[PATCH] powerpc/imc-pmu: Fix null pointer dereference in update_events_in_group

[Kunwu Chan]

kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.

Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Kunwu Chan <chen...@kylinos.cn>
---
 arch/powerpc/perf/imc-pmu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 5d12ca386c1f..8664a7d297ad 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -299,6 +299,8 @@ static int update_events_in_group(struct device_node *node, 
struct imc_pmu *pmu)
        attr_group->attrs = attrs;
        do {
                ev_val_str = kasprintf(GFP_KERNEL, "event=0x%x", 
pmu->events[i].value);
+               if (!ev_val_str)
+                       continue;
                dev_str = device_str_attr_create(pmu->events[i].name, 
ev_val_str);
                if (!dev_str)
                        continue;
@@ -306,6 +308,8 @@ static int update_events_in_group(struct device_node *node, 
struct imc_pmu *pmu)
                attrs[j++] = dev_str;
                if (pmu->events[i].scale) {
                        ev_scale_str = kasprintf(GFP_KERNEL, "%s.scale", 
pmu->events[i].name);
+                       if (!ev_scale_str)
+                               continue;
                        dev_str = device_str_attr_create(ev_scale_str, 
pmu->events[i].scale);
                        if (!dev_str)
                                continue;
@@ -315,6 +319,8 @@ static int update_events_in_group(struct device_node *node, 
struct imc_pmu *pmu)
 
                if (pmu->events[i].unit) {
                        ev_unit_str = kasprintf(GFP_KERNEL, "%s.unit", 
pmu->events[i].name);
+                       if (!ev_unit_str)
+                               continue;
                        dev_str = device_str_attr_create(ev_unit_str, 
pmu->events[i].unit);
                        if (!dev_str)
                                continue;
-- 
2.34.1