ceph: fix decoding of pool snap info

The pool info contains a vector for snap_info_t, not snap ids.  This fixes
the broken decoding, which would declare teh update corrupt when a pool
snapshot was created.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 26 insertions, 4 deletions

diff --git a/fs/ceph/osdmap.c b/fs/ceph/osdmap.c
index 1d5f58cc2d93..e94c6fb2e2a4 100644
--- a/fs/ceph/osdmap.c
+++ b/fs/ceph/osdmap.c
@@ -424,12 +424,30 @@ static void __remove_pg_pool(struct rb_root *root, struct ceph_pg_pool_info *pi)
         kfree(pi);
 }
 
-static void __decode_pool(void **p, struct ceph_pg_pool_info *pi)
+static int __decode_pool(void **p, void *end, struct ceph_pg_pool_info *pi)
 {
+        unsigned n, m;
+
         ceph_decode_copy(p, &pi->v, sizeof(pi->v));
         calc_pg_masks(pi);
-        *p += le32_to_cpu(pi->v.num_snaps) * sizeof(u64);
+
+        /* num_snaps * snap_info_t */
+        n = le32_to_cpu(pi->v.num_snaps);
+        while (n--) {
+                ceph_decode_need(p, end, sizeof(u64) + 1 + sizeof(u64) +
+                                 sizeof(struct ceph_timespec), bad);
+                *p += sizeof(u64) +       /* key */
+                        1 + sizeof(u64) + /* u8, snapid */
+                        sizeof(struct ceph_timespec);
+                m = ceph_decode_32(p);    /* snap name */
+                *p += m;
+        }
+
         *p += le32_to_cpu(pi->v.num_removed_snap_intervals) * sizeof(u64) * 2;
+        return 0;
+
+bad:
+        return -EINVAL;
 }
 
 static int __decode_pool_names(void **p, void *end, struct ceph_osdmap *map)
@@ -571,7 +589,9 @@ struct ceph_osdmap *osdmap_decode(void **p, void *end)
                         kfree(pi);
                         goto bad;
                 }
-                __decode_pool(p, pi);
+                err = __decode_pool(p, end, pi);
+                if (err < 0)
+                        goto bad;
                 __insert_pg_pool(&map->pg_pools, pi);
         }
 
@@ -760,7 +780,9 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
                         pi->id = pool;
                         __insert_pg_pool(&map->pg_pools, pi);
                 }
-                __decode_pool(p, pi);
+                err = __decode_pool(p, end, pi);
+                if (err < 0)
+                        goto bad;
         }
         if (version >= 5 && __decode_pool_names(p, end, map) < 0)
                 goto bad;