From: Brian Behlendorf <behlendorf1@llnl.gov>
Date: Tue, 7 Jan 2014 22:24:37 +0000 (+0100)
Subject: Fix nvlist 'Bus Error' for Sparc
X-Git-Tag: zfs-0.6.3~121
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=aa0218d6a12814fac50b287214f9f3b0b99e11b1;p=zfs

Fix nvlist 'Bus Error' for Sparc

The mis-aligned memory accesses in nvpair_native_embedded() and
nvpair_native_embedded_array() will cause a 'Bus Error' for
architectures such as Sparc which not fully byte addressible.
To avoid this issue care is taken to avoid dereferencing the
potentially mis-aligned packed nvlist_t.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: marku89 <mar42@kola.li>
Issue #1700
---

diff --git a/module/nvpair/nvpair.c b/module/nvpair/nvpair.c
index 550356c58..f5c31663a 100644
--- a/module/nvpair/nvpair.c
+++ b/module/nvpair/nvpair.c
@@ -2580,7 +2580,8 @@ nvpair_native_embedded(nvstream_t *nvs, nvpair_t *nvp)
 		 * structure. The address may not be aligned, so we have
 		 * to use bzero.
 		 */
-		bzero(&packed->nvl_priv, sizeof (packed->nvl_priv));
+		bzero((char *)packed + offsetof(nvlist_t, nvl_priv),
+		    sizeof (uint64_t));
 	}
 
 	return (nvs_embedded(nvs, EMBEDDED_NVL(nvp)));
@@ -2608,7 +2609,8 @@ nvpair_native_embedded_array(nvstream_t *nvs, nvpair_t *nvp)
 			 * packed structure. The address may not be aligned,
 			 * so we have to use bzero.
 			 */
-			bzero(&packed->nvl_priv, sizeof (packed->nvl_priv));
+			bzero((char *)packed + offsetof(nvlist_t, nvl_priv),
+			    sizeof (uint64_t));
 	}
 
 	return (nvs_embedded_nvl_array(nvs, nvp, NULL));