[PATCH] pstore/zone: Fix return value in psz_init_zone() and psz_init_zones()

[hhtracer]

From: huhai <huhai@xxxxxxxxxx>

The psz_init_zone() and psz_init_zones() functions return NULL on error,
but psz_alloc_zones() only checks the return value using IS_ERR(). Since
NULL is not an error pointer, this causes psz_alloc_zones() to mistakenly
treat a failure as success and return 0, which may lead to a NULL pointer
dereference.

Update both psz_init_zone() and psz_init_zones() to return proper error
pointers using ERR_PTR() instead of NULL.

Fixes: d26c3321fe18 ("pstore/zone: Introduce common layer to manage storage zones")
Signed-off-by: huhai <huhai@xxxxxxxxxx>
---
 fs/pstore/zone.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c
index ceb5639a0629..57ffcf76f254 100644
--- a/fs/pstore/zone.c
+++ b/fs/pstore/zone.c
@@ -1157,7 +1157,7 @@ static struct pstore_zone *psz_init_zone(enum pstore_type_id type,
 	const char *name = pstore_type_to_name(type);
 
 	if (!size)
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	if (*off + size > info->total_size) {
 		pr_err("no room for %s (0x%zx@0x%llx over 0x%lx)\n",
@@ -1203,7 +1203,7 @@ static struct pstore_zone **psz_init_zones(enum pstore_type_id type,
 
 	*cnt = 0;
 	if (!total_size || !record_size)
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	if (*off + total_size > info->total_size) {
 		pr_err("no room for zones %s (0x%zx@0x%llx over 0x%lx)\n",
@@ -1225,7 +1225,7 @@ static struct pstore_zone **psz_init_zones(enum pstore_type_id type,
 
 	for (i = 0; i < c; i++) {
 		zone = psz_init_zone(type, off, record_size);
-		if (!zone || IS_ERR(zone)) {
+		if (IS_ERR(zone)) {
 			pr_err("initialize zones %s failed\n", name);
 			psz_free_zones(&zones, &i);
 			return (void *)zone;
-- 
2.25.1