[PATCH] md: Fix several raid1 bugs which cause a memory leak

- wrong test for 'is this a BARRIER bio'
- not freeing on all possible paths.
- using r1_bio after freeing it.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index d39f584cd8b3..5d88329e3c7a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -306,6 +306,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int
         r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
         int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
         conf_t *conf = mddev_to_conf(r1_bio->mddev);
+        struct bio *to_put = NULL;
 
         if (bio->bi_size)
                 return 1;
@@ -323,6 +324,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int
                  * this branch is our 'one mirror IO has finished' event handler:
                  */
                 r1_bio->bios[mirror] = NULL;
+                to_put = bio;
                 if (!uptodate) {
                         md_error(r1_bio->mddev, conf->mirrors[mirror].rdev);
                         /* an I/O failed, we can't clear the bitmap */
@@ -375,7 +377,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int
                         /* Don't dec_pending yet, we want to hold
                          * the reference over the retry
                          */
-                        return 0;
+                        goto out;
                 }
                 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
                         /* free extra copy of the data pages */
@@ -392,10 +394,11 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int
                 raid_end_bio_io(r1_bio);
         }
 
-        if (r1_bio->bios[mirror]==NULL)
-                bio_put(bio);
-
         rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
+ out:
+        if (to_put)
+                bio_put(to_put);
+
         return 0;
 }
 
@@ -857,7 +860,7 @@ static int make_request(request_queue_t *q, struct bio * bio)
         atomic_set(&r1_bio->remaining, 0);
         atomic_set(&r1_bio->behind_remaining, 0);
 
-        do_barriers = bio->bi_rw & BIO_RW_BARRIER;
+        do_barriers = bio_barrier(bio);
         if (do_barriers)
                 set_bit(R1BIO_Barrier, &r1_bio->state);