Add _FORTIFY_SOURCE to mdadm.O2 build.

When building mdadm.O2, set _FORTIFY_SOURCE to get more
warnings, and also build mdmon.O2 to find warnings in that
code too.
Then fix the warnings.

Suggested-by: Luca Berra <bluca@comedia.it>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 29 insertions, 16 deletions

diff --git a/Grow.c b/Grow.c
index 4dfa344..d7d8472 100644
--- a/Grow.c
+++ b/Grow.c
@@ -1254,6 +1254,7 @@ int Grow_reshape(char *devname, int fd, int quiet, char *backup_file,
  * 
  */
 
+/* FIXME return status is never checked */
 int grow_backup(struct mdinfo *sra,
 		unsigned long long offset, /* per device */
 		unsigned long stripes, /* per device */
@@ -1336,16 +1337,16 @@ int grow_backup(struct mdinfo *sra,
 			bsb.sb_csum2 = bsb_csum((char*)&bsb,
 						((char*)&bsb.sb_csum2)-((char*)&bsb));
 
-		lseek64(destfd[i], destoffsets[i] - 4096, 0);
-		write(destfd[i], &bsb, 512);
+		rv |= lseek64(destfd[i], destoffsets[i] - 4096, 0);
+		rv = rv ?: write(destfd[i], &bsb, 512);
 		if (destoffsets[i] > 4096) {
-			lseek64(destfd[i], destoffsets[i]+stripes*chunk*odata, 0);
-			write(destfd[i], &bsb, 512);
+			rv |= lseek64(destfd[i], destoffsets[i]+stripes*chunk*odata, 0);
+			rv = rv ?: write(destfd[i], &bsb, 512);
 		}
 		fsync(destfd[i]);
 	}
 
-	return 0;
+	return rv;
 }
 
 /* in 2.6.30, the value reported by sync_completed can be
@@ -1358,6 +1359,7 @@ int grow_backup(struct mdinfo *sra,
  * The various caller give appropriate values so that
  * every works.
  */
+/* FIXME return value is often ignored */
 int wait_backup(struct mdinfo *sra,
 		unsigned long long offset, /* per device */
 		unsigned long long blocks, /* per device */
@@ -1371,6 +1373,7 @@ int wait_backup(struct mdinfo *sra,
 	int fd = sysfs_get_fd(sra, NULL, "sync_completed");
 	unsigned long long completed;
 	int i;
+	int rv;
 
 	if (fd < 0)
 		return -1;
@@ -1402,24 +1405,26 @@ int wait_backup(struct mdinfo *sra,
 		bsb.length = __cpu_to_le64(0);
 	}
 	bsb.mtime = __cpu_to_le64(time(0));
+	rv = 0;
 	for (i = 0; i < dests; i++) {
 		bsb.devstart = __cpu_to_le64(destoffsets[i]/512);
 		bsb.sb_csum = bsb_csum((char*)&bsb, ((char*)&bsb.sb_csum)-((char*)&bsb));
 		if (memcmp(bsb.magic, "md_backup_data-2", 16) == 0)
 			bsb.sb_csum2 = bsb_csum((char*)&bsb,
 						((char*)&bsb.sb_csum2)-((char*)&bsb));
-		lseek64(destfd[i], destoffsets[i]-4096, 0);
-		write(destfd[i], &bsb, 512);
+		rv |= lseek64(destfd[i], destoffsets[i]-4096, 0);
+		rv = rv ?: write(destfd[i], &bsb, 512);
 		fsync(destfd[i]);
 	}
-	return 0;
+	return rv;
 }
 
 static void fail(char *msg)
 {
-	write(2, msg, strlen(msg));
-	write(2, "\n", 1);
-	exit(1);
+	int rv;
+	rv = write(2, msg, strlen(msg));
+	rv |= write(2, "\n", 1);
+	exit(rv ? 1 : 2);
 }
 
 static char *abuf, *bbuf;
@@ -1455,8 +1460,12 @@ static void validate(int afd, int bfd, unsigned long long offset)
 			free(abuf);
 			free(bbuf);
 			abuflen = len;
-			posix_memalign((void**)&abuf, 4096, abuflen);
-			posix_memalign((void**)&bbuf, 4096, abuflen);
+			if (posix_memalign((void**)&abuf, 4096, abuflen) ||
+			    posix_memalign((void**)&bbuf, 4096, abuflen)) {
+				abuflen = 0;
+				/* just stop validating on mem-alloc failure */
+				return;
+			}
 		}
 
 		lseek64(bfd, offset, 0);
@@ -1511,7 +1520,9 @@ static int child_grow(int afd, struct mdinfo *sra, unsigned long stripes,
 	char *buf;
 	int degraded = 0;
 
-	posix_memalign((void**)&buf, 4096, disks * chunk);
+	if (posix_memalign((void**)&buf, 4096, disks * chunk))
+		/* Don't start the 'reshape' */
+		return 0;
 	sysfs_set_num(sra, NULL, "suspend_hi", 0);
 	sysfs_set_num(sra, NULL, "suspend_lo", 0);
 	grow_backup(sra, 0, stripes,
@@ -1539,7 +1550,8 @@ static int child_shrink(int afd, struct mdinfo *sra, unsigned long stripes,
 	int rv;
 	int degraded = 0;
 
-	posix_memalign((void**)&buf, 4096, disks * chunk);
+	if (posix_memalign((void**)&buf, 4096, disks * chunk))
+		return 0;
 	start = sra->component_size - stripes * chunk/512;
 	sysfs_set_num(sra, NULL, "sync_max", start);
 	sysfs_set_str(sra, NULL, "sync_action", "reshape");
@@ -1578,7 +1590,8 @@ static int child_same_size(int afd, struct mdinfo *sra, unsigned long stripes,
 	int degraded = 0;
 
 
-	posix_memalign((void**)&buf, 4096, disks * chunk);
+	if (posix_memalign((void**)&buf, 4096, disks * chunk))
+		return 0;
 
 	sysfs_set_num(sra, NULL, "suspend_lo", 0);
 	sysfs_set_num(sra, NULL, "suspend_hi", 0);