From: Jakub Kicinski <[email protected]>
[ Upstream commit 97e1caa517e22d62a283b876fb8aa5f4672c83dd ]
There is no guarantee the record starts before the skb frags.
If we don't check for this condition copy amount will get
negative, leading to reads and writes to random memory locations.
Familiar hilarity ensues.
Fixes: 4799ac81e52a ("tls: Add rx inline crypto offload")
Signed-off-by: Jakub Kicinski <[email protected]>
Reviewed-by: John Hurley <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
net/tls/tls_device.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -610,14 +610,16 @@ static int tls_device_reencrypt(struct s
else
err = 0;
- copy = min_t(int, skb_pagelen(skb) - offset,
- rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE);
+ if (skb_pagelen(skb) > offset) {
+ copy = min_t(int, skb_pagelen(skb) - offset,
+ rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE);
- if (skb->decrypted)
- skb_store_bits(skb, offset, buf, copy);
+ if (skb->decrypted)
+ skb_store_bits(skb, offset, buf, copy);
- offset += copy;
- buf += copy;
+ offset += copy;
+ buf += copy;
+ }
skb_walk_frags(skb, skb_iter) {
copy = min_t(int, skb_iter->len,
