Messages in this thread Patch in this message | | | From | Takashi Iwai <> | Subject | [PATCH] drivers/base/cpu: Use scnprintf() for avoiding potential buffer overflow | Date | Wed, 11 Mar 2020 08:12:00 +0100 |
| |
Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@suse.de> --- drivers/base/cpu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 6265871a4af2..0abcd9d68714 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -231,7 +231,7 @@ static struct cpu_attr cpu_attrs[] = { static ssize_t print_cpus_kernel_max(struct device *dev, struct device_attribute *attr, char *buf) { - int n = snprintf(buf, PAGE_SIZE-2, "%d\n", NR_CPUS - 1); + int n = scnprintf(buf, PAGE_SIZE-2, "%d\n", NR_CPUS - 1); return n; } static DEVICE_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL); @@ -258,13 +258,13 @@ static ssize_t print_cpus_offline(struct device *dev, buf[n++] = ','; if (nr_cpu_ids == total_cpus-1) - n += snprintf(&buf[n], len - n, "%u", nr_cpu_ids); + n += scnprintf(&buf[n], len - n, "%u", nr_cpu_ids); else - n += snprintf(&buf[n], len - n, "%u-%d", + n += scnprintf(&buf[n], len - n, "%u-%d", nr_cpu_ids, total_cpus-1); } - n += snprintf(&buf[n], len - n, "\n"); + n += scnprintf(&buf[n], len - n, "\n"); return n; } static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); -- 2.16.4
| |