[PATCH 3.12 198/235] Fix memory leaks in cifs_do_mount()

From: Jiri Slaby
Date: Fri Jan 27 2017 - 06:31:09 EST


From: Sachin Prabhu <sprabhu@xxxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 4214ebf4654798309364d0c678b799e402f38288 upstream.

Fix memory leaks introduced by the patch
Fs/cifs: make share unaccessible at root level mountable

Also move allocation of cifs_sb->prepath to cifs_setup_cifs_sb().

Signed-off-by: Sachin Prabhu <sprabhu@xxxxxxxxxx>
Tested-by: Aurelien Aptel <aaptel@xxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Acked-by: Aurelien Aptel <aaptel@xxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
fs/cifs/cifsfs.c | 20 ++++++++------------
fs/cifs/cifsproto.h | 2 +-
fs/cifs/connect.c | 11 ++++++++++-
3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 259f95121151..846b9916fdcd 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -665,26 +665,22 @@ cifs_do_mount(struct file_system_type *fs_type,
cifs_sb->mountdata = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
if (cifs_sb->mountdata == NULL) {
root = ERR_PTR(-ENOMEM);
- goto out_cifs_sb;
+ goto out_free;
}

- if (volume_info->prepath) {
- cifs_sb->prepath = kstrdup(volume_info->prepath, GFP_KERNEL);
- if (cifs_sb->prepath == NULL) {
- root = ERR_PTR(-ENOMEM);
- goto out_cifs_sb;
- }
+ rc = cifs_setup_cifs_sb(volume_info, cifs_sb);
+ if (rc) {
+ root = ERR_PTR(rc);
+ goto out_free;
}

- cifs_setup_cifs_sb(volume_info, cifs_sb);
-
rc = cifs_mount(cifs_sb, volume_info);
if (rc) {
if (!(flags & MS_SILENT))
cifs_dbg(VFS, "cifs_mount failed w/return code = %d\n",
rc);
root = ERR_PTR(rc);
- goto out_mountdata;
+ goto out_free;
}

mnt_data.vol = volume_info;
@@ -731,9 +727,9 @@ out:
cifs_cleanup_volume_info(volume_info);
return root;

-out_mountdata:
+out_free:
+ kfree(cifs_sb->prepath);
kfree(cifs_sb->mountdata);
-out_cifs_sb:
kfree(cifs_sb);
out_nls:
unload_nls(volume_info->local_nls);
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 6421d8b433b1..44d825cdf85e 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -179,7 +179,7 @@ extern int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
extern int cifs_readv_from_socket(struct TCP_Server_Info *server,
struct kvec *iov_orig, unsigned int nr_segs,
unsigned int to_read);
-extern void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
+extern int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
struct cifs_sb_info *cifs_sb);
extern int cifs_match_super(struct super_block *, void *);
extern void cifs_cleanup_volume_info(struct smb_vol *pvolume_info);
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index e4a36223d815..98c9c867f1b3 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3185,7 +3185,7 @@ void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
}
}

-void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
+int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
struct cifs_sb_info *cifs_sb)
{
INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
@@ -3267,6 +3267,15 @@ void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,

if ((pvolume_info->cifs_acl) && (pvolume_info->dynperm))
cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
+
+
+ if (pvolume_info->prepath) {
+ cifs_sb->prepath = kstrdup(pvolume_info->prepath, GFP_KERNEL);
+ if (cifs_sb->prepath == NULL)
+ return -ENOMEM;
+ }
+
+ return 0;
}

static void
--
2.11.0