3.16.52-rc1 review patch. If anyone has any objections, please let me know.
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From: Ronnie Sahlberg lsahlber@redhat.com
commit bf2afee14e07de16d3cafc67edbfc2a3cc65e4bc upstream.
In SMB2_open there are several paths where the SendReceive2 call will return an error before it sets rsp_iov.iov_base thus leaving iov_base uninitialized.
Thus we need to check rsp before we dereference it in the call to get_rfc1002_length().
A report of this issue was previously reported in http://www.spinics.net/lists/linux-cifs/msg12846.html
RH-bugzilla : 1476151
Version 2 : * Lets properly initialize rsp_iov before we use it.
Signed-off-by: Ronnie Sahlberg lsahlber@redhat.com Reviewed-by: Pavel Shilovsky pshilov@microsoft.com. Signed-off-by: Steve French smfrench@gmail.com Reported-by: Xiaoli Feng xifeng@redhat.com [bwh: Backported to 3.16: zero-initialise iov instead of rsp_iov] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1114,7 +1114,7 @@ SMB2_open(const unsigned int xid, struct struct TCP_Server_Info *server; struct cifs_tcon *tcon = oparms->tcon; struct cifs_ses *ses = tcon->ses; - struct kvec iov[4]; + struct kvec iov[4] = {{NULL, 0}}; int resp_buftype; int uni_path_len; __le16 *copy_path = NULL; @@ -1215,7 +1215,7 @@ SMB2_open(const unsigned int xid, struct
if (rc != 0) { cifs_stats_fail_inc(tcon, SMB2_CREATE_HE); - if (err_buf) + if (err_buf && rsp) *err_buf = kmemdup(rsp, get_rfc1002_length(rsp) + 4, GFP_KERNEL); goto creat_exit;