2009-04-23 07:37:20

by Chris Wright

[permalink] [raw]
Subject: [patch 024/100] md/raid1 - dont assume newly allocated bvecs are initialised.

-stable review patch. If anyone has any objections, please let us know.
---------------------

From: NeilBrown <[email protected]>

upstream commit: 303a0e11d0ee136ad8f53f747f3c377daece763b

Since commit d3f761104b097738932afcc310fbbbbfb007ef92
newly allocated bvecs aren't initialised to NULL, so we have
to be more careful about freeing a bio which only managed
to get a few pages allocated to it. Otherwise the resync
process crashes.

This patch is appropriate for 2.6.29-stable.

Cc: [email protected]
Cc: "Jens Axboe" <[email protected]>
Reported-by: Gabriele Tozzi <[email protected]>
Signed-off-by: NeilBrown <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
drivers/md/raid1.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -120,6 +120,7 @@ static void * r1buf_pool_alloc(gfp_t gfp
goto out_free_pages;

bio->bi_io_vec[i].bv_page = page;
+ bio->bi_vcnt = i+1;
}
}
/* If not user-requests, copy the page pointers to all bios */
@@ -135,9 +136,9 @@ static void * r1buf_pool_alloc(gfp_t gfp
return r1_bio;

out_free_pages:
- for (i=0; i < RESYNC_PAGES ; i++)
- for (j=0 ; j < pi->raid_disks; j++)
- safe_put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
+ for (j=0 ; j < pi->raid_disks; j++)
+ for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++)
+ put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
j = -1;
out_free_bio:
while ( ++j < pi->raid_disks )