mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-07-23 12:10:10 -04:00
Code Issues Packages Projects Releases Wiki Activity

eth: fbnic: don't cache shinfo across skb realloc

Browse Source 
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: b0b0f52042 ("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>
This commit is contained in:
Jakub Kicinski
2026-06-25 09:05:08 -07:00
parent 32f1c2bbb2
commit 62b68b774f
1 changed files with 6 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
View File

@@ -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);