[PATCH] nvmem: core: Fix memleak in nvmem_register()

[PATCH] nvmem: core: Fix memleak in nvmem_register()

[Srinivas Kandagatla]

From: Gaosheng Cui <cuigaosheng1@huawei.com>

dev_set_name will alloc memory for nvmem->dev.kobj.name in
nvmem_register, when nvmem_validate_keepouts failed, nvmem's
memory will be freed and return, but nobody will free memory
for nvmem->dev.kobj.name, there will be memleak, so moving
nvmem_validate_keepouts() after device_register() and let
the device core deal with cleaning name in error cases.

Fixes: de0534df9347 ("nvmem: core: fix error handling while validating keepout regions")
Cc: stable@vger.kernel.org
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
Hi Greg,

Here is a fix in nvmem core which can possibly go in next rc.
Could you please pick this up.

thanks,
Srini

 drivers/nvmem/core.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 1e3c754efd0d..2164efd12ba9 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -829,21 +829,18 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
 	nvmem->dev.groups = nvmem_dev_groups;
 #endif
 
-	if (nvmem->nkeepout) {
-		rval = nvmem_validate_keepouts(nvmem);
-		if (rval) {
-			ida_free(&nvmem_ida, nvmem->id);
-			kfree(nvmem);
-			return ERR_PTR(rval);
-		}
-	}
-
 	dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name);
 
 	rval = device_register(&nvmem->dev);
 	if (rval)
 		goto err_put_device;
 
+	if (nvmem->nkeepout) {
+		rval = nvmem_validate_keepouts(nvmem);
+		if (rval)
+			goto err_device_del;
+	}
+
 	if (config->compat) {
 		rval = nvmem_sysfs_setup_compat(nvmem, config);
 		if (rval)
-- 
2.25.1

Re: [PATCH] nvmem: core: Fix memleak in nvmem_register()

[Greg KH]

On Fri, Sep 16, 2022 at 01:04:02PM +0100, Srinivas Kandagatla wrote:
> From: Gaosheng Cui <cuigaosheng1@huawei.com>
> 
> dev_set_name will alloc memory for nvmem->dev.kobj.name in
> nvmem_register, when nvmem_validate_keepouts failed, nvmem's
> memory will be freed and return, but nobody will free memory
> for nvmem->dev.kobj.name, there will be memleak, so moving
> nvmem_validate_keepouts() after device_register() and let
> the device core deal with cleaning name in error cases.
> 
> Fixes: de0534df9347 ("nvmem: core: fix error handling while validating keepout regions")
> Cc: stable@vger.kernel.org
> Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
> Hi Greg,
> 
> Here is a fix in nvmem core which can possibly go in next rc.
> Could you please pick this up.

I missed this for 6.0-final, but as it's only on a not-ever-hit error
path, it can wait for 6.1-rc1.

thanks,

greg k-h