lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 27 May 2015 12:25:26 +0200
From:	Lukas Czerner <>
Cc:	Lukas Czerner <>
Subject: [PATCH] ext4: Try to initialize all groups we can in case of failure on ppc64

Currently on the machines with page size > block size when initializing
block group buddy cache we initialize it for all the block group bitmaps
in the page. However in the case of read error, checksum error, or if
a single bitmap is in any way corrupted we would fail to initialize all
of the bitmaps. This is problematic because we will not have access to
the other allocation groups even though those might be perfectly fine
and usable.

Fix this by reading all the bitmaps instead of error out on the first
problem and simply skip the bitmaps which were either not read properly,
or are not valid.

Signed-off-by: Lukas Czerner <>
 fs/ext4/mballoc.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 8d1e602..7e28007 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -882,10 +882,8 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
 	/* wait for I/O completion */
 	for (i = 0, group = first_group; i < groups_per_page; i++, group++) {
-		if (bh[i] && ext4_wait_block_bitmap(sb, group, bh[i])) {
+		if (bh[i] && ext4_wait_block_bitmap(sb, group, bh[i]))
 			err = -EIO;
-			goto out;
-		}
 	first_block = page->index * blocks_per_page;
@@ -898,6 +896,13 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
 			/* skip initialized uptodate buddy */
+		if (!buffer_verified(bh[group - first_group]) ||
+		    !buffer_uptodate(bh[group - first_group]))
+			/* Skip faulty bitmaps */
+			continue;
+		else
+			err = 0;
 		 * data carry information regarding this
 		 * particular group in the format specified

To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists