[PATCH] ACPI: Replace sprintf with sysfs_emit

From: Sumeet Pawnikar

Date: Mon Jan 26 2026 - 04:40:10 EST


Replace all sprintf() calls with sysfs_emit() in sysfs show functions.
sysfs_emit() is preferred over sprintf() for formatting sysfs output
as it provides better bounds checking and prevents potential buffer
overflows.

Signed-off-by: Sumeet Pawnikar <sumeet4linux@xxxxxxxxx>
---
drivers/acpi/device_sysfs.c | 20 ++++++++++----------
drivers/acpi/sysfs.c | 30 +++++++++++++++---------------
2 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
index cd199fbe4dc9..a52dc35ff9ba 100644
--- a/drivers/acpi/device_sysfs.c
+++ b/drivers/acpi/device_sysfs.c
@@ -27,7 +27,7 @@ static ssize_t acpi_object_path(acpi_handle handle, char *buf)
if (result)
return result;

- result = sprintf(buf, "%s\n", (char *)path.pointer);
+ result = sysfs_emit(buf, "%s\n", (char *)path.pointer);
kfree(path.pointer);
return result;
}
@@ -347,7 +347,7 @@ static ssize_t real_power_state_show(struct device *dev,
if (ret)
return ret;

- return sprintf(buf, "%s\n", acpi_power_state_string(state));
+ return sysfs_emit(buf, "%s\n", acpi_power_state_string(state));
}

static DEVICE_ATTR_RO(real_power_state);
@@ -357,7 +357,7 @@ static ssize_t power_state_show(struct device *dev,
{
struct acpi_device *adev = to_acpi_device(dev);

- return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
+ return sysfs_emit(buf, "%s\n", acpi_power_state_string(adev->power.state));
}

static DEVICE_ATTR_RO(power_state);
@@ -399,7 +399,7 @@ hid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);

- return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
+ return sysfs_emit(buf, "%s\n", acpi_device_hid(acpi_dev));
}
static DEVICE_ATTR_RO(hid);

@@ -408,7 +408,7 @@ static ssize_t uid_show(struct device *dev,
{
struct acpi_device *acpi_dev = to_acpi_device(dev);

- return sprintf(buf, "%s\n", acpi_device_uid(acpi_dev));
+ return sysfs_emit(buf, "%s\n", acpi_device_uid(acpi_dev));
}
static DEVICE_ATTR_RO(uid);

@@ -418,9 +418,9 @@ static ssize_t adr_show(struct device *dev,
struct acpi_device *acpi_dev = to_acpi_device(dev);

if (acpi_dev->pnp.bus_address > U32_MAX)
- return sprintf(buf, "0x%016llx\n", acpi_dev->pnp.bus_address);
+ return sysfs_emit(buf, "0x%016llx\n", acpi_dev->pnp.bus_address);
else
- return sprintf(buf, "0x%08llx\n", acpi_dev->pnp.bus_address);
+ return sysfs_emit(buf, "0x%08llx\n", acpi_dev->pnp.bus_address);
}
static DEVICE_ATTR_RO(adr);

@@ -482,7 +482,7 @@ sun_show(struct device *dev, struct device_attribute *attr,
if (ACPI_FAILURE(status))
return -EIO;

- return sprintf(buf, "%llu\n", sun);
+ return sysfs_emit(buf, "%llu\n", sun);
}
static DEVICE_ATTR_RO(sun);

@@ -498,7 +498,7 @@ hrv_show(struct device *dev, struct device_attribute *attr,
if (ACPI_FAILURE(status))
return -EIO;

- return sprintf(buf, "%llu\n", hrv);
+ return sysfs_emit(buf, "%llu\n", hrv);
}
static DEVICE_ATTR_RO(hrv);

@@ -513,7 +513,7 @@ static ssize_t status_show(struct device *dev, struct device_attribute *attr,
if (ACPI_FAILURE(status))
return -EIO;

- return sprintf(buf, "%llu\n", sta);
+ return sysfs_emit(buf, "%llu\n", sta);
}
static DEVICE_ATTR_RO(status);

diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
index e596224302f4..1bd2f555e673 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -687,7 +687,7 @@ static ssize_t counter_show(struct kobject *kobj,
acpi_irq_not_handled;
all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE].count =
acpi_gpe_count;
- size = sprintf(buf, "%8u", all_counters[index].count);
+ size = sysfs_emit(buf, "%8u", all_counters[index].count);

/* "gpe_all" or "sci" */
if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
@@ -698,29 +698,29 @@ static ssize_t counter_show(struct kobject *kobj,
goto end;

if (status & ACPI_EVENT_FLAG_ENABLE_SET)
- size += sprintf(buf + size, " EN");
+ size += sysfs_emit_at(buf, size, " EN");
else
- size += sprintf(buf + size, " ");
+ size += sysfs_emit_at(buf, size, " ");
if (status & ACPI_EVENT_FLAG_STATUS_SET)
- size += sprintf(buf + size, " STS");
+ size += sysfs_emit_at(buf, size, " STS");
else
- size += sprintf(buf + size, " ");
+ size += sysfs_emit_at(buf, size, " ");

if (!(status & ACPI_EVENT_FLAG_HAS_HANDLER))
- size += sprintf(buf + size, " invalid ");
+ size += sysfs_emit_at(buf, size, " invalid ");
else if (status & ACPI_EVENT_FLAG_ENABLED)
- size += sprintf(buf + size, " enabled ");
+ size += sysfs_emit_at(buf, size, " enabled ");
else if (status & ACPI_EVENT_FLAG_WAKE_ENABLED)
- size += sprintf(buf + size, " wake_enabled");
+ size += sysfs_emit_at(buf, size, " wake_enabled");
else
- size += sprintf(buf + size, " disabled ");
+ size += sysfs_emit_at(buf, size, " disabled ");
if (status & ACPI_EVENT_FLAG_MASKED)
- size += sprintf(buf + size, " masked ");
+ size += sysfs_emit_at(buf, size, " masked ");
else
- size += sprintf(buf + size, " unmasked");
+ size += sysfs_emit_at(buf, size, " unmasked");

end:
- size += sprintf(buf + size, "\n");
+ size += sysfs_emit_at(buf, size, "\n");
return result ? result : size;
}

@@ -937,7 +937,7 @@ static void __exit interrupt_stats_exit(void)

static ssize_t pm_profile_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
- return sprintf(buf, "%d\n", acpi_gbl_FADT.preferred_profile);
+ return sysfs_emit(buf, "%d\n", acpi_gbl_FADT.preferred_profile);
}

static const struct kobj_attribute pm_profile_attr = __ATTR_RO(pm_profile);
@@ -946,7 +946,7 @@ static ssize_t enabled_show(struct kobject *kobj, struct kobj_attribute *attr, c
{
struct acpi_hotplug_profile *hotplug = to_acpi_hotplug_profile(kobj);

- return sprintf(buf, "%d\n", hotplug->enabled);
+ return sysfs_emit(buf, "%d\n", hotplug->enabled);
}

static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr,
@@ -1000,7 +1000,7 @@ void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug,
static ssize_t force_remove_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
- return sprintf(buf, "%d\n", 0);
+ return sysfs_emit(buf, "%d\n", 0);
}

static ssize_t force_remove_store(struct kobject *kobj,
--
2.43.0