diff mbox series

[v2] generic: add a testcase to check the capability CAP_LINUX_IMMUTABLE

Message ID 20190508041119.25145-1-jiufei.xue@linux.alibaba.com (mailing list archive)
State New, archived
Headers show
Series [v2] generic: add a testcase to check the capability CAP_LINUX_IMMUTABLE | expand

Commit Message

Jiufei Xue May 8, 2019, 4:11 a.m. UTC 
It should return error while changing IMMUTABLE_FL flag if the process
has no capability CAP_LINUX_IMMUTABLE.

However, it's not true on overlayfs after kernel version v4.19 since
the process's subjective cred is overridden with ofs->creator_cred
before calling real vfs_ioctl.

The following patch for ovl fix the problem:
  "ovl: check the capability before cred overridden"

Add this testcase to cover this bug.

v2: add testcases to check APPEND_FL and clear these flags. Suggested by
Amir Goldstein.

Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
---
 common/config         |  1 +
 tests/generic/545     | 74 +++++++++++++++++++++++++++++++++++++++++++
 tests/generic/545.out | 10 ++++++
 tests/generic/group   |  1 +
 4 files changed, 86 insertions(+)
 create mode 100755 tests/generic/545
 create mode 100755 tests/generic/545.out

Comments

Amir Goldstein May 8, 2019, 6:24 a.m. UTC | #1 
On Wed, May 8, 2019 at 7:11 AM Jiufei Xue <jiufei.xue@linux.alibaba.com> wrote:
>
> It should return error while changing IMMUTABLE_FL flag if the process
> has no capability CAP_LINUX_IMMUTABLE.

and APPEND_FL

>
> However, it's not true on overlayfs after kernel version v4.19 since
> the process's subjective cred is overridden with ofs->creator_cred
> before calling real vfs_ioctl.
>
> The following patch for ovl fix the problem:
>   "ovl: check the capability before cred overridden"
>
> Add this testcase to cover this bug.
>
> v2: add testcases to check APPEND_FL and clear these flags. Suggested by
> Amir Goldstein.

Patch revision info goes after --- line (edit after fomat-patch), so it
doesn't end up in commit message

>
> Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
> ---
>  common/config         |  1 +
>  tests/generic/545     | 74 +++++++++++++++++++++++++++++++++++++++++++
>  tests/generic/545.out | 10 ++++++
>  tests/generic/group   |  1 +
>  4 files changed, 86 insertions(+)
>  create mode 100755 tests/generic/545
>  create mode 100755 tests/generic/545.out
>
> diff --git a/common/config b/common/config
> index 64f87057..364432bb 100644
> --- a/common/config
> +++ b/common/config
> @@ -196,6 +196,7 @@ export SQLITE3_PROG="$(type -P sqlite3)"
>  export TIMEOUT_PROG="$(type -P timeout)"
>  export SETCAP_PROG="$(type -P setcap)"
>  export GETCAP_PROG="$(type -P getcap)"
> +export CAPSH_PROG="$(type -P capsh)"
>  export CHECKBASHISMS_PROG="$(type -P checkbashisms)"
>  export XFS_INFO_PROG="$(type -P xfs_info)"
>  export DUPEREMOVE_PROG="$(type -P duperemove)"
> diff --git a/tests/generic/545 b/tests/generic/545
> new file mode 100755
> index 00000000..a7c142e2
> --- /dev/null
> +++ b/tests/generic/545
> @@ -0,0 +1,74 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2019 Alibaba Group.  All Rights Reserved.
> +#
> +# FS QA Test No. 545
> +#
> +# Check that we can't set the FS_APPEND_FL and FS_IMMUTABLE_FL inode
> +# flags without capbility CAP_LINUX_IMMUTABLE
> +#
> +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()
> +{

You must have cleanup of flags on both file also here in case test is
aborted (i.e. CTRL-C), so we have no immutable/append-only files
left behind in test partition.

> +    cd /
> +    rm -rf $tmp.* $testdir
> +}
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +. ./common/attr
> +
> +# real QA test starts here
> +_supported_os Linux
> +_require_chattr i
> +_require_chattr a
> +_require_command "$CAPSH_PROG" "capsh"
> +
> +rm -f $seqres.full
> +
> +echo "Format and mount"
> +testdir="$TEST_DIR/test-$seq"
> +rm -rf $testdir
> +mkdir $testdir
> +
> +echo "Create the original files"
> +touch $testdir/file1
> +touch $testdir/file2
> +
> +do_filter_output()
> +{
> +    err_str=`_filter_test_dir | grep "Operation not permitted"`
> +    test -n "$err_str" && echo "Operation not permitted"
> +}
> +
> +echo "Try to chattr +ia with capabilities CAP_LINUX_IMMUTABLE"
> +$CHATTR_PROG +a $testdir/file1 2>&1
> +$CHATTR_PROG +i $testdir/file1 2>&1
> +
> +echo "Try to chattr +ia/-ia without capability CAP_LINUX_IMMUTABLE"
> +$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG +a $testdir/file2" 2>&1 | do_filter_output
> +$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG +i $testdir/file2" 2>&1 | do_filter_output
> +
> +$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG -i $testdir/file1" 2>&1 | do_filter_output
> +$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG -a $testdir/file1" 2>&1 | do_filter_output
> +
> +echo "Try to chattr -ia with capability CAP_LINUX_IMMUTABLE"
> +$CHATTR_PROG -i $testdir/file1 2>&1
> +$CHATTR_PROG -a $testdir/file1 2>&1
> +
> +# in case chattr +ia succeed without capability
> +$CHATTR_PROG -i $testdir/file2 2>&1
> +$CHATTR_PROG -a $testdir/file2 2>&1

Might as well leave this one only in cleanup() as it is not
part of the test and it needs to be in cleanup() anyway.

Thanks,
Amir.
diff mbox series

Patch

diff --git a/common/config b/common/config
index 64f87057..364432bb 100644
--- a/common/config
+++ b/common/config
@@ -196,6 +196,7 @@  export SQLITE3_PROG="$(type -P sqlite3)"
 export TIMEOUT_PROG="$(type -P timeout)"
 export SETCAP_PROG="$(type -P setcap)"
 export GETCAP_PROG="$(type -P getcap)"
+export CAPSH_PROG="$(type -P capsh)"
 export CHECKBASHISMS_PROG="$(type -P checkbashisms)"
 export XFS_INFO_PROG="$(type -P xfs_info)"
 export DUPEREMOVE_PROG="$(type -P duperemove)"
diff --git a/tests/generic/545 b/tests/generic/545
new file mode 100755
index 00000000..a7c142e2
--- /dev/null
+++ b/tests/generic/545
@@ -0,0 +1,74 @@ 
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2019 Alibaba Group.  All Rights Reserved.
+#
+# FS QA Test No. 545
+#
+# Check that we can't set the FS_APPEND_FL and FS_IMMUTABLE_FL inode
+# flags without capbility CAP_LINUX_IMMUTABLE
+#
+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 -rf $tmp.* $testdir
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/attr
+
+# real QA test starts here
+_supported_os Linux
+_require_chattr i
+_require_chattr a
+_require_command "$CAPSH_PROG" "capsh"
+
+rm -f $seqres.full
+
+echo "Format and mount"
+testdir="$TEST_DIR/test-$seq"
+rm -rf $testdir
+mkdir $testdir
+
+echo "Create the original files"
+touch $testdir/file1
+touch $testdir/file2
+
+do_filter_output()
+{
+    err_str=`_filter_test_dir | grep "Operation not permitted"`
+    test -n "$err_str" && echo "Operation not permitted"
+}
+
+echo "Try to chattr +ia with capabilities CAP_LINUX_IMMUTABLE"
+$CHATTR_PROG +a $testdir/file1 2>&1
+$CHATTR_PROG +i $testdir/file1 2>&1
+
+echo "Try to chattr +ia/-ia without capability CAP_LINUX_IMMUTABLE"
+$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG +a $testdir/file2" 2>&1 | do_filter_output
+$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG +i $testdir/file2" 2>&1 | do_filter_output
+
+$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG -i $testdir/file1" 2>&1 | do_filter_output
+$CAPSH_PROG --drop=cap_linux_immutable -- -c "$CHATTR_PROG -a $testdir/file1" 2>&1 | do_filter_output
+
+echo "Try to chattr -ia with capability CAP_LINUX_IMMUTABLE"
+$CHATTR_PROG -i $testdir/file1 2>&1
+$CHATTR_PROG -a $testdir/file1 2>&1
+
+# in case chattr +ia succeed without capability
+$CHATTR_PROG -i $testdir/file2 2>&1
+$CHATTR_PROG -a $testdir/file2 2>&1
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/545.out b/tests/generic/545.out
new file mode 100755
index 00000000..8c6e4082
--- /dev/null
+++ b/tests/generic/545.out
@@ -0,0 +1,10 @@ 
+QA output created by 545
+Format and mount
+Create the original files
+Try to chattr +ia with capabilities CAP_LINUX_IMMUTABLE
+Try to chattr +ia/-ia without capability CAP_LINUX_IMMUTABLE
+Operation not permitted
+Operation not permitted
+Operation not permitted
+Operation not permitted
+Try to chattr -ia with capability CAP_LINUX_IMMUTABLE
diff --git a/tests/generic/group b/tests/generic/group
index 40deb4d0..7a457e81 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -547,3 +547,4 @@ 
 542 auto quick clone
 543 auto quick clone
 544 auto quick clone
+545 auto quick cap