| Message ID | 20141127143811.GA25283@gondor.apana.org.au (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Herbert Xu |
| Headers | show |
Am Donnerstag, 27. November 2014, 22:38:12 schrieb Herbert Xu: Hi Herbert, >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> > >diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c >index 3438996..f80e652 100644 >--- a/crypto/algif_skcipher.c >+++ b/crypto/algif_skcipher.c >@@ -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; > >Thanks, Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c index 3438996..f80e652 100644 --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -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;
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> Thanks,