Check all member devices in enough_fd

The loop over all member devices in enough_fd could easily stop
before it had found all devices.  This would cause --re-add to
fail incorrectly.

So change the loop to be based on the reported number of devices
in the device - with a safe-guard limit of 1024.

Change some other loops to be more careful too.

Reported-by: "Schmidt, Annemarie" <Annemarie.Schmidt@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>

3 files changed, 24 insertions, 7 deletions

diff --git a/Manage.c b/Manage.c
index 0e54bc7..66d6978 100644
--- a/Manage.c
+++ b/Manage.c
@@ -438,19 +438,21 @@ int Manage_subdevs(char *devname, int fd,
 
 		if (strcmp(dv->devname, "failed")==0 ||
 		    strcmp(dv->devname, "faulty")==0) {
+			int remaining_disks = array.nr_disks;
 			if (dv->disposition != 'r') {
 				fprintf(stderr, Name ": %s only meaningful "
 					"with -r, not -%c\n",
 					dv->devname, dv->disposition);
 				return 1;
 			}
-			for (; j < array.raid_disks + array.nr_disks ; j++) {
+			for (; j < 1024 && remaining_disks > 0; j++) {
 				unsigned dev;
 				disc.number = j;
 				if (ioctl(fd, GET_DISK_INFO, &disc))
 					continue;
 				if (disc.major == 0 && disc.minor == 0)
 					continue;
+				remaining_disks --;
 				if ((disc.state & 1) == 0) /* faulty */
 					continue;
 				dev = makedev(disc.major, disc.minor);
@@ -469,13 +471,14 @@ int Manage_subdevs(char *devname, int fd,
 			if (next != dv)
 				continue;
 		} else if (strcmp(dv->devname, "detached") == 0) {
+			int remaining_disks = array.nr_disks;
 			if (dv->disposition != 'r' && dv->disposition != 'f') {
 				fprintf(stderr, Name ": %s only meaningful "
 					"with -r of -f, not -%c\n",
 					dv->devname, dv->disposition);
 				return 1;
 			}
-			for (; j < array.raid_disks + array.nr_disks; j++) {
+			for (; j < 1024 && remaining_disks > 0; j++) {
 				int sfd;
 				unsigned dev;
 				disc.number = j;
@@ -483,6 +486,7 @@ int Manage_subdevs(char *devname, int fd,
 					continue;
 				if (disc.major == 0 && disc.minor == 0)
 					continue;
+				remaining_disks --;
 				sprintf(dvname,"%d:%d", disc.major, disc.minor);
 				sfd = dev_open(dvname, O_RDONLY);
 				if (sfd >= 0) {
diff --git a/Monitor.c b/Monitor.c
index 55aebeb..101bca4 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -449,6 +449,8 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 	char *dev = st->devname;
 	int fd;
 	int i;
+	int remaining_disks;
+	int last_disk;
 
 	if (test)
 		alert("TestMessage", dev, NULL, ainfo);
@@ -565,7 +567,8 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 	}
 	st->percent = mse->percent;
 
-	for (i=0; i<MaxDisks && i <= array.raid_disks + array.nr_disks;
+	remaining_disks = array.nr_disks;
+	for (i=0; i<MaxDisks && remaining_disks > 0;
 	     i++) {
 		mdu_disk_info_t disc;
 		disc.number = i;
@@ -573,9 +576,12 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 			info[i].state = disc.state;
 			info[i].major = disc.major;
 			info[i].minor = disc.minor;
+			if (disc.major || disc.minor)
+				remaining_disks --;
 		} else
 			info[i].major = info[i].minor = 0;
 	}
+	last_disk = i;
 
 	if (mse->metadata_version &&
 	    strncmp(mse->metadata_version, "external:", 9) == 0 &&
@@ -596,7 +602,7 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 		int change;
 		char *dv = NULL;
 		disc.number = i;
-		if (i > array.raid_disks + array.nr_disks) {
+		if (i >= last_disk) {
 			newstate = 0;
 			disc.major = disc.minor = 0;
 		} else if (info[i].major || info[i].minor) {
diff --git a/util.c b/util.c
index 1056ae4..e92be4f 100644
--- a/util.c
+++ b/util.c
@@ -370,10 +370,14 @@ int enough_fd(int fd)
 	    array.raid_disks <= 0)
 		return 0;
 	avail = calloc(array.raid_disks, 1);
-	for (i=0; i<array.raid_disks + array.nr_disks; i++) {
+	for (i=0; i < 1024 && array.nr_disks > 0; i++) {
 		disk.number = i;
 		if (ioctl(fd, GET_DISK_INFO, &disk) != 0)
 			continue;
+		if (disk.major == 0 && disk.minor == 0)
+			continue;
+		array.nr_disks--;
+
 		if (! (disk.state & (1<<MD_DISK_SYNC)))
 			continue;
 		if (disk.raid_disk < 0 || disk.raid_disk >= array.raid_disks)
@@ -1256,10 +1260,13 @@ int check_partitions(int fd, char *dname, unsigned long long freesize,
 void get_one_disk(int mdfd, mdu_array_info_t *ainf, mdu_disk_info_t *disk)
 {
 	int d;
+
 	ioctl(mdfd, GET_ARRAY_INFO, ainf);
-	for (d = 0 ; d < ainf->raid_disks + ainf->nr_disks ; d++)
-		if (ioctl(mdfd, GET_DISK_INFO, disk) == 0)
+	for (d = 0 ; d < 1024 ; d++) {
+		if (ioctl(mdfd, GET_DISK_INFO, disk) == 0 &&
+		    (disk->major || disk->minor))
 			return;
+	}
 }
 
 int open_container(int fd)