From 50440213e2ae2ad15c5eadb8c9fab53a28bf413b Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Wed, 13 Feb 2019 14:31:53 +0800 Subject: [PATCH] cifs: fix memory leak of an allocated cifs_ntsd structure mainline inclusion from mainline-5.0 commit 73aaf920cc72 category: bugfix bugzilla: 7230 CVE: NA ------------------------------------------------- The call to SMB2_queary_acl can allocate memory to pntsd and also return a failure via a call to SMB2_query_acl (and then query_info). This occurs when query_info allocates the structure and then in query_info the call to smb2_validate_and_copy_iov fails. Currently the failure just returns without kfree'ing pntsd hence causing a memory leak. Currently, *data is allocated if it's not already pointing to a buffer, so it needs to be kfree'd only if was allocated in query_info, so the fix adds an allocated flag to track this. Also set *dlen to zero on an error just to be safe since *data is kfree'd. Also set errno to -ENOMEM if the allocation of *data fails. conflict: fs/cifs/smb2pdu.c conflict with:c5a5f38f075c cifs: add a smb2_compound_op and change QUERY_INFO to use it Signed-off-by: Colin Ian King Signed-off-by: Steve French Reviewed-by: Dan Carpener Signed-off-by: ZhangXiaoxu Reviewed-by: Miao Xie Signed-off-by: Yang Yingliang --- fs/cifs/smb2pdu.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 8758537130d2..ecd5db27e023 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -2706,6 +2706,7 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon, int resp_buftype; struct cifs_ses *ses = tcon->ses; int flags = 0; + bool allocated = false; cifs_dbg(FYI, "Query Info\n"); @@ -2745,14 +2746,21 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon, "Error %d allocating memory for acl\n", rc); *dlen = 0; + rc = -ENOMEM; goto qinf_exit; } + allocated = true; } } rc = validate_and_copy_iov(le16_to_cpu(rsp->OutputBufferOffset), le32_to_cpu(rsp->OutputBufferLength), &rsp_iov, min_len, *data); + if (rc && allocated) { + kfree(*data); + *data = NULL; + *dlen = 0; + } qinf_exit: SMB2_query_info_free(&rqst); -- GitLab