From c09abff87f90c81d74b6483837a665f97448a475 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Thu, 13 Jul 2017 18:10:07 +0200 Subject: [PATCH] btrfs: cloned bios must not be iterated by bio_for_each_segment_all We've started using cloned bios more in 4.13, there are some specifics regarding the iteration. Filipe found [1] that the raid56 iterated a cloned bio using bio_for_each_segment_all, which is incorrect. The cloned bios have wrong bi_vcnt and this could lead to silent corruptions. This patch adds assertions to all remaining bio_for_each_segment_all cases. [1] https://patchwork.kernel.org/patch/9838535/ Reviewed-by: Liu Bo Signed-off-by: David Sterba --- fs/btrfs/compression.c | 1 + fs/btrfs/disk-io.c | 1 + fs/btrfs/extent_io.c | 3 +++ fs/btrfs/inode.c | 2 ++ 4 files changed, 7 insertions(+) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index fcd323eceb5b..8ba1b86c9b72 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -152,6 +152,7 @@ csum_failed: * we have verified the checksum already, set page * checked so the end_io handlers know about it */ + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, cb->orig_bio, i) SetPageChecked(bvec->bv_page); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index b6758892874f..075beedb4352 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -964,6 +964,7 @@ static int btree_csum_one_bio(struct bio *bio) struct btrfs_root *root; int i, ret = 0; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { root = BTRFS_I(bvec->bv_page->mapping->host)->root; ret = csum_dirty_buffer(root->fs_info, bvec->bv_page); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 2e6f69908303..a3122fba54e8 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2452,6 +2452,7 @@ static void end_bio_extent_writepage(struct bio *bio) u64 end; int i; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { struct page *page = bvec->bv_page; struct inode *inode = page->mapping->host; @@ -2522,6 +2523,7 @@ static void end_bio_extent_readpage(struct bio *bio) int ret; int i; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { struct page *page = bvec->bv_page; struct inode *inode = page->mapping->host; @@ -3675,6 +3677,7 @@ static void end_bio_extent_buffer_writepage(struct bio *bio) struct extent_buffer *eb; int i, done; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { struct page *page = bvec->bv_page; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5d3c6ac960fd..529437c337b4 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8060,6 +8060,7 @@ static void btrfs_retry_endio_nocsum(struct bio *bio) ASSERT(bio->bi_io_vec->bv_len == btrfs_inode_sectorsize(inode)); done->uptodate = 1; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree, io_tree, done->start, bvec->bv_page, @@ -8151,6 +8152,7 @@ static void btrfs_retry_endio(struct bio *bio) io_tree = &BTRFS_I(inode)->io_tree; failure_tree = &BTRFS_I(inode)->io_failure_tree; + ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, i) { ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page, bvec->bv_offset, done->start, -- 2.39.2