Forwarded: [PATCH] hfsplus: fix memory leak in hfsplus_fill_super() error path

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Subject: [PATCH] hfsplus: fix memory leak in hfsplus_fill_super() error path
Author: kartikey406@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

When hfsplus_fill_super() fails, the sbi structure is freed but neither
sb->s_fs_info nor fc->s_fs_info are set to NULL. Since sget_fc() copies
fc->s_fs_info to sb->s_fs_info without clearing fc->s_fs_info, both
pointers reference the same memory. After fill_super frees sbi,
hfsplus_free_fc() may operate on a dangling pointer, causing memory
leak or other issues.

Set both sb->s_fs_info and fc->s_fs_info to NULL after freeing sbi
in the error path to ensure proper cleanup.

Reported-by: syzbot+99f6ed51479b86ac4c41@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=99f6ed51479b86ac4c41
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
---
 fs/hfsplus/super.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 54e85e25a259..f242b88f6633 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -630,6 +630,8 @@ static int hfsplus_fill_super(struct super_block *sb, struct fs_context *fc)
 	unload_nls(sbi->nls);
 	unload_nls(nls);
 	kfree(sbi);
+	sb->s_fs_info = NULL;
+	fc->s_fs_info = NULL;
 	return err;
 }
 
-- 
2.43.0