From: Xin Long lucien.xin@gmail.com
stable inclusion from stable-5.10.56 commit 4951ffa3fac8892949a09b630191ff12f35f4b72 bugzilla: 176004 https://gitee.com/openeuler/kernel/issues/I4DYZ4
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 3cf4375a090473d240281a0d2b04a3a5aaeac34b ]
One skb's skb_shinfo frags are not writable, and they can be shared with other skbs' like by pskb_copy(). To write the frags may cause other skb's data crash.
So before doing en/decryption, skb_cow_data() should always be called for a cloned or nonlinear skb if req dst is using the same sg as req src. While at it, the likely branch can be removed, as it will be covered by skb_cow_data().
Note that esp_input() has the same issue, and I will fix it in another patch. tipc_aead_encrypt() doesn't have this issue, as it only processes linear data in the unlikely branch.
Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Reported-by: Shuang Li shuali@redhat.com Signed-off-by: Xin Long lucien.xin@gmail.com Acked-by: Jon Maloy jmaloy@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com --- net/tipc/crypto.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c index 2301b66280de..f8e73c4a0093 100644 --- a/net/tipc/crypto.c +++ b/net/tipc/crypto.c @@ -891,16 +891,10 @@ static int tipc_aead_decrypt(struct net *net, struct tipc_aead *aead, if (unlikely(!aead)) return -ENOKEY;
- /* Cow skb data if needed */ - if (likely(!skb_cloned(skb) && - (!skb_is_nonlinear(skb) || !skb_has_frag_list(skb)))) { - nsg = 1 + skb_shinfo(skb)->nr_frags; - } else { - nsg = skb_cow_data(skb, 0, &unused); - if (unlikely(nsg < 0)) { - pr_err("RX: skb_cow_data() returned %d\n", nsg); - return nsg; - } + nsg = skb_cow_data(skb, 0, &unused); + if (unlikely(nsg < 0)) { + pr_err("RX: skb_cow_data() returned %d\n", nsg); + return nsg; }
/* Allocate memory for the AEAD operation */