[PATCH] mm, vmpressure: Fix a signedness bug in vmpressure_register_event()

Dan Carpenter
2019-09-25T11:05:04Z

The "mode" and "level" variables are enums and in this context GCC will
treat them as unsigned ints so the error handling is never triggered.

I also removed the bogus initializer because it isn't required any more
and it's sort of confusing.

Fixes: 3cadfa2b9497 ("mm/vmpressure.c: convert to use match_string() helper")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
mm/vmpressure.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index f3b50811497a..fe077500cf20 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -362,7 +362,7 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
struct vmpressure *vmpr = memcg_to_vmpressure(memcg);
struct vmpressure_event *ev;
enum vmpressure_modes mode = VMPRESSURE_NO_PASSTHROUGH;
- enum vmpressure_levels level = -1;
+ enum vmpressure_levels level;
char *spec, *spec_orig;
char *token;
int ret = 0;
@@ -376,7 +376,7 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
/* Find required level */
token = strsep(&spec, ",");
level = match_string(vmpressure_str_levels, VMPRESSURE_NUM_LEVELS, token);
- if (level < 0) {
+ if ((int)level < 0) {
ret = level;
goto out;
}
@@ -385,7 +385,7 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
token = strsep(&spec, ",");
if (token) {
mode = match_string(vmpressure_str_modes, VMPRESSURE_NUM_MODES, token);
- if (mode < 0) {
+ if ((int)mode < 0) {
ret = mode;
goto out;
}
--
2.20.1