From: Navid Emamdoost <navid.emamdoost@gmail.com>
Date: Wed, 2 Oct 2019 21:52:37 +0000 (-0500)
Subject: affs: fix a memory leak in affs_remount
X-Git-Tag: v5.5-rc1~194^2
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=450c3d4166837c496ebce03650c08800991f2150;p=linux.git

affs: fix a memory leak in affs_remount

In affs_remount if data is provided it is duplicated into new_opts.  The
allocated memory for new_opts is only released if parse_options fails.

There's a bit of history behind new_options, originally there was
save/replace options on the VFS layer so the 'data' passed must not
change (thus strdup), this got cleaned up in later patches. But not
completely.

There's no reason to do the strdup in cases where the filesystem does
not need to reuse the 'data' again, because strsep would modify it
directly.

Fixes: c8f33d0bec99 ("affs: kstrdup() memory handling")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/affs/super.c b/fs/affs/super.c
index 9fcff55c65af..47107c6712a6 100644
--- a/fs/affs/super.c
+++ b/fs/affs/super.c
@@ -561,14 +561,9 @@ affs_remount(struct super_block *sb, int *flags, char *data)
 	int			 root_block;
 	unsigned long		 mount_flags;
 	int			 res = 0;
-	char			*new_opts;
 	char			 volume[32];
 	char			*prefix = NULL;
 
-	new_opts = kstrdup(data, GFP_KERNEL);
-	if (data && !new_opts)
-		return -ENOMEM;
-
 	pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);
 
 	sync_filesystem(sb);
@@ -579,7 +574,6 @@ affs_remount(struct super_block *sb, int *flags, char *data)
 			   &blocksize, &prefix, volume,
 			   &mount_flags)) {
 		kfree(prefix);
-		kfree(new_opts);
 		return -EINVAL;
 	}