linux-kernel - [PATCH 08/19] drbd: fix spurious alert level printk

lists.openwall.net		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 linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1438693003-17554-9-git-send-email-philipp.reisner@linbit.com>
Date:	Tue,  4 Aug 2015 14:56:32 +0200
From:	Philipp Reisner <philipp.reisner@...bit.com>
To:	linux-kernel@...r.kernel.org, Jens Axboe <axboe@...nel.dk>
Cc:	drbd-dev@...ts.linbit.com
Subject: [PATCH 08/19] drbd: fix spurious alert level printk

From: Lars Ellenberg <lars.ellenberg@...bit.com>

When accessing out meta data area on disk, we double check the
plausibility of the requested sector offsets, and are very noisy about
it if they look suspicious.

During initial read of our "superblock", for "external" meta data,
this triggered because the range estimate returned by
drbd_md_last_sector() was still wrong.

Signed-off-by: Philipp Reisner <philipp.reisner@...bit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@...bit.com>
---
 drivers/block/drbd/drbd_main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 30c1120..903d22e 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -3271,6 +3271,10 @@ int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev)
 	 * and read it. */
 	bdev->md.meta_dev_idx = bdev->disk_conf->meta_dev_idx;
 	bdev->md.md_offset = drbd_md_ss(bdev);
+	/* Even for (flexible or indexed) external meta data,
+	 * initially restrict us to the 4k superblock for now.
+	 * Affects the paranoia out-of-range access check in drbd_md_sync_page_io(). */
+	bdev->md.md_size_sect = 8;
 
 	if (drbd_md_sync_page_io(device, bdev, bdev->md.md_offset, READ)) {
 		/* NOTE: can't do normal error processing here as this is
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/