Test two overlayfs file handle bugs: 1. Failure to query file handle size Fixed by kernel commit: ovl: return required buffer size for file handles 2. Kernel OOPS on open by hand crafted malformed file handle Fixed by kernel commit: ovl: potential crash in ovl_fid_to_fh() Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- tests/overlay/073 | 80 +++++++++++++++++++++++++++++++++++++++++++ tests/overlay/073.out | 2 ++ tests/overlay/group | 1 + 3 files changed, 83 insertions(+) create mode 100755 tests/overlay/073 create mode 100644 tests/overlay/073.out diff --git a/tests/overlay/073 b/tests/overlay/073 new file mode 100755 index 00000000..72233fae --- /dev/null +++ b/tests/overlay/073 @@ -0,0 +1,80 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020 CTERA Networks. All Rights Reserved. +# +# FS QA Test No. 073 +# +# Test two overlayfs file handle bugs: +# 1. Failure to query file handle size +# Fixed by kernel commit: +# ovl: return required buffer size for file handles +# +# 2. Kernel OOPS on open by hand crafted malformed file handle +# Fixed by kernel commit: +# ovl: potential crash in ovl_fid_to_fh() +# +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + #rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here + +_supported_fs overlay +_supported_os Linux +_require_scratch +_require_test_program "open_by_handle" +# We need to require all features together, because nfs_export cannot +# be enabled when index is disabled +_require_scratch_overlay_features index nfs_export + +rm -f $seqres.full + +_scratch_mkfs +_scratch_mount -o "index=on,nfs_export=on" + +testdir=$SCRATCH_MNT/testdir + +# Create directory with test file +$here/src/open_by_handle -cp $testdir + +# Test query file handle size on dir and file +$here/src/open_by_handle -pz $testdir + +# Export file handle into tmp file +$here/src/open_by_handle -o $tmp.file_handle $testdir + +# Verify open by exported file handle +$here/src/open_by_handle -i $tmp.file_handle $testdir + +# Mangle the exported file handle: +# handle_bytes = 1 +# handle_type = OVL_FILEID_V0 (0xfb) +# File handle is encoded in host order +# The command below crafts this header for little endian. +# On different big endian architectures the file handle will still +# be malformed just not with the specific values to trigger the bug +$XFS_IO_PROG -c "pwrite -S 0 0 8" -c "pwrite -S 1 0 1" -c "pwrite -S 0xfb 4 1" $tmp.file_handle >> $seqres.full + +# Verify failure to open by mangled file handle +# This will trigger NULL pointer dereference on affected kernels +$here/src/open_by_handle -i $tmp.file_handle $testdir 2>> $seqres.full && \ + _fail "open by mangaled file handle is expected to fail" + +echo "Silence is golden" +status=0 +exit diff --git a/tests/overlay/073.out b/tests/overlay/073.out new file mode 100644 index 00000000..d107704c --- /dev/null +++ b/tests/overlay/073.out @@ -0,0 +1,2 @@ +QA output created by 073 +Silence is golden diff --git a/tests/overlay/group b/tests/overlay/group index 82876d09..5625a46d 100644 --- a/tests/overlay/group +++ b/tests/overlay/group @@ -75,3 +75,4 @@ 070 auto quick copyup redirect nested 071 auto quick copyup redirect nested nonsamefs 072 auto quick copyup hardlink +073 auto quick exportfs dangerous -- 2.17.1