From: Xu Wang <vulab@iscas.ac.cn> stable inclusion from stable-v5.10.137 commit 81cb31756888bb062e92d2dca21cd629d77a46a9 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit e4c72c06c367758a14f227c847f9d623f1994ecf ] Free the adap structure only after we are done using it. This patch just moves the put_device() down a bit to avoid the use after free. Fixes: 611e12ea0f12 ("i2c: core: manage i2c bus device refcount in i2c_[get|put]_adapter") Signed-off-by: Xu Wang <vulab@iscas.ac.cn> [wsa: added comment to the code, added Fixes tag] Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- drivers/i2c/i2c-core-base.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 8a996af91c12..40e05f762a1b 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -2452,8 +2452,9 @@ void i2c_put_adapter(struct i2c_adapter *adap) if (!adap) return; - put_device(&adap->dev); module_put(adap->owner); + /* Should be last, otherwise we risk use-after-free with 'adap' */ + put_device(&adap->dev); } EXPORT_SYMBOL(i2c_put_adapter); -- 2.20.1