The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 2eead19334516c8e9927c11b448fbe512b1f18a1 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025102641-epilogue-pronto-38c8@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 2eead19334516c8e9927c11b448fbe512b1f18a1 Mon Sep 17 00:00:00 2001 From: Kaushlendra Kumar kaushlendra.kumar@intel.com Date: Tue, 23 Sep 2025 23:13:08 +0530 Subject: [PATCH] arch_topology: Fix incorrect error check in topology_parse_cpu_capacity()

Fix incorrect use of PTR_ERR_OR_ZERO() in topology_parse_cpu_capacity() which causes the code to proceed with NULL clock pointers. The current logic uses !PTR_ERR_OR_ZERO(cpu_clk) which evaluates to true for both valid pointers and NULL, leading to potential NULL pointer dereference in clk_get_rate().

Per include/linux/err.h documentation, PTR_ERR_OR_ZERO(ptr) returns: "The error code within @ptr if it is an error pointer; 0 otherwise."

This means PTR_ERR_OR_ZERO() returns 0 for both valid pointers AND NULL pointers. Therefore !PTR_ERR_OR_ZERO(cpu_clk) evaluates to true (proceed) when cpu_clk is either valid or NULL, causing clk_get_rate(NULL) to be called when of_clk_get() returns NULL.

Replace with !IS_ERR_OR_NULL(cpu_clk) which only proceeds for valid pointers, preventing potential NULL pointer dereference in clk_get_rate().

Cc: stable stable@kernel.org Signed-off-by: Kaushlendra Kumar kaushlendra.kumar@intel.com Reviewed-by: Sudeep Holla sudeep.holla@arm.com Fixes: b8fe128dad8f ("arch_topology: Adjust initial CPU capacities with current freq") Link: https://patch.msgid.link/20250923174308.1771906-1-kaushlendra.kumar@intel.co... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 1037169abb45..e1eff05bea4a 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -292,7 +292,7 @@ bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu) * frequency (by keeping the initial capacity_freq_ref value). */ cpu_clk = of_clk_get(cpu_node, 0); - if (!PTR_ERR_OR_ZERO(cpu_clk)) { + if (!IS_ERR_OR_NULL(cpu_clk)) { per_cpu(capacity_freq_ref, cpu) = clk_get_rate(cpu_clk) / HZ_PER_KHZ; clk_put(cpu_clk);