mirror of https://gitee.com/openkylin/linux.git
net: convert sk_buff_fclones.fclone_ref from atomic_t to refcount_t
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
633547973f
commit
2638595afc
|
@ -915,7 +915,7 @@ struct sk_buff_fclones {
|
||||||
|
|
||||||
struct sk_buff skb2;
|
struct sk_buff skb2;
|
||||||
|
|
||||||
atomic_t fclone_ref;
|
refcount_t fclone_ref;
|
||||||
};
|
};
|
||||||
|
|
||||||
/**
|
/**
|
||||||
|
@ -935,7 +935,7 @@ static inline bool skb_fclone_busy(const struct sock *sk,
|
||||||
fclones = container_of(skb, struct sk_buff_fclones, skb1);
|
fclones = container_of(skb, struct sk_buff_fclones, skb1);
|
||||||
|
|
||||||
return skb->fclone == SKB_FCLONE_ORIG &&
|
return skb->fclone == SKB_FCLONE_ORIG &&
|
||||||
atomic_read(&fclones->fclone_ref) > 1 &&
|
refcount_read(&fclones->fclone_ref) > 1 &&
|
||||||
fclones->skb2.sk == sk;
|
fclones->skb2.sk == sk;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
|
@ -268,7 +268,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
|
||||||
|
|
||||||
kmemcheck_annotate_bitfield(&fclones->skb2, flags1);
|
kmemcheck_annotate_bitfield(&fclones->skb2, flags1);
|
||||||
skb->fclone = SKB_FCLONE_ORIG;
|
skb->fclone = SKB_FCLONE_ORIG;
|
||||||
atomic_set(&fclones->fclone_ref, 1);
|
refcount_set(&fclones->fclone_ref, 1);
|
||||||
|
|
||||||
fclones->skb2.fclone = SKB_FCLONE_CLONE;
|
fclones->skb2.fclone = SKB_FCLONE_CLONE;
|
||||||
}
|
}
|
||||||
|
@ -629,7 +629,7 @@ static void kfree_skbmem(struct sk_buff *skb)
|
||||||
* This test would have no chance to be true for the clone,
|
* This test would have no chance to be true for the clone,
|
||||||
* while here, branch prediction will be good.
|
* while here, branch prediction will be good.
|
||||||
*/
|
*/
|
||||||
if (atomic_read(&fclones->fclone_ref) == 1)
|
if (refcount_read(&fclones->fclone_ref) == 1)
|
||||||
goto fastpath;
|
goto fastpath;
|
||||||
break;
|
break;
|
||||||
|
|
||||||
|
@ -637,7 +637,7 @@ static void kfree_skbmem(struct sk_buff *skb)
|
||||||
fclones = container_of(skb, struct sk_buff_fclones, skb2);
|
fclones = container_of(skb, struct sk_buff_fclones, skb2);
|
||||||
break;
|
break;
|
||||||
}
|
}
|
||||||
if (!atomic_dec_and_test(&fclones->fclone_ref))
|
if (!refcount_dec_and_test(&fclones->fclone_ref))
|
||||||
return;
|
return;
|
||||||
fastpath:
|
fastpath:
|
||||||
kmem_cache_free(skbuff_fclone_cache, fclones);
|
kmem_cache_free(skbuff_fclone_cache, fclones);
|
||||||
|
@ -1027,9 +1027,9 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
|
||||||
return NULL;
|
return NULL;
|
||||||
|
|
||||||
if (skb->fclone == SKB_FCLONE_ORIG &&
|
if (skb->fclone == SKB_FCLONE_ORIG &&
|
||||||
atomic_read(&fclones->fclone_ref) == 1) {
|
refcount_read(&fclones->fclone_ref) == 1) {
|
||||||
n = &fclones->skb2;
|
n = &fclones->skb2;
|
||||||
atomic_set(&fclones->fclone_ref, 2);
|
refcount_set(&fclones->fclone_ref, 2);
|
||||||
} else {
|
} else {
|
||||||
if (skb_pfmemalloc(skb))
|
if (skb_pfmemalloc(skb))
|
||||||
gfp_mask |= __GFP_MEMALLOC;
|
gfp_mask |= __GFP_MEMALLOC;
|
||||||
|
|
Loading…
Reference in New Issue