nvmem: core: Fix cell lookup when no cell is found (1c832674) · Commits · 戴 / test

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

+10 −6

Original line number	Diff line number	Diff line
		@@ -525,13 +525,15 @@ 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);

		return cell;
		@@ -994,13 +996,15 @@ 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);

		return cell;

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