crypto: algif_skcipher - Fixed blocking recvmsg

As most (all?) users of algif_skcipher are single-threaded and
therefore always write before reading from an algif_skcipher
socket, they never block and exercise that code-path.

It turns out that code path doesn't even work because we never
reload ctx->used after waking up so we never even see the new
data and immediately return an error (and a loud WARN_ON).

This patch fixes this by always reloading ctx->used.

Reported-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Stephan Mueller <smueller@chronox.de>
This commit is contained in:
Herbert Xu 2014-11-27 22:38:12 +08:00
parent 421d82f5b3
commit 1e104f9a25

View File

@ -448,14 +448,13 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
while (!sg->length)
sg++;
used = ctx->used;
if (!used) {
if (!ctx->used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto unlock;
}
used = min_t(unsigned long, used, seglen);
used = min_t(unsigned long, ctx->used, seglen);
used = af_alg_make_sg(&ctx->rsgl, from, used, 1);
err = used;