diff options
author | Sabrina Dubroca <sd@queasysnail.net> | 2024-02-06 17:18:22 -0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2024-02-10 21:38:19 +0000 |
commit | 32b55c5ff9103b8508c1e04bfa5a08c64e7a925f (patch) | |
tree | f15862fc76572e54089b2da8572cb5fc75a40375 | |
parent | 8590541473188741055d27b955db0777569438e3 (diff) |
net: tls: fix use-after-free with partial reads and async decrypt
tls_decrypt_sg doesn't take a reference on the pages from clear_skb,
so the put_page() in tls_decrypt_done releases them, and we trigger
a use-after-free in process_rx_list when we try to read from the
partially-read skb.
Fixes: fd31f3996af2 ("tls: rx: decrypt into a fresh skb")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/tls/tls_sw.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 63bef5666e36..a6eff21ade23 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -63,6 +63,7 @@ struct tls_decrypt_ctx { u8 iv[TLS_MAX_IV_SIZE]; u8 aad[TLS_MAX_AAD_SIZE]; u8 tail; + bool free_sgout; struct scatterlist sg[]; }; @@ -187,7 +188,6 @@ static void tls_decrypt_done(void *data, int err) struct aead_request *aead_req = data; struct crypto_aead *aead = crypto_aead_reqtfm(aead_req); struct scatterlist *sgout = aead_req->dst; - struct scatterlist *sgin = aead_req->src; struct tls_sw_context_rx *ctx; struct tls_decrypt_ctx *dctx; struct tls_context *tls_ctx; @@ -224,7 +224,7 @@ static void tls_decrypt_done(void *data, int err) } /* Free the destination pages if skb was not decrypted inplace */ - if (sgout != sgin) { + if (dctx->free_sgout) { /* Skip the first S/G entry as it points to AAD */ for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) { if (!sg) @@ -1583,6 +1583,7 @@ static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov, } else if (out_sg) { memcpy(sgout, out_sg, n_sgout * sizeof(*sgout)); } + dctx->free_sgout = !!pages; /* Prepare and submit AEAD request */ err = tls_do_decryption(sk, sgin, sgout, dctx->iv, |