4.19-stable review patch. If anyone has any objections, please let me know.
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From: Geert Uytterhoeven geert+renesas@glider.be
[ Upstream commit 4a6756f56bcf8e64c87144a626ce53aea4899c0e ]
When obtaining one or more optional resets, non-existent resets are stored as NULL pointers, and all related error and cleanup paths need to take this into account.
Currently only reset_control_put() and reset_control_bulk_put() get this right. All of __reset_control_bulk_get(), of_reset_control_array_get(), and reset_control_array_put() lack the proper checking, causing NULL pointer dereferences on failure or release.
Fix this by moving the existing check from reset_control_bulk_put() to __reset_control_put_internal(), so it applies to all callers. The double check in reset_control_put() doesn't hurt.
Fixes: 17c82e206d2a3cd8 ("reset: Add APIs to manage array of resets") Fixes: 48d71395896d54ee ("reset: Add reset_control_bulk API") Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be Link: https://lore.kernel.org/r/2440edae7ca8534628cdbaf559ded288f2998178.170127680... Signed-off-by: Philipp Zabel p.zabel@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/reset/core.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/reset/core.c b/drivers/reset/core.c index ccb97f4e31c38..1680d27040c9b 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -459,6 +459,9 @@ static void __reset_control_put_internal(struct reset_control *rstc) { lockdep_assert_held(&reset_list_mutex);
+ if (IS_ERR_OR_NULL(rstc)) + return; + kref_put(&rstc->refcnt, __reset_control_release); }