From: Gao Xiang <gaoxiang25@huawei.com>
Date: Mon, 19 Aug 2019 18:34:21 +0800
Subject: staging: erofs: some compressed cluster should be submitted for
 corrupted images
Git-commit: ee45197c807895e156b2be0abcaebdfc116487c8
Patch-mainline: 5.4-rc1
References: bnc#1151927 5.3.6

As reported by erofs_utils fuzzer, a logical page can belong
to at most 2 compressed clusters, if one compressed cluster
is corrupted, but the other has been ready in submitting chain.

The chain needs to submit anyway in order to keep the page
working properly (page unlocked with PG_error set, PG_uptodate
not set).

Let's fix it now.

Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20190819103426.87579-2-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/staging/erofs/unzip_vle.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -1498,19 +1498,18 @@ static int z_erofs_vle_normalaccess_read
 	err = z_erofs_do_read_page(&f, page, &pagepool);
 	(void)z_erofs_vle_work_iter_end(&f.builder);
 
-	if (err) {
+	/* if some compressed cluster ready, need submit them anyway */
+	z_erofs_submit_and_unzip(&f, &pagepool, true);
+
+	if (err)
 		errln("%s, failed to read, err [%d]", __func__, err);
-		goto out;
-	}
 
-	z_erofs_submit_and_unzip(&f, &pagepool, true);
-out:
 	if (f.map.mpage)
 		put_page(f.map.mpage);
 
 	/* clean up the remaining free pages */
 	put_pages_list(&pagepool);
-	return 0;
+	return err;
 }
 
 static int z_erofs_vle_normalaccess_readpages(struct file *filp,