[PATCH 5.13 161/800] arm64: perf: Convert snprintf to sysfs_emit

[Greg Kroah-Hartman]

From: Tian Tao <tiantao6@xxxxxxxxxxxxx>

[ Upstream commit a5740e955540181f4ab8f076cc9795c6bbe4d730 ]

Use sysfs_emit instead of snprintf to avoid buf overrun,because in
sysfs_emit it strictly checks whether buf is null or buf whether
pagesize aligned, otherwise it returns an error.

Signed-off-by: Tian Tao <tiantao6@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1621497585-30887-1-git-send-email-tiantao6@xxxxxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/arm64/kernel/perf_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index f594957e29bd..44b6eda69a81 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -312,7 +312,7 @@ static ssize_t slots_show(struct device *dev, struct device_attribute *attr,
 	struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
 	u32 slots = cpu_pmu->reg_pmmir & ARMV8_PMU_SLOTS_MASK;
 
-	return snprintf(page, PAGE_SIZE, "0x%08x\n", slots);
+	return sysfs_emit(page, "0x%08x\n", slots);
 }
 
 static DEVICE_ATTR_RO(slots);
-- 
2.30.2