From: Dan Williams <dan.j.williams@intel.com>
Date: Wed, 26 May 2010 20:33:43 +0000 (-0700)
Subject: imsm: robustify recovery-start detection
X-Git-Tag: mdadm-3.1.3~45^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4363fd80bcc9f85ed824228dee5e6350a8d73e18;p=thirdparty%2Fmdadm.git

imsm: robustify recovery-start detection

update_recovery_start() assumed that the out-of-sync disk would always be
marked as IMSM_ORD_REBUILD in the disk_ord_tbl, but the segmentation
fault reported by Andy proves otherwise.  This might also be explained by
an interrupted rebuild and the disk has not yet been marked missing.

https://bugzilla.redhat.com/show_bug.cgi?id=592030

Reported-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---

diff --git a/super-intel.c b/super-intel.c
index bdd7a968..dd9699de 100644
--- a/super-intel.c
+++ b/super-intel.c
@@ -4044,6 +4044,15 @@ static void update_recovery_start(struct imsm_dev *dev, struct mdinfo *array)
 			rebuild = d;
 		}
 
+	if (!rebuild) {
+		/* (?) none of the disks are marked with
+		 * IMSM_ORD_REBUILD, so assume they are missing and the
+		 * disk_ord_tbl was not correctly updated
+		 */
+		dprintf("%s: failed to locate out-of-sync disk\n", __func__);
+		return;
+	}
+
 	units = __le32_to_cpu(dev->vol.curr_migr_unit);
 	rebuild->recovery_start = units * blocks_per_migr_unit(dev);
 }