c/r: prctl: add minimal address test to PR_SET_MM

Make sure the address being set is greater than mmap_min_addr (as
suggested by Kees Cook).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index 54f20fdee93c..19a2c7139960 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1869,7 +1869,7 @@ static int prctl_set_mm(int opt, unsigned long addr,
         if (opt == PR_SET_MM_EXE_FILE)
                 return prctl_set_mm_exe_file(mm, (unsigned int)addr);
 
-        if (addr >= TASK_SIZE)
+        if (addr >= TASK_SIZE || addr < mmap_min_addr)
                 return -EINVAL;
 
         error = -EINVAL;