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From:   Shigeru Yoshida <syoshida@redhat.com>
To:     almaz.alexandrovich@paragon-software.com
Cc:     ntfs3@lists.linux.dev, linux-kernel@vger.kernel.org,
        Shigeru Yoshida <syoshida@redhat.com>,
        syzbot+9d67170b20e8f94351c8@syzkaller.appspotmail.com
Subject: [PATCH] fs/ntfs3: Fix memory leak on ntfs_fill_super() error path
Date:   Tue, 23 Aug 2022 19:32:05 +0900
Message-Id: <20220823103205.1380235-1-syoshida@redhat.com>
MIME-Version: 1.0
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syzbot reported kmemleak as below:

BUG: memory leak
unreferenced object 0xffff8880122f1540 (size 32):
  comm "a.out", pid 6664, jiffies 4294939771 (age 25.500s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 ed ff ed ff 00 00 00 00  ................
  backtrace:
    [<ffffffff81b16052>] ntfs_init_fs_context+0x22/0x1c0
    [<ffffffff8164aaa7>] alloc_fs_context+0x217/0x430
    [<ffffffff81626dd4>] path_mount+0x704/0x1080
    [<ffffffff81627e7c>] __x64_sys_mount+0x18c/0x1d0
    [<ffffffff84593e14>] do_syscall_64+0x34/0xb0
    [<ffffffff84600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

This patch fixes this issue by freeing mount options on error path of
ntfs_fill_super().

Reported-by: syzbot+9d67170b20e8f94351c8@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
---
 fs/ntfs3/super.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 47012c9bf505..c0e45f170701 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -1281,6 +1281,7 @@ static int ntfs_fill_super(struct super_block *sb, struct fs_context *fc)
 	 * Free resources here.
 	 * ntfs_fs_free will be called with fc->s_fs_info = NULL
 	 */
+	put_mount_options(sbi->options);
 	put_ntfs(sbi);
 	sb->s_fs_info = NULL;
 
-- 
2.37.2