2019-04-26 20:11:23

by Helen Koike

[permalink] [raw]
Subject: [PATCH] dm: init: fix max devices/targets checks

dm-init should allow up to DM_MAX_{DEVICES,TARGETS} for devices/targets,
and not DM_MAX_{DEVICES,TARGETS} - 1.

Fix the checks and also fix the error message when the number of devices
is surpassed.

Signed-off-by: Helen Koike <[email protected]>

---
Hi,

This patch was tested by manipulating DM_MAX_TARGETS and DM_MAX_DEVICES
macros and making sure the test cases in the following test script[1] was
passing or failing when they should.

[1] https://gitlab.collabora.com/koike/dm-cmdline-test

Thanks
Helen

drivers/md/dm-init.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/md/dm-init.c b/drivers/md/dm-init.c
index 4b76f84424c3..352e803f566e 100644
--- a/drivers/md/dm-init.c
+++ b/drivers/md/dm-init.c
@@ -160,7 +160,7 @@ static int __init dm_parse_table(struct dm_device *dev, char *str)

while (table_entry) {
DMDEBUG("parsing table \"%s\"", str);
- if (++dev->dmi.target_count >= DM_MAX_TARGETS) {
+ if (++dev->dmi.target_count > DM_MAX_TARGETS) {
DMERR("too many targets %u > %d",
dev->dmi.target_count, DM_MAX_TARGETS);
return -EINVAL;
@@ -242,9 +242,9 @@ static int __init dm_parse_devices(struct list_head *devices, char *str)
return -ENOMEM;
list_add_tail(&dev->list, devices);

- if (++ndev >= DM_MAX_DEVICES) {
- DMERR("too many targets %u > %d",
- dev->dmi.target_count, DM_MAX_TARGETS);
+ if (++ndev > DM_MAX_DEVICES) {
+ DMERR("too many devices %lu > %d",
+ ndev, DM_MAX_DEVICES);
return -EINVAL;
}

--
2.20.1