From: Ronnie Sahlberg <lsahlber@redhat.com>
To: linux-cifs <linux-cifs@vger.kernel.org>
Cc: Steve French <smfrench@gmail.com>
Subject: [PATCH] cifs: fix use after free in cifs_smb3_do_mount()
Date: Wed, 16 Dec 2020 08:51:33 +1000 [thread overview]
Message-ID: <20201215225133.20378-1-lsahlber@redhat.com> (raw)
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
fs/cifs/cifsfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 4c385eeecc05..2c6e54fa6429 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -836,12 +836,14 @@ cifs_smb3_do_mount(struct file_system_type *fs_type,
if (IS_ERR(sb)) {
root = ERR_CAST(sb);
cifs_umount(cifs_sb);
+ cifs_sb = NULL;
goto out;
}
if (sb->s_root) {
cifs_dbg(FYI, "Use existing superblock\n");
cifs_umount(cifs_sb);
+ cifs_sb = NULL;
} else {
rc = cifs_read_super(sb);
if (rc) {
@@ -852,7 +854,7 @@ cifs_smb3_do_mount(struct file_system_type *fs_type,
sb->s_flags |= SB_ACTIVE;
}
- root = cifs_get_root(cifs_sb->ctx, sb);
+ root = cifs_get_root(cifs_sb ? cifs_sb->ctx : old_ctx, sb);
if (IS_ERR(root))
goto out_super;
--
2.13.6
next reply other threads:[~2020-12-15 22:53 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-15 22:51 Ronnie Sahlberg [this message]
2020-12-15 22:57 ` [PATCH] cifs: fix use after free in cifs_smb3_do_mount() Steve French
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