inode.c: Fix incorrect variable freeing.

Hi,

In ramfs_fill_super(), if fsi's memory allocation fails, it will go to 'fail', which immediately tries to free the variable, potentially producing an Oops. This patch addresses this issue.

Thanks.

Signed-off-by Davidlohr Bueso <[email protected]>

---
 fs/ramfs/inode.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

fs/ramfs/inode.c +1 -3

index a5ebae7..40af7a2 100644
@@ -219,7 +219,7 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_fs_info = fsi;
 	if (!fsi) {
 		err = -ENOMEM;
-		goto fail;
+		goto fail2;
 	}
 
 	err = ramfs_parse_options(data, &fsi->mount_opts);

@@ -247,11 +247,13 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent)
 	}
 
 	return 0;
-fail:
-	kfree(fsi);

Quoted 41 lines · On Sun, 20 Jun 2010 15:27:37 -0400 Davidlohr Bueso <[email protected]> wrote:

Hi,

In ramfs_fill_super(), if fsi's memory allocation fails, it will go to 'fail', which immediately tries to free the variable, potentially producing an Oops. This patch addresses this issue.

Thanks.

Signed-off-by Davidlohr Bueso <[email protected]>

---
 fs/ramfs/inode.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

fs/ramfs/inode.c +5 -3

index a5ebae7..40af7a2 100644
@@ -219,7 +219,7 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_fs_info = fsi;
 	if (!fsi) {
 		err = -ENOMEM;
-		goto fail;
+		goto fail2;
 	}
 
 	err = ramfs_parse_options(data, &fsi->mount_opts);

@@ -247,11 +247,13 @@ int ramfs_fill_super(struct super_block *sb, void *data, int silent)
 	}
 
 	return 0;
-fail:
-	kfree(fsi);
+fail2:
 	sb->s_fs_info = NULL;
 	iput(inode);
 	return err;
+fail:
+	kfree(fsi);
+	goto fail2;
 }
 

fs/ramfs/inode.c int ramfs_fill_super(struct super_block *sb, void *data, int silent) · line 259

Quoted 1 line

fs/ramfs/inode.c +0 -0

 int ramfs_get_sb(struct file_system_type *fs_type,

notabug. kfree(NULL) is an OK thing to do. The kernel does this pretty regularly in recovery paths - it usually results in slightly simpler and slightly smaller code.