fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info()
[ Upstream commit 1d605416fb7175e1adf094251466caa52093b413 ]
KMSAN reported uninitialized data being written to disk when dumping
core. As a result, several kilobytes of kmalloc memory may be written
to the core file and then read by a non-privileged user.
Reported-by: sam <sunhaoyl@outlook.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200419100848.63472-1-glider@google.com
Link: https://github.com/google/kmsan/issues/76
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index e7fd0b5..975dd0d 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1766,7 +1766,7 @@
(!regset->active || regset->active(t->task, regset) > 0)) {
int ret;
size_t size = regset_size(t->task, regset);
- void *data = kmalloc(size, GFP_KERNEL);
+ void *data = kzalloc(size, GFP_KERNEL);
if (unlikely(!data))
return 0;
ret = regset->get(t->task, regset,
