From 1c83267473b881cf75247acf1129456ef33aba86 Mon Sep 17 00:00:00 2001
From: Alban Bedel <albeu@free.fr>
Date: Mon, 28 Jan 2019 15:55:02 +0000
Subject: [PATCH] nvmem: core: Fix cell lookup when no cell is found
If the cell list is not empty and nvmem_find_cell_by_node/name() is
called for a cell that is not present in the list they will return an
invalid pointer instead of NULL. This happen because
list_for_each_entry() stop once it reach the list head again, but as
the list head is not contained in a struct nvmem_cell the iteration
variable then contains an invalid value.
This is easily solved by using a variable to iterate over the list and
one to return the cell found.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/nvmem/core.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index f8c43da6f2ca7..a2ad44104aa22 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -525,12 +525,14 @@ out:
static struct nvmem_cell *
nvmem_find_cell_by_name(struct nvmem_device *nvmem, const char *cell_id)
{
- struct nvmem_cell *cell = NULL;
+ struct nvmem_cell *iter, *cell = NULL;
mutex_lock(&nvmem_mutex);
- list_for_each_entry(cell, &nvmem->cells, node) {
- if (strcmp(cell_id, cell->name) == 0)
+ list_for_each_entry(iter, &nvmem->cells, node) {
+ if (strcmp(cell_id, iter->name) == 0) {
+ cell = iter;
break;
+ }
}
mutex_unlock(&nvmem_mutex);
@@ -994,12 +996,14 @@ out:
static struct nvmem_cell *
nvmem_find_cell_by_node(struct nvmem_device *nvmem, struct device_node *np)
{
- struct nvmem_cell *cell = NULL;
+ struct nvmem_cell *iter, *cell = NULL;
mutex_lock(&nvmem_mutex);
- list_for_each_entry(cell, &nvmem->cells, node) {
- if (np == cell->np)
+ list_for_each_entry(iter, &nvmem->cells, node) {
+ if (np == iter->np) {
+ cell = iter;
break;
+ }
}
mutex_unlock(&nvmem_mutex);
--
2.30.2