From 7f2d219e78e95a137a9c76fddac7ff8228260439 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 17 Jan 2024 11:02:26 +1030 Subject: btrfs: scrub: limit RST scrub to chunk boundary [BUG] If there is an extent beyond chunk boundary, currently RST scrub would error out. [CAUSE] In scrub_submit_extent_sector_read(), we completely rely on extent_sector_bitmap, which is populated using extent tree. The extent tree can be corrupted that there is an extent item beyond a chunk. In that case, RST scrub would fail and error out. [FIX] Despite the extent_sector_bitmap usage, also limit the read to chunk boundary. Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/scrub.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/btrfs') diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 2d81b1a18a04..0123d2728923 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -1646,6 +1646,9 @@ static void scrub_submit_extent_sector_read(struct scrub_ctx *sctx, { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct btrfs_bio *bbio = NULL; + unsigned int nr_sectors = min(BTRFS_STRIPE_LEN, stripe->bg->start + + stripe->bg->length - stripe->logical) >> + fs_info->sectorsize_bits; u64 stripe_len = BTRFS_STRIPE_LEN; int mirror = stripe->mirror_num; int i; @@ -1656,6 +1659,10 @@ static void scrub_submit_extent_sector_read(struct scrub_ctx *sctx, struct page *page = scrub_stripe_get_page(stripe, i); unsigned int pgoff = scrub_stripe_get_page_offset(stripe, i); + /* We're beyond the chunk boundary, no need to read anymore. */ + if (i >= nr_sectors) + break; + /* The current sector cannot be merged, submit the bio. */ if (bbio && ((i > 0 && -- cgit v1.2.3