diff options
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 704adad8f07f..eefc61e3d0e4 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2994,17 +2994,19 @@ void tcp_put_md5sig_pool(void) EXPORT_SYMBOL(tcp_put_md5sig_pool); int tcp_md5_hash_header(struct tcp_md5sig_pool *hp, - struct tcphdr *th) + const struct tcphdr *th) { struct scatterlist sg; + struct tcphdr hdr; int err; - __sum16 old_checksum = th->check; - th->check = 0; + /* We are not allowed to change tcphdr, make a local copy */ + memcpy(&hdr, th, sizeof(hdr)); + hdr.check = 0; + /* options aren't included in the hash */ - sg_init_one(&sg, th, sizeof(struct tcphdr)); - err = crypto_hash_update(&hp->md5_desc, &sg, sizeof(struct tcphdr)); - th->check = old_checksum; + sg_init_one(&sg, &hdr, sizeof(hdr)); + err = crypto_hash_update(&hp->md5_desc, &sg, sizeof(hdr)); return err; } EXPORT_SYMBOL(tcp_md5_hash_header); |