[PATCH][V3] ARM: pmu: fix memory leak due to early return not freeing irqs

[PATCH][V3] ARM: pmu: fix memory leak due to early return not freeing irqs

[Colin King]

From: Colin Ian King <colin.king@canonical.com>

Recent commit 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about
missing interrupt-affinity property for PPIs") introduced a memory
leak of irqs on the "Don't bother with PPIs" return path. This issue
was picked up by static analysis by cppcheck:

[arch/arm/kernel/perf_event_cpu.c:315]: (error) Memory leak: irqs

Instead, perform allocation of irqs after getting the irq hence
removing need to clean up an allocation on the PPI affine return path.

Fixes: 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about missing interrupt-affinity property for PPIs")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 arch/arm/kernel/perf_event_cpu.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 213919b..a7099ee 100644
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -303,17 +303,17 @@ static int probe_current_pmu(struct arm_pmu *pmu)
 
 static int of_pmu_irq_cfg(struct platform_device *pdev)
 {
-	int i, irq;
-	int *irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
-
-	if (!irqs)
-		return -ENOMEM;
+	int i, irq, *irqs;
 
 	/* Don't bother with PPIs; they're already affine */
 	irq = platform_get_irq(pdev, 0);
 	if (irq >= 0 && irq_is_percpu(irq))
 		return 0;
 
+	irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
+	if (!irqs)
+		return -ENOMEM;
+
 	for (i = 0; i < pdev->num_resources; ++i) {
 		struct device_node *dn;
 		int cpu;
-- 
2.1.4

[PATCH][V3] ARM: pmu: fix memory leak due to early return not freeing irqs

[Colin Ian King]

On 18/05/15 14:27, Sudeep Holla wrote:
> 
> 
> On 18/05/15 13:57, Colin King wrote:
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> Recent commit 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about
>> missing interrupt-affinity property for PPIs") introduced a memory
>> leak of irqs on the "Don't bother with PPIs" return path. This issue
>> was picked up by static analysis by cppcheck:
>>
>> [arch/arm/kernel/perf_event_cpu.c:315]: (error) Memory leak: irqs
>>
>> Instead, perform allocation of irqs after getting the irq hence
>> removing need to clean up an allocation on the PPI affine return path.
>>
>> Fixes: 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about missing
>> interrupt-affinity property for PPIs")
> 
> Will Deacon has similar patch[1] in Russell's patch tracker(8357/1)
> 
> Regards,
> Sudeep

OK, sorry for the dup and noise.

> 
> [1]
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-May/342367.html
> [2] http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8357/1

[PATCH][V3] ARM: pmu: fix memory leak due to early return not freeing irqs

[Sudeep Holla]

On 18/05/15 13:57, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> Recent commit 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about
> missing interrupt-affinity property for PPIs") introduced a memory
> leak of irqs on the "Don't bother with PPIs" return path. This issue
> was picked up by static analysis by cppcheck:
>
> [arch/arm/kernel/perf_event_cpu.c:315]: (error) Memory leak: irqs
>
> Instead, perform allocation of irqs after getting the irq hence
> removing need to clean up an allocation on the PPI affine return path.
>
> Fixes: 338d9dd3e2ae ("ARM: 8351/1: perf: don't warn about missing interrupt-affinity property for PPIs")

Will Deacon has similar patch[1] in Russell's patch tracker(8357/1)

Regards,
Sudeep

[1] 
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-May/342367.html
[2] http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8357/1