summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJoe Thornber <ejt@redhat.com>2021-12-10 13:44:13 +0000
committerMike Snitzer <snitzer@redhat.com>2022-01-04 13:56:03 -0500
commit85bca3c05b6cca31625437eedf2060e846c4bbad (patch)
tree14d1f97999ed6e45c2c4fe71aab6fa2f421bd395
parentc671ffa55d8b0dd3ed0a329e15dfe9c58f7483cd (diff)
downloadlinux-85bca3c05b6cca31625437eedf2060e846c4bbad.tar.bz2
dm btree: add a defensive bounds check to insert_at()
Corrupt metadata could trigger an out of bounds write. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
-rw-r--r--drivers/md/persistent-data/dm-btree.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index 0703ca7a7d9a..5ce64e93aae7 100644
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -81,14 +81,16 @@ void inc_children(struct dm_transaction_manager *tm, struct btree_node *n,
}
static int insert_at(size_t value_size, struct btree_node *node, unsigned index,
- uint64_t key, void *value)
- __dm_written_to_disk(value)
+ uint64_t key, void *value)
+ __dm_written_to_disk(value)
{
uint32_t nr_entries = le32_to_cpu(node->header.nr_entries);
+ uint32_t max_entries = le32_to_cpu(node->header.max_entries);
__le64 key_le = cpu_to_le64(key);
if (index > nr_entries ||
- index >= le32_to_cpu(node->header.max_entries)) {
+ index >= max_entries ||
+ nr_entries >= max_entries) {
DMERR("too many entries in btree node for insert");
__dm_unbless_for_disk(value);
return -ENOMEM;