From 8e1943af2986db42bee2b8dddf49a36cdb2e9219 Mon Sep 17 00:00:00 2001
From: Pan Bian <bianpan2016@163.com>
Date: Wed, 17 Apr 2019 16:28:37 +0800
Subject: [PATCH] mmc: core: fix possible use after free of host
Git-commit: 8e1943af2986db42bee2b8dddf49a36cdb2e9219
Patch-mainline: v5.2-rc1
References: bsc#1051510
In the function mmc_alloc_host, the function put_device is called to
release allocated resources when mmc_gpio_alloc fails. Finally, the
function pointed by host->class_dev.class->dev_release (i.e.,
mmc_host_classdev_release) is used to release resources including the
host structure. However, after put_device, host is used and released
again. Resulting in a use-after-free bug.
Fixes: 1ed217194488 ("mmc: core: fix error path in mmc_host_alloc")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/mmc/core/host.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index b3fa9c916142..6a51f7a06ce7 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -429,8 +429,6 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
if (mmc_gpio_alloc(host)) {
put_device(&host->class_dev);
- ida_simple_remove(&mmc_host_ida, host->index);
- kfree(host);
return NULL;
}
--
2.16.4