commit b6391ac73400eff38377a4a7364bd3df5efb5178 upstream.

Complete read error handling paths for all three kinds of compressed pages:

1) For cache-managed pages, PG_uptodate will be checked since read_endio will unlock and SetPageUptodate for these pages;

2) For inplaced pages, read_endio cannot SetPageUptodate directly since it should be used to mark the final decompressed data, PG_error will be set with page locked for IO error instead;

3) For staging pages, PG_error is used, which is similar to what we do for inplaced pages.

Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Cc: stable@vger.kernel.org # 4.19+ Reviewed-by: Chao Yu yuchao0@huawei.com Signed-off-by: Gao Xiang gaoxiang25@huawei.com --- This series resolves the following conflicts: FAILED: patch "[PATCH] staging: erofs: fix error handling when failed to read" failed to apply to 4.19-stable tree FAILED: patch "[PATCH] staging: erofs: keep corrupted fs from crashing kernel in" failed to apply to 4.19-stable tree

Thanks, Gao Xiang

drivers/staging/erofs/unzip_vle.c | 42 +++++++++++++++++++++---------- 1 file changed, 29 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index f44662dd795c..bb9a69158ba4 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -885,6 +885,7 @@ static int z_erofs_vle_unzip(struct super_block *sb, overlapped = false; compressed_pages = grp->compressed_pages;

+ err = 0; for (i = 0; i < clusterpages; ++i) { unsigned pagenr;

@@ -894,26 +895,39 @@ static int z_erofs_vle_unzip(struct super_block *sb, DBG_BUGON(page == NULL); DBG_BUGON(page->mapping == NULL);

- if (z_erofs_is_stagingpage(page)) - continue; + if (!z_erofs_is_stagingpage(page)) { #ifdef EROFS_FS_HAS_MANAGED_CACHE - if (page->mapping == mngda) { - DBG_BUGON(!PageUptodate(page)); - continue; - } + if (page->mapping == mngda) { + if (unlikely(!PageUptodate(page))) + err = -EIO; + continue; + } #endif

- /* only non-head page could be reused as a compressed page */ - pagenr = z_erofs_onlinepage_index(page); + /* + * only if non-head page can be selected + * for inplace decompression + */ + pagenr = z_erofs_onlinepage_index(page);

- DBG_BUGON(pagenr >= nr_pages); - DBG_BUGON(pages[pagenr]); - ++sparsemem_pages; - pages[pagenr] = page; + DBG_BUGON(pagenr >= nr_pages); + DBG_BUGON(pages[pagenr]); + ++sparsemem_pages; + pages[pagenr] = page;

- overlapped = true; + overlapped = true; + } + + /* PG_error needs checking for inplaced and staging pages */ + if (unlikely(PageError(page))) { + DBG_BUGON(PageUptodate(page)); + err = -EIO; + } }

+ if (unlikely(err)) + goto out; + llen = (nr_pages << PAGE_SHIFT) - work->pageofs;

if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN) { @@ -1078,6 +1092,8 @@ static inline bool recover_managed_page(struct z_erofs_vle_workgroup *grp, return true;

lock_page(page); + ClearPageError(page); + if (unlikely(!PagePrivate(page))) { set_page_private(page, (unsigned long)grp); SetPagePrivate(page);