[PATCH 1/5] pstore: inode: Convert kfree() usage to __free(kfree)

From: Kees Cook
Date: Sat Dec 02 2023 - 16:22:42 EST


Mostly as an example to myself, replace a simple allocation pattern with
the automatic kfree cleanup features now exposed by cleanup.h.

Cc: "Guilherme G. Piccoli" <gpiccoli@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: linux-hardening@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
fs/pstore/inode.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index d41c20d1b5e8..20f3452c8196 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -23,6 +23,7 @@
#include <linux/pstore.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
+#include <linux/cleanup.h>

#include "internal.h"

@@ -64,7 +65,7 @@ static void free_pstore_private(struct pstore_private *private)
static void *pstore_ftrace_seq_start(struct seq_file *s, loff_t *pos)
{
struct pstore_private *ps = s->private;
- struct pstore_ftrace_seq_data *data;
+ struct pstore_ftrace_seq_data *data __free(kfree) = NULL;

data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
@@ -72,13 +73,10 @@ static void *pstore_ftrace_seq_start(struct seq_file *s, loff_t *pos)

data->off = ps->total_size % REC_SIZE;
data->off += *pos * REC_SIZE;
- if (data->off + REC_SIZE > ps->total_size) {
- kfree(data);
+ if (data->off + REC_SIZE > ps->total_size)
return NULL;
- }
-
- return data;

+ return_ptr(data);
}

static void pstore_ftrace_seq_stop(struct seq_file *s, void *v)
--
2.34.1