From: Stefan Metzmacher metze@samba.org
[ Upstream commit bedc8f76b3539ac4f952114b316bcc2251e808ce ]
So far we were just lucky because the uninitialized members of struct msghdr are not used by default on a SOCK_STREAM tcp socket.
But as new things like msg_ubuf and sg_from_iter where added recently, we should play on the safe side and avoid potention problems in future.
Signed-off-by: Stefan Metzmacher metze@samba.org Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (SUSE) pc@cjr.nz Reviewed-by: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cifs/connect.c | 11 +++-------- fs/cifs/transport.c | 6 +----- 2 files changed, 4 insertions(+), 13 deletions(-)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 6e7d5b9e84b8..d1c3086d7ddd 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -695,9 +695,6 @@ cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg) int length = 0; int total_read;
- smb_msg->msg_control = NULL; - smb_msg->msg_controllen = 0; - for (total_read = 0; msg_data_left(smb_msg); total_read += length) { try_to_freeze();
@@ -748,7 +745,7 @@ int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, unsigned int to_read) { - struct msghdr smb_msg; + struct msghdr smb_msg = {}; struct kvec iov = {.iov_base = buf, .iov_len = to_read}; iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
@@ -758,15 +755,13 @@ cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, ssize_t cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read) { - struct msghdr smb_msg; + struct msghdr smb_msg = {};
/* * iov_iter_discard already sets smb_msg.type and count and iov_offset * and cifs_readv_from_socket sets msg_control and msg_controllen * so little to initialize in struct msghdr */ - smb_msg.msg_name = NULL; - smb_msg.msg_namelen = 0; iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
return cifs_readv_from_socket(server, &smb_msg); @@ -776,7 +771,7 @@ int cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page, unsigned int page_offset, unsigned int to_read) { - struct msghdr smb_msg; + struct msghdr smb_msg = {}; struct bio_vec bv = { .bv_page = page, .bv_len = to_read, .bv_offset = page_offset}; iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read); diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 383ae8744c33..b137006f0fd2 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -209,10 +209,6 @@ smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
*sent = 0;
- smb_msg->msg_name = NULL; - smb_msg->msg_namelen = 0; - smb_msg->msg_control = NULL; - smb_msg->msg_controllen = 0; if (server->noblocksnd) smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; else @@ -324,7 +320,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, sigset_t mask, oldmask; size_t total_len = 0, sent, size; struct socket *ssocket = server->ssocket; - struct msghdr smb_msg; + struct msghdr smb_msg = {}; __be32 rfc1002_marker;
if (cifs_rdma_enabled(server)) {