getname_kernel() needs to make sure that ->name != ->iname in long case

[ Upstream commit 30ce4d1903e1d8a7ccd110860a5eef3c638ed8be ]

missed it in "kill struct filename.separate" several years ago.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>

diff --git a/fs/namei.c b/fs/namei.c
index 0d97235019a9208d78d5dff9cbe1348d28a1136b..4d333d26a02817dae863405bd7b4b9d9ca0d6e8e 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -219,9 +219,10 @@ getname_kernel(const char * filename)
        if (len <= EMBEDDED_NAME_MAX) {
                result->name = (char *)result->iname;
        } else if (len <= PATH_MAX) {
+               const size_t size = offsetof(struct filename, iname[1]);
                struct filename *tmp;
 
-               tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+               tmp = kmalloc(size, GFP_KERNEL);
                if (unlikely(!tmp)) {
                        __putname(result);
                        return ERR_PTR(-ENOMEM);