lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240904.185915-mundane.creels.ceramic.region-AXUMFBqDC1ZD@cyphar.com>
Date: Thu, 5 Sep 2024 05:00:45 +1000
From: Aleksa Sarai <cyphar@...har.com>
To: Amir Goldstein <amir73il@...il.com>
Cc: fstests@...r.kernel.org, Alexander Viro <viro@...iv.linux.org.uk>, 
	Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>, Chuck Lever <chuck.lever@...cle.com>, 
	Jeff Layton <jlayton@...nel.org>, Alexander Aring <alex.aring@...il.com>, 
	Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, 
	Arnaldo Carvalho de Melo <acme@...nel.org>, Namhyung Kim <namhyung@...nel.org>, 
	Mark Rutland <mark.rutland@....com>, Alexander Shishkin <alexander.shishkin@...ux.intel.com>, 
	Jiri Olsa <jolsa@...nel.org>, Ian Rogers <irogers@...gle.com>, 
	Adrian Hunter <adrian.hunter@...el.com>, "Liang, Kan" <kan.liang@...ux.intel.com>, 
	Christoph Hellwig <hch@...radead.org>, Josef Bacik <josef@...icpanda.com>, 
	linux-fsdevel@...r.kernel.org, linux-nfs@...r.kernel.org, linux-kernel@...r.kernel.org, 
	linux-api@...r.kernel.org, linux-perf-users@...r.kernel.org
Subject: Re: [PATCH xfstests v3 2/2] generic/756: test
 name_to_handle_at(AT_HANDLE_MNT_ID_UNIQUE) explicitly

On 2024-09-04, Amir Goldstein <amir73il@...il.com> wrote:
> On Wed, Sep 4, 2024 at 7:57 PM Aleksa Sarai <cyphar@...har.com> wrote:
> >
> > In order to make sure we are actually testing AT_HANDLE_MNT_ID_UNIQUE,
> > add a test (based on generic/426) which runs the open_by_handle in a
> > mode where it will error out if there is a problem with getting mount
> > IDs. The test is skipped if the kernel doesn't support the necessary
> > features.
> >
> > Suggested-by: Amir Goldstein <amir73il@...il.com>
> > Signed-off-by: Aleksa Sarai <cyphar@...har.com>
> 
> Apart from one minor nits below, you may add:
> 
> Reviewed-by: Amir Goldstein <amir73il@...il.com>
> 
> > ---
> >  common/rc             | 24 ++++++++++++++++
> >  src/open_by_handle.c  | 63 ++++++++++++++++++++++++++++++++++-------
> >  tests/generic/756     | 65 +++++++++++++++++++++++++++++++++++++++++++
> >  tests/generic/756.out |  5 ++++
> >  4 files changed, 147 insertions(+), 10 deletions(-)
> >  create mode 100755 tests/generic/756
> >  create mode 100644 tests/generic/756.out
> >
> > diff --git a/common/rc b/common/rc
> > index 9da9fe188297..0beaf2ff1126 100644
> > --- a/common/rc
> > +++ b/common/rc
> > @@ -5178,6 +5178,30 @@ _require_fibmap()
> >         rm -f $file
> >  }
> >
> > +_require_statx_unique_mountid()
> > +{
> > +       # statx(STATX_MNT_ID=0x1000) was added in Linux 5.8.
> > +       # statx(STATX_MNT_ID_UNIQUE=0x4000) was added in Linux 6.9.
> > +       # We only need to check the latter.
> > +
> > +       export STATX_MNT_ID_UNIQUE=0x4000
> > +       local statx_mask=$(
> > +               ${XFS_IO_PROG} -c "statx -m $STATX_MNT_ID_UNIQUE -r" "$TEST_DIR" |
> > +               sed -En 's/stat\.mask = (0x[0-9a-f]+)/\1/p'
> > +       )
> > +
> > +       [[ $(( statx_mask & STATX_MNT_ID_UNIQUE )) == $((STATX_MNT_ID_UNIQUE)) ]] ||
> > +               _notrun "statx does not support STATX_MNT_ID_UNIQUE on this kernel"
> > +}
> > +
> > +_require_open_by_handle_unique_mountid()
> > +{
> > +       _require_test_program "open_by_handle"
> > +
> > +       $here/src/open_by_handle -C AT_HANDLE_MNT_ID_UNIQUE 2>&1 \
> > +               || _notrun "name_to_handle_at does not support AT_HANDLE_MNT_ID_UNIQUE"
> > +}
> > +
> >  _try_wipe_scratch_devs()
> >  {
> >         test -x "$WIPEFS_PROG" || return 0
> > diff --git a/src/open_by_handle.c b/src/open_by_handle.c
> > index 920ec7d9170b..b5c1a30abbbc 100644
> > --- a/src/open_by_handle.c
> > +++ b/src/open_by_handle.c
> > @@ -106,9 +106,11 @@ struct handle {
> >
> >  void usage(void)
> >  {
> > -       fprintf(stderr, "usage: open_by_handle [-cludmrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]\n");
> > +       fprintf(stderr, "usage: open_by_handle [-cludmMrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]\n");
> > +       fprintf(stderr, "       open_by_handle -C <feature>\n");
> >         fprintf(stderr, "\n");
> >         fprintf(stderr, "open_by_handle -c <test_dir> [N] - create N test files under test_dir, try to get file handles and exit\n");
> > +       fprintf(stderr, "open_by_handle -c <test_dir> [N] - create N test files under test_dir, try to get file handles and exit\n");
> >         fprintf(stderr, "open_by_handle    <test_dir> [N] - get file handles of test files, drop caches and try to open by handle\n");
> >         fprintf(stderr, "open_by_handle -n <test_dir> [N] - get file handles of test files and try to open by handle without drop caches\n");
> >         fprintf(stderr, "open_by_handle -k <test_dir> [N] - get file handles of files that are kept open, drop caches and try to open by handle\n");
> > @@ -117,19 +119,23 @@ void usage(void)
> >         fprintf(stderr, "open_by_handle -a <test_dir> [N] - write data to test files after open by handle\n");
> >         fprintf(stderr, "open_by_handle -l <test_dir> [N] - create hardlinks to test files, drop caches and try to open by handle\n");
> >         fprintf(stderr, "open_by_handle -u <test_dir> [N] - unlink (hardlinked) test files, drop caches and try to open by handle\n");
> > -       fprintf(stderr, "open_by_handle -U <test_dir> [N] - verify the mount ID returned with AT_HANDLE_MNT_ID_UNIQUE is correct\n");
> 
> I guess this was not supposed to be in the first patch

Yeah, it got mixed up when splitting the patch. I'll fix it up.

> >         fprintf(stderr, "open_by_handle -d <test_dir> [N] - unlink test files and hardlinks, drop caches and try to open by handle\n");
> >         fprintf(stderr, "open_by_handle -m <test_dir> [N] - rename test files, drop caches and try to open by handle\n");
> > +       fprintf(stderr, "open_by_handle -M <test_dir> [N] - do not silently skip the mount ID verifications\n");
> >         fprintf(stderr, "open_by_handle -p <test_dir>     - create/delete and try to open by handle also test_dir itself\n");
> >         fprintf(stderr, "open_by_handle -i <handles_file> <test_dir> [N] - read test files handles from file and try to open by handle\n");
> >         fprintf(stderr, "open_by_handle -o <handles_file> <test_dir> [N] - get file handles of test files and write handles to file\n");
> >         fprintf(stderr, "open_by_handle -s <test_dir> [N] - wait in sleep loop after opening files by handle to keep them open\n");
> >         fprintf(stderr, "open_by_handle -z <test_dir> [N] - query filesystem required buffer size\n");
> > +       fprintf(stderr, "\n");
> > +       fprintf(stderr, "open_by_handle -C <feature>      - check if <feature> is supported by the kernel.\n");
> > +       fprintf(stderr, "  <feature> can be any of the following values:\n");
> > +       fprintf(stderr, "  - AT_HANDLE_MNT_ID_UNIQUE\n");
> >         exit(EXIT_FAILURE);
> >  }
> >
> >  static int do_name_to_handle_at(const char *fname, struct file_handle *fh,
> > -                               int bufsz)
> > +                               int bufsz, bool force_check_mountid)
> >  {
> >         int ret;
> >         int mntid_short;
> > @@ -145,10 +151,15 @@ static int do_name_to_handle_at(const char *fname, struct file_handle *fh,
> >                         fprintf(stderr, "%s: statx(STATX_MNT_ID): %m\n", fname);
> >                         return EXIT_FAILURE;
> >                 }
> > -               if (!(statxbuf.stx_mask & STATX_MNT_ID))
> > +               if (!(statxbuf.stx_mask & STATX_MNT_ID)) {
> > +                       if (force_check_mountid) {
> > +                               fprintf(stderr, "%s: statx(STATX_MNT_ID) not supported by running kernel\n", fname);
> > +                               return EXIT_FAILURE;
> > +                       }
> >                         skip_mntid = true;
> > -               else
> > +               } else {
> >                         statx_mntid_short = statxbuf.stx_mnt_id;
> > +               }
> >         }
> >
> >         if (!skip_mntid_unique) {
> > @@ -160,10 +171,15 @@ static int do_name_to_handle_at(const char *fname, struct file_handle *fh,
> >                  * STATX_MNT_ID_UNIQUE was added fairly recently in Linux 6.8, so if the
> >                  * kernel doesn't give us a unique mount ID just skip it.
> >                  */
> > -               if (!(statxbuf.stx_mask & STATX_MNT_ID_UNIQUE))
> > +               if (!(statxbuf.stx_mask & STATX_MNT_ID_UNIQUE)) {
> > +                       if (force_check_mountid) {
> > +                               fprintf(stderr, "%s: statx(STATX_MNT_ID_UNIQUE) not supported by running kernel\n", fname);
> > +                               return EXIT_FAILURE;
> > +                       }
> >                         skip_mntid_unique = true;
> > -               else
> > +               } else {
> >                         statx_mntid_unique = statxbuf.stx_mnt_id;
> > +               }
> >         }
> >
> >         fh->handle_bytes = bufsz;
> > @@ -204,6 +220,10 @@ static int do_name_to_handle_at(const char *fname, struct file_handle *fh,
> >                                 return EXIT_FAILURE;
> >                         }
> >                         /* EINVAL means AT_HANDLE_MNT_ID_UNIQUE is not supported */
> > +                       if (force_check_mountid) {
> > +                               fprintf(stderr, "%s: name_to_handle_at(AT_HANDLE_MNT_ID_UNIQUE) not supported by running kernel\n", fname);
> > +                               return EXIT_FAILURE;
> > +                       }
> >                         skip_mntid_unique = true;
> >                 } else {
> >                         if (mntid_unique != statx_mntid_unique) {
> > @@ -216,6 +236,22 @@ static int do_name_to_handle_at(const char *fname, struct file_handle *fh,
> >         return 0;
> >  }
> >
> > +static int check_feature(const char *feature)
> > +{
> > +       if (!strcmp(feature, "AT_HANDLE_MNT_ID_UNIQUE")) {
> > +               int ret = name_to_handle_at(AT_FDCWD, ".", NULL, NULL, AT_HANDLE_MNT_ID_UNIQUE);
> > +               /* If AT_HANDLE_MNT_ID_UNIQUE is supported, we get EFAULT. */
> > +               if (ret < 0 && errno == EINVAL) {
> > +                       fprintf(stderr, "name_to_handle_at(AT_HANDLE_MNT_ID_UNIQUE) not supported by running kernel\n");
> > +                       return EXIT_FAILURE;
> > +               }
> > +               return 0;
> > +       }
> > +
> > +       fprintf(stderr, "unknown feature name '%s'\n", feature);
> > +       return EXIT_FAILURE;
> > +}
> > +
> >  int main(int argc, char **argv)
> >  {
> >         int     i, c;
> > @@ -235,16 +271,20 @@ int main(int argc, char **argv)
> >         int     create = 0, delete = 0, nlink = 1, move = 0;
> >         int     rd = 0, wr = 0, wrafter = 0, parent = 0;
> >         int     keepopen = 0, drop_caches = 1, sleep_loop = 0;
> > +       int force_check_mountid = 0;
> >         int     bufsz = MAX_HANDLE_SZ;
> >
> >         if (argc < 2)
> >                 usage();
> >
> > -       while ((c = getopt(argc, argv, "cludmrwapknhi:o:sz")) != -1) {
> > +       while ((c = getopt(argc, argv, "cC:ludmMrwapknhi:o:sz")) != -1) {
> >                 switch (c) {
> >                 case 'c':
> >                         create = 1;
> >                         break;
> > +               case 'C':
> > +                       /* Check kernel feature support. */
> > +                       return check_feature(optarg);
> >                 case 'w':
> >                         /* Write data before open_by_handle_at() */
> >                         wr = 1;
> > @@ -271,6 +311,9 @@ int main(int argc, char **argv)
> >                 case 'm':
> >                         move = 1;
> >                         break;
> > +               case 'M':
> > +                       force_check_mountid = 1;
> > +                       break;
> >                 case 'p':
> >                         parent = 1;
> >                         break;
> > @@ -403,7 +446,7 @@ int main(int argc, char **argv)
> >                                 return EXIT_FAILURE;
> >                         }
> >                 } else {
> > -                       ret = do_name_to_handle_at(fname, &handle[i].fh, bufsz);
> > +                       ret = do_name_to_handle_at(fname, &handle[i].fh, bufsz, force_check_mountid);
> >                         if (ret)
> >                                 return EXIT_FAILURE;
> >                 }
> > @@ -433,7 +476,7 @@ int main(int argc, char **argv)
> >                                 return EXIT_FAILURE;
> >                         }
> >                 } else {
> > -                       ret = do_name_to_handle_at(test_dir, &dir_handle.fh, bufsz);
> > +                       ret = do_name_to_handle_at(test_dir, &dir_handle.fh, bufsz, force_check_mountid);
> >                         if (ret)
> >                                 return EXIT_FAILURE;
> >                 }
> > diff --git a/tests/generic/756 b/tests/generic/756
> > new file mode 100755
> > index 000000000000..c7a82cfd25f4
> > --- /dev/null
> > +++ b/tests/generic/756
> > @@ -0,0 +1,65 @@
> > +#! /bin/bash
> > +# SPDX-License-Identifier: GPL-2.0
> > +# Copyright (C) 2017 CTERA Networks. All Rights Reserved.
> > +# Copyright (C) 2024 Aleksa Sarai <cyphar@...har.com>
> > +#
> > +# FS QA Test No. 756
> > +#
> > +# Check stale handles pointing to unlinked files and non-stale handles pointing
> > +# to linked files while verifying that u64 mount IDs are correctly returned.
> > +#
> > +. ./common/preamble
> > +_begin_fstest auto quick exportfs
> > +
> > +# Import common functions.
> > +. ./common/filter
> > +
> > +
> > +# Modify as appropriate.
> > +_require_test
> > +# _require_exportfs and  already requires open_by_handle, but let's not count on it
> > +_require_test_program "open_by_handle"
> > +_require_exportfs
> > +# We need both STATX_MNT_ID_UNIQUE and AT_HANDLE_MNT_ID_UNIQUE.
> > +_require_statx_unique_mountid
> > +_require_open_by_handle_unique_mountid
> > +
> > +NUMFILES=1024
> > +testdir=$TEST_DIR/$seq-dir
> > +mkdir -p $testdir
> > +
> > +# Create empty test files in test dir
> > +create_test_files()
> > +{
> > +       local dir=$1
> > +
> > +       mkdir -p $dir
> > +       rm -f $dir/*
> > +       $here/src/open_by_handle -c $dir $NUMFILES
> > +}
> > +
> > +# Test encode/decode file handles
> > +test_file_handles()
> > +{
> > +       local dir=$1
> > +       local opt=$2
> > +
> > +       echo test_file_handles $* | _filter_test_dir
> > +       $here/src/open_by_handle $opt $dir $NUMFILES
> > +}
> > +
> > +# Check stale handles to deleted files
> > +create_test_files $testdir
> > +test_file_handles $testdir -Md
> > +
> > +# Check non-stale handles to linked files
> > +create_test_files $testdir
> > +test_file_handles $testdir -M
> > +
> > +# Check non-stale handles to files that were hardlinked and original deleted
> > +create_test_files $testdir
> > +test_file_handles $testdir -Ml
> > +test_file_handles $testdir -Mu
> > +
> > +status=0
> > +exit
> > diff --git a/tests/generic/756.out b/tests/generic/756.out
> > new file mode 100644
> > index 000000000000..48aed88d87b9
> > --- /dev/null
> > +++ b/tests/generic/756.out
> > @@ -0,0 +1,5 @@
> > +QA output created by 756
> > +test_file_handles TEST_DIR/756-dir -Md
> > +test_file_handles TEST_DIR/756-dir -M
> > +test_file_handles TEST_DIR/756-dir -Ml
> > +test_file_handles TEST_DIR/756-dir -Mu
> > --
> > 2.46.0
> >

-- 
Aleksa Sarai
Senior Software Engineer (Containers)
SUSE Linux GmbH
<https://www.cyphar.com/>

Download attachment "signature.asc" of type "application/pgp-signature" (229 bytes)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ