From f224a6915f266921507bb6e50a82f87a3de5b4b5 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Sun, 31 Jan 2016 14:35:59 +0100 Subject: crush: ensure bucket id is valid before indexing buckets array We were indexing the buckets array without verifying the index was within the [0,max_buckets) range. This could happen because a multistep rule does not have enough buckets and has CRUSH_ITEM_NONE for an intermediate result, which would feed in CRUSH_ITEM_NONE and make us crash. Reflects ceph.git commit 976a24a326da8931e689ee22fce35feab5b67b76. Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil --- net/ceph/crush/mapper.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'net/ceph') diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c index 393bfb22d5bb..97ecf6f262aa 100644 --- a/net/ceph/crush/mapper.c +++ b/net/ceph/crush/mapper.c @@ -888,6 +888,7 @@ int crush_do_rule(const struct crush_map *map, osize = 0; for (i = 0; i < wsize; i++) { + int bno; /* * see CRUSH_N, CRUSH_N_MINUS macros. * basically, numrep <= 0 means relative to @@ -900,6 +901,13 @@ int crush_do_rule(const struct crush_map *map, continue; } j = 0; + /* make sure bucket id is valid */ + bno = -1 - w[i]; + if (bno < 0 || bno >= map->max_buckets) { + /* w[i] is probably CRUSH_ITEM_NONE */ + dprintk(" bad w[i] %d\n", w[i]); + continue; + } if (firstn) { int recurse_tries; if (choose_leaf_tries) @@ -911,7 +919,7 @@ int crush_do_rule(const struct crush_map *map, recurse_tries = choose_tries; osize += crush_choose_firstn( map, - map->buckets[-1-w[i]], + map->buckets[bno], weight, weight_max, x, numrep, curstep->arg2, @@ -930,7 +938,7 @@ int crush_do_rule(const struct crush_map *map, numrep : (result_max-osize)); crush_choose_indep( map, - map->buckets[-1-w[i]], + map->buckets[bno], weight, weight_max, x, out_size, numrep, curstep->arg2, -- cgit v1.2.3-55-g7522