From 07301df7d2fc220d3de5f7ad804dcb941400cb00 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 28 May 2019 16:21:54 +0800 Subject: [PATCH] btrfs: trim: Check the range passed into to prevent overflow Normally the range->len is set to default value (U64_MAX), but when it's not default value, we should check if the range overflows. And if it overflows, return -EINVAL before doing anything. Reviewed-by: Nikolay Borisov Reviewed-by: Anand Jain Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/extent-tree.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 25b2c9d7fa7f..8b7eb22d508a 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -8966,6 +8966,7 @@ int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range) struct btrfs_device *device; struct list_head *devices; u64 group_trimmed; + u64 range_end = U64_MAX; u64 start; u64 end; u64 trimmed = 0; @@ -8975,16 +8976,23 @@ int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range) int dev_ret = 0; int ret = 0; + /* + * Check range overflow if range->len is set. + * The default range->len is U64_MAX. + */ + if (range->len != U64_MAX && + check_add_overflow(range->start, range->len, &range_end)) + return -EINVAL; + cache = btrfs_lookup_first_block_group(fs_info, range->start); for (; cache; cache = next_block_group(cache)) { - if (cache->key.objectid >= (range->start + range->len)) { + if (cache->key.objectid >= range_end) { btrfs_put_block_group(cache); break; } start = max(range->start, cache->key.objectid); - end = min(range->start + range->len, - cache->key.objectid + cache->key.offset); + end = min(range_end, cache->key.objectid + cache->key.offset); if (end - start >= range->minlen) { if (!block_group_cache_done(cache)) { -- 2.11.0