diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2026-06-25 09:05:08 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-06-29 17:29:15 -0700 |
| commit | 62b68b774f06bf52e329f254f0199bc43d350ccf (patch) | |
| tree | b5d0e8ce0962378b4bc4ca86c7fc8d2e1b5ea4c7 | |
| parent | 32f1c2bbb26ae2be476c8b66e3b41789b6b97bfc (diff) | |
| download | linux-next-62b68b774f06bf52e329f254f0199bc43d350ccf.tar.gz linux-next-62b68b774f06bf52e329f254f0199bc43d350ccf.zip | |
eth: fbnic: don't cache shinfo across skb realloc
fbnic_tx_lso() calls skb_cow_head() which may reallocate the skb
including the shared info. We can't use the pointer calculated
before the call.
BUG: KASAN: slab-use-after-free in fbnic_tx_lso.isra.0+0x668/0x8e0
Read of size 4 at addr ff110000262edd98 by task swapper/5/0
Call Trace:
fbnic_tx_lso.isra.0+0x668/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
Allocated by task 8653:
__alloc_skb+0x11e/0x5f0
alloc_skb_with_frags+0xcc/0x6c0
sock_alloc_send_pskb+0x327/0x3f0
__ip_append_data+0x188b/0x47a0
ip_make_skb+0x24a/0x300
udp_sendmsg+0x14d2/0x21e0
Freed by task 0:
kfree+0x123/0x5a0
pskb_expand_head+0x36c/0xfa0
fbnic_tx_lso.isra.0+0x500/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
sch_direct_xmit+0x25b/0x1100
The buggy address belongs to the object at ff110000262edc40
which belongs to the cache skbuff_small_head of size 640
The buggy address is located 344 bytes inside of
freed 640-byte region [ff110000262edc40, ff110000262ede
Link: https://netdev.bots.linux.dev/logs/vmksft/fbnic-qemu-dbg/results/705762/15-uso-py/stderr
Fixes: b0b0f52042ac ("eth: fbnic: support TCP segmentation offload")
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://patch.msgid.link/20260625160508.3327986-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/ethernet/meta/fbnic/fbnic_txrx.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c index 9cd85a0d0c3a..401f8b8ae1ca 100644 --- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c +++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c @@ -194,16 +194,18 @@ static bool fbnic_tx_tstamp(struct sk_buff *skb) static bool fbnic_tx_lso(struct fbnic_ring *ring, struct sk_buff *skb, - struct skb_shared_info *shinfo, __le64 *meta, - unsigned int *l2len, unsigned int *i3len) + __le64 *meta, unsigned int *l2len, unsigned int *i3len) { unsigned int l3_type, l4_type, l4len, hdrlen; + struct skb_shared_info *shinfo; unsigned char *l4hdr; __be16 payload_len; if (unlikely(skb_cow_head(skb, 0))) return true; + shinfo = skb_shinfo(skb); + if (shinfo->gso_type & SKB_GSO_PARTIAL) { l3_type = FBNIC_TWD_L3_TYPE_OTHER; } else if (!skb->encapsulation) { @@ -258,7 +260,6 @@ fbnic_tx_lso(struct fbnic_ring *ring, struct sk_buff *skb, static bool fbnic_tx_offloads(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) { - struct skb_shared_info *shinfo = skb_shinfo(skb); unsigned int l2len, i3len; if (fbnic_tx_tstamp(skb)) @@ -273,8 +274,8 @@ fbnic_tx_offloads(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) *meta |= cpu_to_le64(FIELD_PREP(FBNIC_TWD_CSUM_OFFSET_MASK, skb->csum_offset / 2)); - if (shinfo->gso_size) { - if (fbnic_tx_lso(ring, skb, shinfo, meta, &l2len, &i3len)) + if (skb_is_gso(skb)) { + if (fbnic_tx_lso(ring, skb, meta, &l2len, &i3len)) return true; } else { *meta |= cpu_to_le64(FBNIC_TWD_FLAG_REQ_CSO); |