[PATCH 2/7] esp: Fix locking on page fragment allocation
flat view
STALE3340d
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: 2017-08-29 10:31:43
Subsystem:
networking [general], networking [ipsec], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Steffen Klassert, Herbert Xu, Linus Torvalds
We allocate the page fragment for the ESP trailer inside
a spinlock, but consume it outside of the lock. This
is racy as some other cou could get the same page fragment
then. Fix this by consuming the page fragment inside the
lock too.
Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
net/ipv4/esp4.c | 5 +++--
net/ipv6/esp6.c | 5 +++--
2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index dbb31a9..a8ddb95 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c@@ -292,8 +292,6 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * kunmap_atomic(vaddr); - spin_unlock_bh(&x->lock); - nfrags = skb_shinfo(skb)->nr_frags; __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
@@ -301,6 +299,9 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * skb_shinfo(skb)->nr_frags = ++nfrags; pfrag->offset = pfrag->offset + allocsize; + + spin_unlock_bh(&x->lock); + nfrags++; skb->len += tailen;
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 392def1..4e3fdc88 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c@@ -260,8 +260,6 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info kunmap_atomic(vaddr); - spin_unlock_bh(&x->lock); - nfrags = skb_shinfo(skb)->nr_frags; __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
@@ -269,6 +267,9 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info skb_shinfo(skb)->nr_frags = ++nfrags; pfrag->offset = pfrag->offset + allocsize; + + spin_unlock_bh(&x->lock); + nfrags++; skb->len += tailen;
--
2.7.4