[PATCH] ubifs: log: Don't leak kernel memory to the MTD

[richard@xxxxxx (Richard Weinberger)]

ubifs_log_start_commit() allocates a buffer with kmalloc(),
this buffer is used to build UBIFS CS and REF nodes, all structure
attributes get set, except for the padding field in the ubifs_ref_node.
That way we leak 28 bytes of kernel memory to the MTD.
Fix it by using kzalloc().

Cc: stable at vger.kernel.org
Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard at nod.at>
---
 fs/ubifs/log.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c
index 7cffa120a750..60d49c6dd470 100644
--- a/fs/ubifs/log.c
+++ b/fs/ubifs/log.c
@@ -369,7 +369,7 @@ int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum)
 
 	max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ;
 	max_len = ALIGN(max_len, c->min_io_size);
-	buf = cs = kmalloc(max_len, GFP_NOFS);
+	buf = cs = kzalloc(max_len, GFP_NOFS);
 	if (!buf)
 		return -ENOMEM;
 
-- 
2.18.0