perf: arm_spe: handle devm_kasprintf() failure

devm_kasprintf() may return NULL on failure of internal allocation
thus the assignment to 'name' is not safe if unchecked. If NULL
is passed in for name then perf_pmu_register() would not fail
but rather silently jump to skip_type which is not the intent
here. As perf_pmu_register() may also return -ENOMEM returning
-ENOMEM in the (unlikely) failure case of devm_kasprintf() should
be fine here as well.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Fixes: d5d9696b0380 ("drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[will: reworded error message]
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index 18d61077b157ae823188f4d4842b7a5037f1100d..8e46a9dad2fa2880ce629c8279ada5fa6ed54701 100644 (file)
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -927,6 +927,11 @@ static int arm_spe_pmu_perf_init(struct arm_spe_pmu *spe_pmu)
 
        idx = atomic_inc_return(&pmu_idx);
        name = devm_kasprintf(dev, GFP_KERNEL, "%s_%d", PMUNAME, idx);
+       if (!name) {
+               dev_err(dev, "failed to allocate name for pmu %d\n", idx);
+               return -ENOMEM;
+       }
+
        return perf_pmu_register(&spe_pmu->pmu, name, -1);
 }