4.19-stable review patch. If anyone has any objections, please let me know.
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From: Hagar Hemdan hagarhem@amazon.com
[ Upstream commit adec57ff8e66aee632f3dd1f93787c13d112b7a1 ]
In create_pinctrl(), pinctrl_maps_mutex is acquired before calling add_setting(). If add_setting() returns -EPROBE_DEFER, create_pinctrl() calls pinctrl_free(). However, pinctrl_free() attempts to acquire pinctrl_maps_mutex, which is already held by create_pinctrl(), leading to a potential deadlock.
This patch resolves the issue by releasing pinctrl_maps_mutex before calling pinctrl_free(), preventing the deadlock.
This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc.
Fixes: 42fed7ba44e4 ("pinctrl: move subsystem mutex to pinctrl_dev struct") Suggested-by: Maximilian Heyne mheyne@amazon.de Signed-off-by: Hagar Hemdan hagarhem@amazon.com Link: https://lore.kernel.org/r/20240604085838.3344-1-hagarhem@amazon.com Signed-off-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pinctrl/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 052894d3a2047..97b1fa3a5e78d 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -1078,8 +1078,8 @@ static struct pinctrl *create_pinctrl(struct device *dev, * an -EPROBE_DEFER later, as that is the worst case. */ if (ret == -EPROBE_DEFER) { - pinctrl_free(p, false); mutex_unlock(&pinctrl_maps_mutex); + pinctrl_free(p, false); return ERR_PTR(ret); } }