| Message ID | 20141202150750.32521.20584.stgit@tstruk-mobl1 (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Herbert Xu |
| Headers | show |
On Tue, Dec 02, 2014 at 07:07:50AM -0800, Tadeusz Struk wrote: > Hi, > algif_skcipher sends 127 sgl buffers for encryption regardless of how > many buffers acctually have data to process, where the few first with > valid len and the rest with zero len. This is not very eficient and may cause > problems when algs do something like this without checking the buff > lenght: > for_each_sg(sgl, sg, sg_nents, i) > sg_virt(sg) > This patch marks the last one with data as the last one to process. > > Changes: > v2 - use data len to find the last buffer instead of nents in RX list. > > Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> > --- > crypto/algif_skcipher.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c > index f2a88a7..cde507f 100644 > --- a/crypto/algif_skcipher.c > +++ b/crypto/algif_skcipher.c > @@ -414,6 +414,23 @@ unlock: > return err ?: size; > } > > +static int skcipher_get_nents_with_data(struct scatterlist *sg, int len) > +{ This is way too complicated. Why not just do it every time we add data and modify sgl->cur? Cheers,
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c index f2a88a7..cde507f 100644 --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -414,6 +414,23 @@ unlock: return err ?: size; } +static int skcipher_get_nents_with_data(struct scatterlist *sg, int len) +{ + int nents; + + for (nents = 0; sg; sg = sg_next(sg)) { + if (!sg) + return nents; + + len -= sg->length; + if (!(len > 0)) + return nents; + nents++; + } + + return 0; +} + static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, struct msghdr *msg, size_t ignored, int flags) { @@ -437,6 +454,8 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, char __user *from = iov->iov_base; while (seglen) { + int nents; + sgl = list_first_entry(&ctx->tsgl, struct skcipher_sg_list, list); sg = sgl->sg; @@ -464,6 +483,8 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, if (!used) goto free; + nents = skcipher_get_nents_with_data(sg, used); + sg_mark_end(&sg[nents]); ablkcipher_request_set_crypt(&ctx->req, sg, ctx->rsgl.sg, used, ctx->iv); @@ -473,6 +494,7 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, crypto_ablkcipher_encrypt(&ctx->req) : crypto_ablkcipher_decrypt(&ctx->req), &ctx->completion); + sg_unmark_end(&sg[nents]); free: af_alg_free_sg(&ctx->rsgl);
Hi, algif_skcipher sends 127 sgl buffers for encryption regardless of how many buffers acctually have data to process, where the few first with valid len and the rest with zero len. This is not very eficient and may cause problems when algs do something like this without checking the buff lenght: for_each_sg(sgl, sg, sg_nents, i) sg_virt(sg) This patch marks the last one with data as the last one to process. Changes: v2 - use data len to find the last buffer instead of nents in RX list. Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> --- crypto/algif_skcipher.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) -- 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