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net: core: reject skb_copy(_expand) for fraglist GSO skbs

SKB_GSO_FRAGLIST skbs must not be linearized, otherwise they become
invalid. Return NULL if such an skb is passed to skb_copy or
skb_copy_expand, in order to prevent a crash on a potential later
call to skb_gso_segment.

Fixes: 3a1296a38d ("net: Support GRO/GSO fraglist chaining.")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Felix Fietkau 2024-04-27 20:24:19 +02:00 committed by David S. Miller
parent 59c878cbcd
commit d091e579b8

View File

@ -2123,11 +2123,17 @@ static inline int skb_alloc_rx_flag(const struct sk_buff *skb)
struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask) struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask)
{ {
int headerlen = skb_headroom(skb); struct sk_buff *n;
unsigned int size = skb_end_offset(skb) + skb->data_len; unsigned int size;
struct sk_buff *n = __alloc_skb(size, gfp_mask, int headerlen;
skb_alloc_rx_flag(skb), NUMA_NO_NODE);
if (WARN_ON_ONCE(skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST))
return NULL;
headerlen = skb_headroom(skb);
size = skb_end_offset(skb) + skb->data_len;
n = __alloc_skb(size, gfp_mask,
skb_alloc_rx_flag(skb), NUMA_NO_NODE);
if (!n) if (!n)
return NULL; return NULL;
@ -2455,12 +2461,17 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
/* /*
* Allocate the copy buffer * Allocate the copy buffer
*/ */
struct sk_buff *n = __alloc_skb(newheadroom + skb->len + newtailroom, int head_copy_len, head_copy_off;
struct sk_buff *n;
int oldheadroom;
if (WARN_ON_ONCE(skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST))
return NULL;
oldheadroom = skb_headroom(skb);
n = __alloc_skb(newheadroom + skb->len + newtailroom,
gfp_mask, skb_alloc_rx_flag(skb), gfp_mask, skb_alloc_rx_flag(skb),
NUMA_NO_NODE); NUMA_NO_NODE);
int oldheadroom = skb_headroom(skb);
int head_copy_len, head_copy_off;
if (!n) if (!n)
return NULL; return NULL;