[PATCH v3 2/5] nvmem: core: initialise nvmem->id early Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>,Gaosheng Cui <cuigaosheng1@xxxxxxxxxx>,Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>,linux-arm-kernel@xxxxxxxxxxxxxxxxxxx,linux-kernel@xxxxxxxxxxxxxxx,Maxime Ripard <mripard@xxxxxxxxxx>, Hector Martin <marcan@xxxxxxxxx>

From: Russell King (Oracle)
Date: Tue Jan 03 2023 - 11:59:32 EST


The error path for wp_gpio attempts to free the IDA nvmem->id, but
this has yet to be assigned, so will always be zero - leaking the
ID allocated by ida_alloc(). Fix this by moving the initialisation
of nvmem->id earlier.

Fixes: f7d8d7dcd978 ("nvmem: fix memory leak in error path")
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
---
drivers/nvmem/core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index bf11e0c36d60..c1a40d9c3825 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -770,6 +770,8 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
return ERR_PTR(rval);
}

+ nvmem->id = rval;
+
if (config->wp_gpio)
nvmem->wp_gpio = config->wp_gpio;
else if (!config->ignore_wp)
@@ -785,7 +787,6 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
kref_init(&nvmem->refcnt);
INIT_LIST_HEAD(&nvmem->cells);

- nvmem->id = rval;
nvmem->owner = config->owner;
if (!nvmem->owner && config->dev->driver)
nvmem->owner = config->dev->driver->owner;
--
2.30.2