diff mbox series

[net] tls: Correct length of scatterlist in tls_sw_sendpage

Message ID 20180119203013.GA66428@AM-iPhone.dhcp.thefacebook.com
State Accepted, archived
Delegated to: David Miller
Headers show
Series [net] tls: Correct length of scatterlist in tls_sw_sendpage | expand

Commit Message

Dave Watson Jan. 19, 2018, 8:30 p.m. UTC 
The scatterlist is reused by both sendmsg and sendfile.
If a sendmsg of smaller number of pages is followed by a sendfile
of larger number of pages, the scatterlist may be too short, resulting
in a crash in gcm_encrypt.

Add sg_unmark_end to make the list the correct length.

tls_sw_sendmsg already calls sg_unmark_end correctly when it allocates
memory in alloc_sg, or in zerocopy_from_iter.

Signed-off-by: Dave Watson <davejwatson@fb.com>
---
 net/tls/tls_sw.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

David Miller Jan. 22, 2018, 9:27 p.m. UTC | #1 
From: Dave Watson <davejwatson@fb.com>
Date: Fri, 19 Jan 2018 12:30:13 -0800

> The scatterlist is reused by both sendmsg and sendfile.
> If a sendmsg of smaller number of pages is followed by a sendfile
> of larger number of pages, the scatterlist may be too short, resulting
> in a crash in gcm_encrypt.
> 
> Add sg_unmark_end to make the list the correct length.
> 
> tls_sw_sendmsg already calls sg_unmark_end correctly when it allocates
> memory in alloc_sg, or in zerocopy_from_iter.
> 
> Signed-off-by: Dave Watson <davejwatson@fb.com>

Applied, thanks Dave.
diff mbox series

Patch

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 61f394d..0a9b72f 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -577,6 +577,8 @@  int tls_sw_sendpage(struct sock *sk, struct page *page,
 		get_page(page);
 		sg = ctx->sg_plaintext_data + ctx->sg_plaintext_num_elem;
 		sg_set_page(sg, page, copy, offset);
+		sg_unmark_end(sg);
+
 		ctx->sg_plaintext_num_elem++;
 
 		sk_mem_charge(sk, copy);