From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit 1bb30b20b49773369c299d4d6c65227201328663 ]
After printing the list of thermal governors, then this function prints a newline character. The problem is that "size" has not been updated after printing the last governor. This means that it can write one character (the NUL terminator) beyond the end of the buffer.
Get rid of the "size" variable and just use "PAGE_SIZE - count" directly.
Fixes: 1b4f48494eb2 ("thermal: core: group functions related to governor handling") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Daniel Lezcano daniel.lezcano@linaro.org Link: https://lore.kernel.org/r/20210916131342.GB25094@kili Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/thermal/thermal_core.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index e669f83faa3c..17de8a9b991e 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -224,15 +224,14 @@ int thermal_build_list_of_policies(char *buf) { struct thermal_governor *pos; ssize_t count = 0; - ssize_t size = PAGE_SIZE;
mutex_lock(&thermal_governor_lock);
list_for_each_entry(pos, &thermal_governor_list, governor_list) { - size = PAGE_SIZE - count; - count += scnprintf(buf + count, size, "%s ", pos->name); + count += scnprintf(buf + count, PAGE_SIZE - count, "%s ", + pos->name); } - count += scnprintf(buf + count, size, "\n"); + count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
mutex_unlock(&thermal_governor_lock);