From ee01a14d9ddcf3f832f9ceb837888501cb496e27 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 17 Jun 2011 09:47:23 -0400
Subject: [PATCH] cifs: close sget() races
have ->s_fs_info set by the set() callback passed to sget()
Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/cifs/cifsfs.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 46960b7ee433..ba2b2da360d3 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -629,6 +629,13 @@ out:
return dparent;
}
+static int cifs_set_super(struct super_block *sb, void *data)
+{
+ struct cifs_mnt_data *mnt_data = data;
+ sb->s_fs_info = mnt_data->cifs_sb;
+ return set_anon_super(sb, NULL);
+}
+
static struct dentry *
cifs_do_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
@@ -678,14 +685,14 @@ cifs_do_mount(struct file_system_type *fs_type,
mnt_data.cifs_sb = cifs_sb;
mnt_data.flags = flags;
- sb = sget(fs_type, cifs_match_super, set_anon_super, &mnt_data);
+ sb = sget(fs_type, cifs_match_super, cifs_set_super, &mnt_data);
if (IS_ERR(sb)) {
root = ERR_CAST(sb);
cifs_umount(cifs_sb);
goto out;
}
- if (sb->s_fs_info) {
+ if (sb->s_root) {
cFYI(1, "Use existing superblock");
cifs_umount(cifs_sb);
goto out_shared;
@@ -694,7 +701,6 @@ cifs_do_mount(struct file_system_type *fs_type,
sb->s_flags = flags;
/* BB should we make this contingent on mount parm? */
sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
- sb->s_fs_info = cifs_sb;
rc = cifs_read_super(sb);
if (rc) {
--
GitLab