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| author | Doron Roberts-Kedes | 2018-07-25 23:48:21 +0200 |
|---|---|---|
| committer | David S. Miller | 2018-07-26 23:11:34 +0200 |
| commit | 0a26cf3ff47d9e70fbed2fa79b0678ee70e25113 (patch) | |
| tree | 2074e891ca6150854be948a07a4aa60d13ab3069 /net/tls | |
| parent | net: sched: cls_api: fix dead code in switch (diff) | |
| download | kernel-qcow2-linux-0a26cf3ff47d9e70fbed2fa79b0678ee70e25113.tar.gz kernel-qcow2-linux-0a26cf3ff47d9e70fbed2fa79b0678ee70e25113.tar.xz kernel-qcow2-linux-0a26cf3ff47d9e70fbed2fa79b0678ee70e25113.zip | |
tls: Skip zerocopy path for ITER_KVEC
The zerocopy path ultimately calls iov_iter_get_pages, which defines the
step function for ITER_KVECs as simply, return -EFAULT. Taking the
non-zerocopy path for ITER_KVECs avoids the unnecessary fallback.
See https://lore.kernel.org/lkml/20150401023311.GL29656@ZenIV.linux.org.uk/T/#u
for a discussion of why zerocopy for vmalloc data is not a good idea.
Discovered while testing NBD traffic encrypted with ktls.
Fixes: c46234ebb4d1 ("tls: RX path for ktls")
Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/tls')
| -rw-r--r-- | net/tls/tls_sw.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 0687a7a4689f..f9971717f7e0 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -362,6 +362,7 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) int record_room; bool full_record; int orig_size; + bool is_kvec = msg->msg_iter.type & ITER_KVEC; if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) return -ENOTSUPP; @@ -410,8 +411,7 @@ alloc_encrypted: try_to_copy -= required_size - ctx->sg_encrypted_size; full_record = true; } - - if (full_record || eor) { + if (!is_kvec && (full_record || eor)) { ret = zerocopy_from_iter(sk, &msg->msg_iter, try_to_copy, &ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size, @@ -779,6 +779,7 @@ int tls_sw_recvmsg(struct sock *sk, bool cmsg = false; int target, err = 0; long timeo; + bool is_kvec = msg->msg_iter.type & ITER_KVEC; flags |= nonblock; @@ -822,7 +823,7 @@ int tls_sw_recvmsg(struct sock *sk, page_count = iov_iter_npages(&msg->msg_iter, MAX_SKB_FRAGS); to_copy = rxm->full_len - tls_ctx->rx.overhead_size; - if (to_copy <= len && page_count < MAX_SKB_FRAGS && + if (!is_kvec && to_copy <= len && page_count < MAX_SKB_FRAGS && likely(!(flags & MSG_PEEK))) { struct scatterlist sgin[MAX_SKB_FRAGS + 1]; int pages = 0; |