mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-16 09:02:21 -04:00
Code Issues Packages Projects Releases Wiki Activity

xsk: avoid skb leak in XDP_TX_METADATA case

Browse Source 
Fix it by explicitly adding kfree_skb() before returning back to its
caller.

How to reproduce it in virtio_net:
1. the current skb is the first one (which means no frag and xs->skb is
   NULL) and users enable metadata feature.
2. xsk_skb_metadata() returns a error code.
3. the caller xsk_build_skb() clears skb by using 'skb = NULL;'.
4. there is no chance to free this skb anymore.

Closes: https://lore.kernel.org/all/20260415085204.3F87AC19424@smtp.kernel.org/
Fixes: 30c3055f9c ("xsk: wrap generic metadata handling onto separate function")
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20260502200722.53960-7-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jason Xing
2026-05-02 23:07:20 +03:00
committed by Jakub Kicinski
parent 3dec153ae4
commit 8c2cff50af
1 changed files with 3 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
net/xdp/xsk.c
View File

@@ -821,8 +821,10 @@ static struct sk_buff *xsk_build_skb_zerocopy(struct xdp_sock *xs,
skb_reserve(skb, hr);
if (desc->options & XDP_TX_METADATA) {
err = xsk_skb_metadata(skb, buffer, desc, pool, hr);
if (unlikely(err))
if (unlikely(err)) {
kfree_skb(skb);
return ERR_PTR(err);
}
}
} else {
struct xsk_addrs *xsk_addr;