From: Eric Biggers <ebiggers@kernel.org> To: fstests@vger.kernel.org Cc: Jaegeuk Kim <jaegeuk@kernel.org>, linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, "Theodore Y . Ts'o" <tytso@mit.edu>, linux-f2fs-devel@lists.sourceforge.net Subject: [PATCH v4 5/8] generic: test corrupting verity files Date: Mon, 30 Sep 2019 14:15:50 -0700 [thread overview] Message-ID: <20190930211553.64208-6-ebiggers@kernel.org> (raw) In-Reply-To: <20190930211553.64208-1-ebiggers@kernel.org> From: Eric Biggers <ebiggers@google.com> This test corrupts various parts of the contents of a verity file, or parts of its Merkle tree, by writing directly to the block device. It verifies that this causes I/O errors when the relevant part of the contents is later read by any means. Signed-off-by: Eric Biggers <ebiggers@google.com> --- tests/generic/902 | 154 ++++++++++++++++++++++++++++++++++++++++++ tests/generic/902.out | 91 +++++++++++++++++++++++++ tests/generic/group | 1 + 3 files changed, 246 insertions(+) create mode 100755 tests/generic/902 create mode 100644 tests/generic/902.out diff --git a/tests/generic/902 b/tests/generic/902 new file mode 100755 index 00000000..5ef2cca1 --- /dev/null +++ b/tests/generic/902 @@ -0,0 +1,154 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright 2018 Google LLC +# +# FS QA Test generic/902 +# +# Test corrupting verity files. This test corrupts various parts of the +# contents of a verity file, or parts of its Merkle tree, by writing directly to +# the block device. It verifies that this causes I/O errors when the relevant +# part of the contents is later read by any means. +# +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 +. ./common/verity + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here +_supported_fs generic +_supported_os Linux +_require_scratch_verity + +_scratch_mkfs_verity &>> $seqres.full +_scratch_mount +fsv_orig_file=$SCRATCH_MNT/file +fsv_file=$SCRATCH_MNT/file.fsv + +setup_zeroed_file() +{ + local len=$1 + local sparse=$2 + + if $sparse; then + dd if=/dev/zero of=$fsv_orig_file bs=1 count=0 seek=$len \ + status=none + else + head -c $len /dev/zero > $fsv_orig_file + fi + cp $fsv_orig_file $fsv_file + _fsv_enable $fsv_file + md5sum $fsv_file |& _filter_scratch +} + +filter_sigbus() +{ + sed -e 's/.*Bus error.*/Bus error/' +} + +round_up_to_page_boundary() +{ + local n=$1 + local page_size=$(get_page_size) + + echo $(( (n + page_size - 1) & ~(page_size - 1) )) +} + +corruption_test() +{ + local file_len=$1 + local zap_offset=$2 + local zap_len=$3 + local is_merkle_tree=${4:-false} # if true, zap tree instead of data + local use_sparse_file=${5:-false} + local page_aligned_eof=$(round_up_to_page_boundary $file_len) + local measurement + + if $is_merkle_tree; then + local corrupt_func=_fsv_scratch_corrupt_merkle_tree + else + local corrupt_func=_fsv_scratch_corrupt_bytes + fi + + local msg="Corruption test:" + msg+=" file_len=$file_len" + if $use_sparse_file; then + msg+=" (sparse)" + fi + msg+=" zap_offset=$zap_offset" + if $is_merkle_tree; then + msg+=" (in Merkle tree)" + fi + msg+=" zap_len=$zap_len" + + _fsv_scratch_begin_subtest "$msg" + setup_zeroed_file $file_len $use_sparse_file + cmp $fsv_file $fsv_orig_file + echo "Corrupting bytes..." + head -c $zap_len /dev/zero | tr '\0' X \ + | $corrupt_func $fsv_file $zap_offset + + echo "Validating corruption (reading full file)..." + _scratch_cycle_mount + md5sum $fsv_file |& _filter_scratch + + echo "Validating corruption (direct I/O)..." + _scratch_cycle_mount + dd if=$fsv_file bs=$FSV_BLOCK_SIZE iflag=direct status=none \ + of=/dev/null |& _filter_scratch + + if ! $is_merkle_tree; then + echo "Validating corruption (reading just corrupted part)..." + dd if=$fsv_file bs=1 skip=$zap_offset count=$zap_len \ + of=/dev/null status=none |& _filter_scratch + fi + + echo "Validating corruption (reading full file via mmap)..." + bash -c "trap '' SIGBUS; $XFS_IO_PROG -r $fsv_file \ + -c 'mmap -r 0 $page_aligned_eof' \ + -c 'mread 0 $file_len'" |& filter_sigbus + + if ! $is_merkle_tree; then + echo "Validating corruption (reading just corrupted part via mmap)..." + bash -c "trap '' SIGBUS; $XFS_IO_PROG -r $fsv_file \ + -c 'mmap -r 0 $page_aligned_eof' \ + -c 'mread $zap_offset $zap_len'" |& filter_sigbus + fi +} + +corruption_test 131072 0 1 +corruption_test 131072 4095 1 +corruption_test 131072 65536 65536 +corruption_test 131072 131071 1 + +# Non-zeroed bytes in the final partial block beyond EOF should cause reads to +# fail too. Such bytes would be visible via mmap(). +corruption_test 130999 131000 72 + +# Merkle tree corruption. +corruption_test 200000 100 10 true + +# Sparse file. Corrupting the Merkle tree should still cause reads to fail, +# i.e. the filesystem must verify holes. +corruption_test 200000 100 10 true true + +# success, all done +status=0 +exit diff --git a/tests/generic/902.out b/tests/generic/902.out new file mode 100644 index 00000000..15fe691e --- /dev/null +++ b/tests/generic/902.out @@ -0,0 +1,91 @@ +QA output created by 902 + +# Corruption test: file_len=131072 zap_offset=0 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=4095 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=65536 zap_len=65536 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=131071 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=130999 zap_offset=131000 zap_len=72 +f5cca0d7fbb8b02bc6118a9954d5d306 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=200000 zap_offset=100 (in Merkle tree) zap_len=10 +4a1e4325031b13f933ac4f1db9ecb63f SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error + +# Corruption test: file_len=200000 (sparse) zap_offset=100 (in Merkle tree) zap_len=10 +4a1e4325031b13f933ac4f1db9ecb63f SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error diff --git a/tests/generic/group b/tests/generic/group index a0450d42..22df626f 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -572,3 +572,4 @@ 567 auto quick rw punch 900 auto quick verity 901 auto quick verity +902 auto quick verity -- 2.23.0.444.g18eeb5a265-goog
WARNING: multiple messages have this Message-ID (diff)
From: Eric Biggers <ebiggers@kernel.org> To: fstests@vger.kernel.org Cc: linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Jaegeuk Kim <jaegeuk@kernel.org>, "Theodore Y . Ts'o" <tytso@mit.edu> Subject: [PATCH v4 5/8] generic: test corrupting verity files Date: Mon, 30 Sep 2019 14:15:50 -0700 [thread overview] Message-ID: <20190930211553.64208-6-ebiggers@kernel.org> (raw) Message-ID: <20190930211550.R7jpdFeYIfSYB-94acgSMip2RYFvRc7_v4b7X3avqNY@z> (raw) In-Reply-To: <20190930211553.64208-1-ebiggers@kernel.org> From: Eric Biggers <ebiggers@google.com> This test corrupts various parts of the contents of a verity file, or parts of its Merkle tree, by writing directly to the block device. It verifies that this causes I/O errors when the relevant part of the contents is later read by any means. Signed-off-by: Eric Biggers <ebiggers@google.com> --- tests/generic/902 | 154 ++++++++++++++++++++++++++++++++++++++++++ tests/generic/902.out | 91 +++++++++++++++++++++++++ tests/generic/group | 1 + 3 files changed, 246 insertions(+) create mode 100755 tests/generic/902 create mode 100644 tests/generic/902.out diff --git a/tests/generic/902 b/tests/generic/902 new file mode 100755 index 00000000..5ef2cca1 --- /dev/null +++ b/tests/generic/902 @@ -0,0 +1,154 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright 2018 Google LLC +# +# FS QA Test generic/902 +# +# Test corrupting verity files. This test corrupts various parts of the +# contents of a verity file, or parts of its Merkle tree, by writing directly to +# the block device. It verifies that this causes I/O errors when the relevant +# part of the contents is later read by any means. +# +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 +. ./common/verity + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here +_supported_fs generic +_supported_os Linux +_require_scratch_verity + +_scratch_mkfs_verity &>> $seqres.full +_scratch_mount +fsv_orig_file=$SCRATCH_MNT/file +fsv_file=$SCRATCH_MNT/file.fsv + +setup_zeroed_file() +{ + local len=$1 + local sparse=$2 + + if $sparse; then + dd if=/dev/zero of=$fsv_orig_file bs=1 count=0 seek=$len \ + status=none + else + head -c $len /dev/zero > $fsv_orig_file + fi + cp $fsv_orig_file $fsv_file + _fsv_enable $fsv_file + md5sum $fsv_file |& _filter_scratch +} + +filter_sigbus() +{ + sed -e 's/.*Bus error.*/Bus error/' +} + +round_up_to_page_boundary() +{ + local n=$1 + local page_size=$(get_page_size) + + echo $(( (n + page_size - 1) & ~(page_size - 1) )) +} + +corruption_test() +{ + local file_len=$1 + local zap_offset=$2 + local zap_len=$3 + local is_merkle_tree=${4:-false} # if true, zap tree instead of data + local use_sparse_file=${5:-false} + local page_aligned_eof=$(round_up_to_page_boundary $file_len) + local measurement + + if $is_merkle_tree; then + local corrupt_func=_fsv_scratch_corrupt_merkle_tree + else + local corrupt_func=_fsv_scratch_corrupt_bytes + fi + + local msg="Corruption test:" + msg+=" file_len=$file_len" + if $use_sparse_file; then + msg+=" (sparse)" + fi + msg+=" zap_offset=$zap_offset" + if $is_merkle_tree; then + msg+=" (in Merkle tree)" + fi + msg+=" zap_len=$zap_len" + + _fsv_scratch_begin_subtest "$msg" + setup_zeroed_file $file_len $use_sparse_file + cmp $fsv_file $fsv_orig_file + echo "Corrupting bytes..." + head -c $zap_len /dev/zero | tr '\0' X \ + | $corrupt_func $fsv_file $zap_offset + + echo "Validating corruption (reading full file)..." + _scratch_cycle_mount + md5sum $fsv_file |& _filter_scratch + + echo "Validating corruption (direct I/O)..." + _scratch_cycle_mount + dd if=$fsv_file bs=$FSV_BLOCK_SIZE iflag=direct status=none \ + of=/dev/null |& _filter_scratch + + if ! $is_merkle_tree; then + echo "Validating corruption (reading just corrupted part)..." + dd if=$fsv_file bs=1 skip=$zap_offset count=$zap_len \ + of=/dev/null status=none |& _filter_scratch + fi + + echo "Validating corruption (reading full file via mmap)..." + bash -c "trap '' SIGBUS; $XFS_IO_PROG -r $fsv_file \ + -c 'mmap -r 0 $page_aligned_eof' \ + -c 'mread 0 $file_len'" |& filter_sigbus + + if ! $is_merkle_tree; then + echo "Validating corruption (reading just corrupted part via mmap)..." + bash -c "trap '' SIGBUS; $XFS_IO_PROG -r $fsv_file \ + -c 'mmap -r 0 $page_aligned_eof' \ + -c 'mread $zap_offset $zap_len'" |& filter_sigbus + fi +} + +corruption_test 131072 0 1 +corruption_test 131072 4095 1 +corruption_test 131072 65536 65536 +corruption_test 131072 131071 1 + +# Non-zeroed bytes in the final partial block beyond EOF should cause reads to +# fail too. Such bytes would be visible via mmap(). +corruption_test 130999 131000 72 + +# Merkle tree corruption. +corruption_test 200000 100 10 true + +# Sparse file. Corrupting the Merkle tree should still cause reads to fail, +# i.e. the filesystem must verify holes. +corruption_test 200000 100 10 true true + +# success, all done +status=0 +exit diff --git a/tests/generic/902.out b/tests/generic/902.out new file mode 100644 index 00000000..15fe691e --- /dev/null +++ b/tests/generic/902.out @@ -0,0 +1,91 @@ +QA output created by 902 + +# Corruption test: file_len=131072 zap_offset=0 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=4095 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=65536 zap_len=65536 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=131072 zap_offset=131071 zap_len=1 +0dfbe8aa4c20b52e1b8bf3cb6cbdf193 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=130999 zap_offset=131000 zap_len=72 +f5cca0d7fbb8b02bc6118a9954d5d306 SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading just corrupted part)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error +Validating corruption (reading just corrupted part via mmap)... +Bus error + +# Corruption test: file_len=200000 zap_offset=100 (in Merkle tree) zap_len=10 +4a1e4325031b13f933ac4f1db9ecb63f SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error + +# Corruption test: file_len=200000 (sparse) zap_offset=100 (in Merkle tree) zap_len=10 +4a1e4325031b13f933ac4f1db9ecb63f SCRATCH_MNT/file.fsv +Corrupting bytes... +Validating corruption (reading full file)... +md5sum: SCRATCH_MNT/file.fsv: Input/output error +Validating corruption (direct I/O)... +dd: error reading 'SCRATCH_MNT/file.fsv': Input/output error +Validating corruption (reading full file via mmap)... +Bus error diff --git a/tests/generic/group b/tests/generic/group index a0450d42..22df626f 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -572,3 +572,4 @@ 567 auto quick rw punch 900 auto quick verity 901 auto quick verity +902 auto quick verity -- 2.23.0.444.g18eeb5a265-goog
next prev parent reply other threads:[~2019-09-30 21:15 UTC|newest] Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-09-30 21:15 [PATCH v4 0/8] xfstests: add fs-verity tests Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 1/8] common/filter: add _filter_xfs_io_fiemap() Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 2/8] common/verity: add common functions for testing fs-verity Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 3/8] generic: test general behavior of verity files Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 4/8] generic: test access controls on the fs-verity ioctls Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` Eric Biggers [this message] 2019-09-30 21:15 ` [PATCH v4 5/8] generic: test corrupting verity files Eric Biggers 2019-09-30 21:15 ` [PATCH v4 6/8] generic: test that fs-verity is using the correct measurement values Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 7/8] generic: test using fs-verity and fscrypt simultaneously Eric Biggers 2019-09-30 21:15 ` Eric Biggers 2019-09-30 21:15 ` [PATCH v4 8/8] generic: test the fs-verity built-in signature verification support Eric Biggers 2019-09-30 21:15 ` Eric Biggers
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