diff options
| author | Gaosheng Cui <cuigaosheng1@huawei.com> | 2022-10-25 21:33:57 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-11-10 18:15:39 +0100 |
| commit | 2de8eec8afb75792440b8900a01d52b8f6742fd1 (patch) | |
| tree | ec782d047dd32aff1c2130dc88f529b96f9593e8 | |
| parent | bd07f8067b35153190ad63e5174987e0a1335031 (diff) | |
capabilities: fix potential memleak on error path from vfs_getxattr_alloc()
commit 8cf0a1bc12870d148ae830a4ba88cfdf0e879cee upstream.
In cap_inode_getsecurity(), we will use vfs_getxattr_alloc() to
complete the memory allocation of tmpbuf, if we have completed
the memory allocation of tmpbuf, but failed to call handler->get(...),
there will be a memleak in below logic:
|-- ret = (int)vfs_getxattr_alloc(mnt_userns, ...)
| /* ^^^ alloc for tmpbuf */
|-- value = krealloc(*xattr_value, error + 1, flags)
| /* ^^^ alloc memory */
|-- error = handler->get(handler, ...)
| /* error! */
|-- *xattr_value = value
| /* xattr_value is &tmpbuf (memory leak!) */
So we will try to free(tmpbuf) after vfs_getxattr_alloc() fails to fix it.
Cc: stable@vger.kernel.org
Fixes: 8db6c34f1dbc ("Introduce v3 namespaced file capabilities")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
[PM: subject line and backtrace tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | security/commoncap.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/security/commoncap.c b/security/commoncap.c index 5fc8986c3c77c..bc751fa5adad7 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -401,8 +401,10 @@ int cap_inode_getsecurity(struct user_namespace *mnt_userns, &tmpbuf, size, GFP_NOFS); dput(dentry); - if (ret < 0 || !tmpbuf) - return ret; + if (ret < 0 || !tmpbuf) { + size = ret; + goto out_free; + } fs_ns = inode->i_sb->s_user_ns; cap = (struct vfs_cap_data *) tmpbuf; |