[PATCH v2 4/4] pstore: inode: Use cleanup.h for struct pstore_private

From: Kees Cook
Date: Tue Dec 05 2023 - 13:26:32 EST


Simplify error path when "private" needs to be freed.

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 | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index a27764341079..d0d9bfdad30c 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -63,6 +63,7 @@ static void free_pstore_private(struct pstore_private *private)
}
kfree(private);
}
+DEFINE_FREE(pstore_private, struct pstore_private *, free_pstore_private(_T));

static void *pstore_ftrace_seq_start(struct seq_file *s, loff_t *pos)
{
@@ -340,9 +341,8 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)
{
struct dentry *dentry;
struct inode *inode __free(pstore_iput) = NULL;
- int rc = 0;
char name[PSTORE_NAMELEN];
- struct pstore_private *private, *pos;
+ struct pstore_private *private __free(pstore_private) = NULL, *pos;
size_t size = record->size + record->ecc_notice_size;

if (WARN_ON(!inode_is_locked(d_inode(root))))
@@ -358,7 +358,6 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)
return -EEXIST;
}

- rc = -ENOMEM;
inode = pstore_get_inode(root->d_sb);
if (!inode)
return -ENOMEM;
@@ -375,7 +374,7 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)

dentry = d_alloc_name(root, name);
if (!dentry)
- goto fail_private;
+ return -ENOMEM;

private->dentry = dentry;
private->record = record;
@@ -388,13 +387,9 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)

d_add(dentry, no_free_ptr(inode));

- list_add(&private->list, &records_list);
+ list_add(&(no_free_ptr(private))->list, &records_list);

return 0;
-
-fail_private:
- free_pstore_private(private);
- return rc;
}

/*
--
2.34.1