dm raid: fix parse_raid_params() variable range issue

parse_raid_params() compares variable "int value" with INT_MAX.

E.g. related Coverity report excerpt:
   CID 1364818 (#2 of 3): Operands don't affect result (CONSTANT_EXPRESSION_RESULT) [select issue]
1433                        if (value > INT_MAX) {

Fix by changing checks to avoid INT_MAX.

Whilst on it, avoid unnecessary checks against constants
and add check for sane recovery speed min/max.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 598c9e3e41a5..6f823f44b4aa 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -1370,19 +1370,18 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
                          * In device-mapper, we specify things in sectors, but
                          * MD records this value in kB
                          */
-                        value /= 2;
-                        if (value > COUNTER_MAX) {
+                        if (value < 0 || value / 2 > COUNTER_MAX) {
                                 rs->ti->error = "Max write-behind limit out of range";
                                 return -EINVAL;
                         }
 
-                        rs->md.bitmap_info.max_write_behind = value;
+                        rs->md.bitmap_info.max_write_behind = value / 2;
                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
                         if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
                                 rs->ti->error = "Only one daemon_sleep argument pair allowed";
                                 return -EINVAL;
                         }
-                        if (!value || (value > MAX_SCHEDULE_TIMEOUT)) {
+                        if (value < 0) {
                                 rs->ti->error = "daemon sleep period out of range";
                                 return -EINVAL;
                         }
@@ -1424,27 +1423,33 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
                                 return -EINVAL;
                         }
 
+                        if (value < 0) {
+                                rs->ti->error = "Bogus stripe cache entries value";
+                                return -EINVAL;
+                        }
                         rs->stripe_cache_entries = value;
                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
                         if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
                                 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
                                 return -EINVAL;
                         }
-                        if (value > INT_MAX) {
+
+                        if (value < 0) {
                                 rs->ti->error = "min_recovery_rate out of range";
                                 return -EINVAL;
                         }
-                        rs->md.sync_speed_min = (int)value;
+                        rs->md.sync_speed_min = value;
                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
                         if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
                                 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
                                 return -EINVAL;
                         }
-                        if (value > INT_MAX) {
+
+                        if (value < 0) {
                                 rs->ti->error = "max_recovery_rate out of range";
                                 return -EINVAL;
                         }
-                        rs->md.sync_speed_max = (int)value;
+                        rs->md.sync_speed_max = value;
                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
                         if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
                                 rs->ti->error = "Only one region_size argument pair allowed";
@@ -1490,6 +1495,12 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
                 return -EINVAL;
         }
 
+        if (rs->md.sync_speed_max &&
+            rs->md.sync_speed_min > rs->md.sync_speed_max) {
+                rs->ti->error = "Bogus recovery rates";
+                return -EINVAL;
+        }
+
         if (validate_region_size(rs, region_size))
                 return -EINVAL;