6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kaushlendra Kumar kaushlendra.kumar@intel.com
commit 2eead19334516c8e9927c11b448fbe512b1f18a1 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/base/arch_topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -326,7 +326,7 @@ bool __init topology_parse_cpu_capacity( * 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);