[PATCH 6.1 331/473] stm class: Fix a double free in stm_register_device()

Greg Kroah-Hartman
2024-06-06T14:17:27Z

From: Dan Carpenter <dan.carpenter@linaro.org>

[ Upstream commit 3df463865ba42b8f88a590326f4c9ea17a1ce459 ]

The put_device(&stm->dev) call will trigger stm_device_release() which
frees "stm" so the vfree(stm) on the next line is a double free.

Fixes: 389b6699a2aa ("stm class: Fix stm device initialization order")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20240429130119.1518073-2-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/hwtracing/stm/core.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index 2712e699ba08c..ae9ea3a1fa2aa 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -868,8 +868,11 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data,
return -ENOMEM;

stm->major = register_chrdev(0, stm_data->name, &stm_fops);
- if (stm->major < 0)
- goto err_free;
+ if (stm->major < 0) {
+ err = stm->major;
+ vfree(stm);
+ return err;
+ }

device_initialize(&stm->dev);
stm->dev.devt = MKDEV(stm->major, 0);
@@ -913,10 +916,8 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data,
err_device:
unregister_chrdev(stm->major, stm_data->name);

- /* matches device_initialize() above */
+ /* calls stm_device_release() */
put_device(&stm->dev);
-err_free:
- vfree(stm);

return err;
}
--
2.43.0