o ioctl DIOCGDINFO error wasn't checked

o memory wasn't reclaimed in certain cases
o add more msgs under #ifdef DEBUG
o rewrite tangle of for loops for clarity

NB: Open_Disk should redo how it malloc's memory so the caller can free
    everything.  Documentation says the caller can free the disk list to
    reclaim everything but this leaks the indirect strings.  Fixing this
    is simple for the sysctl case but adds complexity to the fallback,
    non-sysctl, case.

1 files changed, 29 insertions, 7 deletions

diff --git a/lib/libdisk/disk.c b/lib/libdisk/disk.c
index 72bbe8a..d10ade3 100644
--- a/lib/libdisk/disk.c
+++ b/lib/libdisk/disk.c
@@ -92,7 +92,13 @@ Int_Open_Disk(const char *name, u_long size)
 	}
 
 	memset(&dl, 0, sizeof dl);
-	ioctl(fd, DIOCGDINFO, &dl);
+	if (ioctl(fd, DIOCGDINFO, &dl) < 0) {
+#ifdef DEBUG
+		warn("DIOCGDINFO(%s) failed", device);
+#endif
+		close(fd);
+		return 0;
+	}
 	i = ioctl(fd, DIOCGSLICEINFO, &ds);
 	if (i < 0) {
 #ifdef DEBUG
@@ -129,8 +135,13 @@ Int_Open_Disk(const char *name, u_long size)
 		}
 	}
 	free (buf);
-	if (sector_size > MAX_SEC_SIZE)
+	if (sector_size > MAX_SEC_SIZE) {
+#ifdef DEBUG
+		warn("Int_Open_Disk: could not determine sector size, "
+		     "calculated %u, max %u\n", sector_size, MAX_SEC_SIZE);
+#endif
 		return NULL; /* could not determine sector size */
+	}
 
 #ifdef PC98
 	p = (unsigned char*)read_block(fd, 1, sector_size);
@@ -508,20 +519,31 @@ Disk_Names()
     static char **disks;
     int error;
     size_t listsize;
-    char *disklist, **dp;
+    char *disklist;
 
     disks = malloc(sizeof *disks * (1 + MAX_NO_DISKS));
+    if (disks == NULL)
+	    return NULL;
     memset(disks,0,sizeof *disks * (1 + MAX_NO_DISKS));
     error = sysctlbyname("kern.disks", NULL, &listsize, NULL, 0);
     if (!error) {
 	    disklist = (char *)malloc(listsize);
+	    if (disklist == NULL) {
+		    free(disks);
+		    return NULL;
+	    }
 	    memset(disklist, 0, listsize);
 	    error = sysctlbyname("kern.disks", disklist, &listsize, NULL, 0);
-	    if (error) 
+	    if (error) {
+		    free(disklist);
+		    free(disks);
 		    return NULL;
-	    disk_cnt = 0;
-	    for (dp = disks; ((*dp = strsep(&disklist, " ")) != NULL) && 
-			 disk_cnt < MAX_NO_DISKS; disk_cnt++, dp++);
+	    }
+	    for (disk_cnt = 0; disk_cnt < MAX_NO_DISKS; disk_cnt++) {
+		    disks[disk_cnt] = strsep(&disklist, " ");
+		    if (disks[disk_cnt] == NULL)
+			    break;
+											    }
     } else {
     warn("kern.disks sysctl not available");
     disk_cnt = 0;