block: sanitize the elevator name before passing it to __elevator_change

The stripped name should also be used for the none check.  To do so
strip it in the caller and pass in the sanitized name.  Drop the pointless
__ prefix in the function name while we're at it.

Based on a patch from Jinlong Chen <nickyc975@zju.edu.cn>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2022-10-20 08:48:17 +02:00 committed by Jens Axboe
parent dd6f7f17bf
commit 58367c8a5f

View File

@ -734,9 +734,8 @@ int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
/*
* Switch this queue to the given IO scheduler.
*/
static int __elevator_change(struct request_queue *q, const char *name)
static int elevator_change(struct request_queue *q, const char *elevator_name)
{
char elevator_name[ELV_NAME_MAX];
struct elevator_type *e;
/* Make sure queue is not in the middle of being removed */
@ -746,14 +745,13 @@ static int __elevator_change(struct request_queue *q, const char *name)
/*
* Special case for mq, turn off scheduling
*/
if (!strncmp(name, "none", 4)) {
if (!strncmp(elevator_name, "none", 4)) {
if (!q->elevator)
return 0;
return elevator_switch(q, NULL);
}
strlcpy(elevator_name, name, sizeof(elevator_name));
e = elevator_get(q, strstrip(elevator_name), true);
e = elevator_get(q, elevator_name, true);
if (!e)
return -EINVAL;
@ -766,18 +764,19 @@ static int __elevator_change(struct request_queue *q, const char *name)
return elevator_switch(q, e);
}
ssize_t elv_iosched_store(struct request_queue *q, const char *name,
ssize_t elv_iosched_store(struct request_queue *q, const char *buf,
size_t count)
{
char elevator_name[ELV_NAME_MAX];
int ret;
if (!elv_support_iosched(q))
return count;
ret = __elevator_change(q, name);
strlcpy(elevator_name, buf, sizeof(elevator_name));
ret = elevator_change(q, strstrip(elevator_name));
if (!ret)
return count;
return ret;
}