vsprintf: Prevent crash when dereferencing invalid pointers for %pD

Commit 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid
pointers") prevents most crash except for %pD.
There is an additional pointer dereferencing before dentry_name.

At least, vma->file can be NULL and be passed to printk %pD in
print_bad_pte, which can cause crash.

This patch fixes it with introducing a new file_dentry_name.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers")
To: Geert Uytterhoeven <[email protected]>
To: Thomas Gleixner <[email protected]>
To: Andy Shevchenko <[email protected]>
To: [email protected]
Cc: Kees Cook <[email protected]>
Cc: "Steven Rostedt (VMware)" <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: "Tobin C. Harding" <[email protected]>
Signed-off-by: Jia He <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Reviewed-by: Sergey Senozhatsky <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>

0 files changed, 0 insertions, 0 deletions