generic: test small swapfile without page-aligned contiguous blocks

If a swapfile doesn't contain even a single page-aligned contiguous
range of blocks, it's an invalid swapfile, and might cause kernel
issue. This case covered commit 5808fecc5723 ("iomap: Fix negative
assignment to unsigned sis->pages in iomap_swapfile_activate").

Signed-off-by: Zorro Lang <zlang@redhat.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

diff --git a/tests/generic/641 b/tests/generic/641
new file mode 100755 (executable)
index 0000000..41b3504
--- /dev/null
+++ b/tests/generic/641
@@ -0,0 +1,77 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2021 Red Hat Inc.  All Rights Reserved.
+#
+# FS QA Test 641
+#
+# Test small swapfile which doesn't contain even a single page-aligned contiguous
+# range of blocks. This case covered commit 5808fecc5723 ("iomap: Fix negative
+# assignment to unsigned sis->pages in iomap_swapfile_activate").
+#
+. ./common/preamble
+_begin_fstest auto quick swap
+
+# Import common functions
+. ./common/filter
+
+# real QA test starts here
+_supported_fs generic
+_require_scratch
+_require_scratch_swapfile
+_require_test_program mkswap
+_require_test_program swapon
+_require_xfs_io_command fcollapse
+
+make_unaligned_swapfile()
+{
+       local fname=$1
+       local n=$((psize / bsize - 1))
+
+       # Make sure the swapfile doesn't contain even a single page-aligned
+       # contiguous range of blocks. This's necessary to cover the bug
+       $XFS_IO_PROG -f -t -c "pwrite 0 $(((psize + bsize) * n))" $fname >> $seqres.full 2>&1
+       for((i=1; i<=n; i++));do
+               $XFS_IO_PROG -c "fcollapse $(((psize - bsize) * i)) $bsize" $fname
+       done
+       chmod 0600 $fname
+       $CHATTR_PROG +C $fname > /dev/null 2>&1
+       $here/src/mkswap $fname
+}
+
+_scratch_mkfs >> $seqres.full 2>&1
+_scratch_mount
+psize=`get_page_size`
+bsize=`_get_file_block_size $SCRATCH_MNT`
+# Due to we need page-unaligned blocks, so blocksize < pagesize is necessary.
+# If not, try to make a smaller enough block size
+if [ $bsize -ge $psize ];then
+       _scratch_unmount
+       _scratch_mkfs_blocksized 1024 >> $seqres.full 2>&1
+       if [ $? -ne 0 ];then
+               _notrun "Can't make filesystem block size < page size."
+       fi
+       _scratch_mount
+       bsize=`_get_file_block_size $SCRATCH_MNT`
+       if [ $bsize -ne 1024 ];then
+               _notrun "Can't force 1024-byte file block size."
+       fi
+fi
+swapfile=$SCRATCH_MNT/$seq.swapfile
+make_unaligned_swapfile $swapfile
+# Expect EINVAL from swapon. If not, might miss 5808fecc5723 ("iomap: Fix
+# negative assignment to unsigned sis->pages in iomap_swapfile_activate")
+$here/src/swapon $swapfile
+# Further testing, check if swap size <= swapfile size, if swapon passed
+if [ $? -eq 0 ];then
+       swapsize=$(awk -v fname="$swapfile" '{if ($1~fname) print $3}' /proc/swaps)
+       swapsize=$((swapsize * 1024))
+       filesize=$(_get_filesize $swapfile)
+       if [ $swapsize -gt $filesize ]; then
+               echo "Allocated swap size($swapsize) shouldn't be greater than swapfile size($filesize)"
+       fi
+fi
+swapoff $swapfile 2>/dev/null
+
+# success, all done
+status=0
+exit

diff --git a/tests/generic/641.out b/tests/generic/641.out
new file mode 100644 (file)
index 0000000..83c9364
--- /dev/null
+++ b/tests/generic/641.out
@@ -0,0 +1,2 @@
+QA output created by 641
+swapon: Invalid argument