[PATCH 5.15.y] fs/ntfs3: Initialize allocated memory before use

Li hongliang posted 1 patch 1 week, 5 days ago
fs/ntfs3/inode.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
[PATCH 5.15.y] fs/ntfs3: Initialize allocated memory before use
Posted by Li hongliang 1 week, 5 days ago
From: Bartlomiej Kubik <kubik.bartlomiej@gmail.com>

[ Upstream commit a8a3ca23bbd9d849308a7921a049330dc6c91398 ]

KMSAN reports: Multiple uninitialized values detected:

- KMSAN: uninit-value in ntfs_read_hdr (3)
- KMSAN: uninit-value in bcmp (3)

Memory is allocated by __getname(), which is a wrapper for
kmem_cache_alloc(). This memory is used before being properly
cleared. Change kmem_cache_alloc() to kmem_cache_zalloc() to
properly allocate and clear memory before use.

Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block")
Fixes: 78ab59fee07f ("fs/ntfs3: Rework file operations")
Tested-by: syzbot+332bd4e9d148f11a87dc@syzkaller.appspotmail.com
Reported-by: syzbot+332bd4e9d148f11a87dc@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=332bd4e9d148f11a87dc

Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block")
Fixes: 78ab59fee07f ("fs/ntfs3: Rework file operations")
Tested-by: syzbot+0399100e525dd9696764@syzkaller.appspotmail.com
Reported-by: syzbot+0399100e525dd9696764@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0399100e525dd9696764

Reviewed-by: Khalid Aziz <khalid@kernel.org>
Signed-off-by: Bartlomiej Kubik <kubik.bartlomiej@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Li hongliang <1468888505@139.com>
---
 fs/ntfs3/inode.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 7ac76e6c35dc..acd5be0d36c0 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -1298,7 +1298,7 @@ struct inode *ntfs_create_inode(struct user_namespace *mnt_userns,
 		fa |= FILE_ATTRIBUTE_READONLY;
 
 	/* Allocate PATH_MAX bytes. */
-	new_de = __getname();
+	new_de = kmem_cache_zalloc(names_cachep, GFP_KERNEL);
 	if (!new_de) {
 		err = -ENOMEM;
 		goto out1;
@@ -1694,10 +1694,9 @@ int ntfs_link_inode(struct inode *inode, struct dentry *dentry)
 	struct ATTR_FILE_NAME *de_name;
 
 	/* Allocate PATH_MAX bytes. */
-	de = __getname();
+	de = kmem_cache_zalloc(names_cachep, GFP_KERNEL);
 	if (!de)
 		return -ENOMEM;
-	memset(de, 0, PATH_MAX);
 
 	/* Mark rw ntfs as dirty. It will be cleared at umount. */
 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
@@ -1742,7 +1741,7 @@ int ntfs_unlink_inode(struct inode *dir, const struct dentry *dentry)
 		return -EINVAL;
 
 	/* Allocate PATH_MAX bytes. */
-	de = __getname();
+	de = kmem_cache_zalloc(names_cachep, GFP_KERNEL);
 	if (!de)
 		return -ENOMEM;
 
-- 
2.34.1