct with an iter, instead of
using the provided getfrag function to access it.
In the case of raw_sendmsg(), however, this is not the case and 'from' will
point to a raw_frag_vec struct and raw_getfrag() will be the frag-getting
function. A similar issue may occur with rawv6_sendmsg().
Fix this by ignoring MSG_SPLICE_PAGES if getfrag != ip_generic_getfrag as
ip_generic_getfrag() expects "from" to be a msghdr*, but the other getfrags
don't. Note that this will prevent MSG_SPLICE_PAGES from being effective
for udplite.
This likely affects ping sockets too. udplite looks like it should be okay
as it expects "from" to be a msghdr.
Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000ae4cbf05fdeb8349@google.com/
Fixes: 2dc334f1a63a ("splice, net: Use sendmsg(MSG_SPLICE_PAGES) rather than ->sendpage()")
Tested-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com
cc: David Ahern <dsahern@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/1410156.1686729856@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv6/ip6_output.c')
| -rw-r--r-- | net/ipv6/ip6_output.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index c06ff7519f19..1e8c90e97608 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1593,7 +1593,8 @@ emsgsize: } else if ((flags & MSG_SPLICE_PAGES) && length) { if (inet_sk(sk)->hdrincl) return -EPERM; - if (rt->dst.dev->features & NETIF_F_SG) + if (rt->dst.dev->features & NETIF_F_SG && + getfrag == ip_generic_getfrag) /* We need an empty buffer to attach stuff to */ paged = true; else |