[Linux-kernel-mentees] [PATCH] hfs, hfsplus: Fix NULL pointer dereference in hfs_find_init()

[Peilin Ye]

Prevent hfs_find_init() from dereferencing `tree` as NULL.

Reported-and-tested-by: syzbot+7ca256d0da4af073b2e2 at syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <yepeilin.cs at gmail.com>
---
 fs/hfs/bfind.c     | 3 +++
 fs/hfsplus/bfind.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/fs/hfs/bfind.c b/fs/hfs/bfind.c
index 4af318fbda77..880b7ea2c0fc 100644
--- a/fs/hfs/bfind.c
+++ b/fs/hfs/bfind.c
@@ -16,6 +16,9 @@ int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
 {
 	void *ptr;
 
+	if (!tree)
+		return -EINVAL;
+
 	fd->tree = tree;
 	fd->bnode = NULL;
 	ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
diff --git a/fs/hfsplus/bfind.c b/fs/hfsplus/bfind.c
index ca2ba8c9f82e..85bef3e44d7a 100644
--- a/fs/hfsplus/bfind.c
+++ b/fs/hfsplus/bfind.c
@@ -16,6 +16,9 @@ int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
 {
 	void *ptr;
 
+	if (!tree)
+		return -EINVAL;
+
 	fd->tree = tree;
 	fd->bnode = NULL;
 	ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
-- 
2.25.1