From 4afa5f9617927453ac04b24b584f6c718dfb4f45 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Sun, 1 Nov 2015 17:11:19 +0800 Subject: [PATCH] crypto: algif_hash - Only export and import on sockets with data The hash_accept call fails to work on sockets that have not received any data. For some algorithm implementations it may cause crashes. This patch fixes this by ensuring that we only export and import on sockets that have received data. Cc: stable@vger.kernel.org Reported-by: Harsh Jain Signed-off-by: Herbert Xu Tested-by: Stephan Mueller --- crypto/algif_hash.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c index 1396ad0787fc..b4c24fe3dcfb 100644 --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -181,9 +181,14 @@ static int hash_accept(struct socket *sock, struct socket *newsock, int flags) struct sock *sk2; struct alg_sock *ask2; struct hash_ctx *ctx2; + bool more; int err; - err = crypto_ahash_export(req, state); + lock_sock(sk); + more = ctx->more; + err = more ? crypto_ahash_export(req, state) : 0; + release_sock(sk); + if (err) return err; @@ -194,7 +199,10 @@ static int hash_accept(struct socket *sock, struct socket *newsock, int flags) sk2 = newsock->sk; ask2 = alg_sk(sk2); ctx2 = ask2->private; - ctx2->more = 1; + ctx2->more = more; + + if (!more) + return err; err = crypto_ahash_import(&ctx2->req, state); if (err) {