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import libnbd-1.6.0-5.module+el8.6.0+14156+faad4bd2

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CentOS Sources 2022-05-03 14:03:13 +00:00 committed by Stepan Oksanichenko
parent 80454192e2
commit b708f948ee
9 changed files with 496 additions and 9 deletions
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2
SOURCES/0001-copy-copy-nbd-to-sparse-file.sh-Skip-test-unless-nbd.patch
View File

@ -26,5 +26,5 @@ index aa2cb1b..47ff09a 100755
requires test -r /dev/zero
--
2.18.4
2.31.1

2
SOURCES/0002-generator-Refactor-CONNECT.START-state.patch
View File

@ -53,5 +53,5 @@ index 392879d..03b34c7 100644
CONNECT.CONNECTING:
--
2.18.4
2.31.1

2
SOURCES/0003-generator-Print-a-better-error-message-if-connect-2-.patch
View File

@ -44,5 +44,5 @@ index 03b34c7..98c26e5 100644
set_error (errno, "connect");
return 0;
--
2.18.4
2.31.1

2
SOURCES/0004-opt_go-Tolerate-unplanned-server-death.patch
View File

@ -55,5 +55,5 @@ index 2317b72..e5802f4 100644
return -1;
}
--
2.18.4
2.31.1

2
SOURCES/0005-security-Document-assignment-of-CVE-2021-20286.patch
View File

@ -36,5 +36,5 @@ index d8ead87..0cae846 100644
-Copyright (C) 2019 Red Hat Inc.
+Copyright (C) 2019-2021 Red Hat Inc.
--
2.18.4
2.31.1

163
SOURCES/0006-copy-Pass-in-dummy-variable-rather-than-errno-to-cal.patch Normal file
View File

@ -0,0 +1,163 @@
From 22572f8ac13e2e8daf91d227eac2f384303fb5b4 Mon Sep 17 00:00:00 2001
From: Eric Blake <eblake@redhat.com>
Date: Thu, 3 Feb 2022 14:25:57 -0600
Subject: [PATCH] copy: Pass in dummy variable rather than &errno to callback
In several places where asynch handlers manually call the provided
nbd_completion_callback, the value of errno is indeterminate (for
example, in file-ops.c:file_asynch_read(), the previous call to
file_synch_read() already triggered exit() on error, but does not
guarantee what is left in errno on success). As the callback should
be paying attention to the value of *error (to be fixed in the next
patch), we are better off ensuring that we pass in a pointer to a
known-zero value. Besides, passing in &errno carries a risk that if
the callback uses any other library function that alters errno prior
to dereferncing *error, it will no longer see the value we passed in.
Thus, it is easier to use a dummy variable on the stack than to mess
around with errno and it's magic macro expansion into a thread-local
storage location.
Note that several callsites then check if the callback returned -1,
and if so assume that the callback has caused errno to now have a sane
value to pass on to perror. In theory, the fact that we are no longer
passing in &errno means that if the callback assigns into *error but
did not otherwise affect errno (a tenuous assumption, given our
argument above that we could not even guarantee that the callback does
not accidentally alter errno prior to reading *error), our perror call
would no longer reflect the intended error value from the callback.
But in practice, since the callback never actually returned -1, nor
even assigned into *error, the call to perror is dead code; although I
have chosen to defer that additional cleanup to the next patch.
Message-Id: <20220203202558.203013-5-eblake@redhat.com>
Acked-by: Richard W.M. Jones <rjones@redhat.com>
Acked-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
(cherry picked from commit 794c8ce06e995ebd282e8f2b9465a06140572112)
Conflicts:
copy/file-ops.c - no backport of d5f65e56 ("copy: Do not use trim
for zeroing"), so asynch_trim needed same treatment
copy/multi-thread-copying.c - context due to missing refactoring
copy/null-ops.c - no backport of 0b16205e "copy: Implement "null:"
destination."
(cherry picked from commit 26e3dcf80815fe2db320d3046aabc2580c2f7a0d)
---
copy/file-ops.c | 22 +++++++++++++---------
copy/multi-thread-copying.c | 8 +++++---
2 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/copy/file-ops.c b/copy/file-ops.c
index 086348a..cc312b4 100644
--- a/copy/file-ops.c
+++ b/copy/file-ops.c
@@ -1,5 +1,5 @@
/* NBD client library in userspace.
- * Copyright (C) 2020 Red Hat Inc.
+ * Copyright (C) 2020-2022 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -158,10 +158,11 @@ file_asynch_read (struct rw *rw,
struct command *command,
nbd_completion_callback cb)
{
+ int dummy = 0;
+
file_synch_read (rw, slice_ptr (command->slice),
command->slice.len, command->offset);
- errno = 0;
- if (cb.callback (cb.user_data, &errno) == -1) {
+ if (cb.callback (cb.user_data, &dummy) == -1) {
perror (rw->name);
exit (EXIT_FAILURE);
}
@@ -172,10 +173,11 @@ file_asynch_write (struct rw *rw,
struct command *command,
nbd_completion_callback cb)
{
+ int dummy = 0;
+
file_synch_write (rw, slice_ptr (command->slice),
command->slice.len, command->offset);
- errno = 0;
- if (cb.callback (cb.user_data, &errno) == -1) {
+ if (cb.callback (cb.user_data, &dummy) == -1) {
perror (rw->name);
exit (EXIT_FAILURE);
}
@@ -185,10 +187,11 @@ static bool
file_asynch_trim (struct rw *rw, struct command *command,
nbd_completion_callback cb)
{
+ int dummy = 0;
+
if (!file_synch_trim (rw, command->offset, command->slice.len))
return false;
- errno = 0;
- if (cb.callback (cb.user_data, &errno) == -1) {
+ if (cb.callback (cb.user_data, &dummy) == -1) {
perror (rw->name);
exit (EXIT_FAILURE);
}
@@ -199,10 +202,11 @@ static bool
file_asynch_zero (struct rw *rw, struct command *command,
nbd_completion_callback cb)
{
+ int dummy = 0;
+
if (!file_synch_zero (rw, command->offset, command->slice.len))
return false;
- errno = 0;
- if (cb.callback (cb.user_data, &errno) == -1) {
+ if (cb.callback (cb.user_data, &dummy) == -1) {
perror (rw->name);
exit (EXIT_FAILURE);
}
diff --git a/copy/multi-thread-copying.c b/copy/multi-thread-copying.c
index a7aaa7d..2593ff7 100644
--- a/copy/multi-thread-copying.c
+++ b/copy/multi-thread-copying.c
@@ -1,5 +1,5 @@
/* NBD client library in userspace.
- * Copyright (C) 2020 Red Hat Inc.
+ * Copyright (C) 2020-2022 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -391,6 +391,7 @@ finished_read (void *vp, int *error)
bool last_is_hole = false;
uint64_t i;
struct command *newcommand;
+ int dummy = 0;
/* Iterate over whole blocks in the command, starting on a block
* boundary.
@@ -473,7 +474,7 @@ finished_read (void *vp, int *error)
/* Free the original command since it has been split into
* subcommands and the original is no longer needed.
*/
- free_command (command, &errno);
+ free_command (command, &dummy);
}
return 1; /* auto-retires the command */
@@ -498,6 +499,7 @@ static void
fill_dst_range_with_zeroes (struct command *command)
{
char *data;
+ int dummy = 0;
if (destination_is_zero)
goto free_and_return;
@@ -541,7 +543,7 @@ fill_dst_range_with_zeroes (struct command *command)
free (data);
free_and_return:
- free_command (command, &errno);
+ free_command (command, &dummy);
}
static int
--
2.31.1

318
SOURCES/0007-copy-CVE-2022-0485-Fail-nbdcopy-if-NBD-read-or-write.patch Normal file
View File

@ -0,0 +1,318 @@
From 1b0b732e6a9b4979fccf6a09eb6704264edf675d Mon Sep 17 00:00:00 2001
From: Eric Blake <eblake@redhat.com>
Date: Thu, 3 Feb 2022 14:25:58 -0600
Subject: [PATCH] copy: CVE-2022-0485: Fail nbdcopy if NBD read or write fails
nbdcopy has a nasty bug when performing multi-threaded copies using
asynchronous nbd calls - it was blindly treating the completion of an
asynchronous command as successful, rather than checking the *error
parameter. This can result in the silent creation of a corrupted
image in two different ways: when a read fails, we blindly wrote
garbage to the destination; when a write fails, we did not flag that
the destination was not written.
Since nbdcopy already calls exit() on a synchronous read or write
failure to a file, doing the same for an asynchronous op to an NBD
server is the simplest solution. A nicer solution, but more invasive
to code and thus not done here, might be to allow up to N retries of
the transaction (in case the read or write failure was transient), or
even having a mode where as much data is copied as possible (portions
of the copy that failed would be logged on stderr, and nbdcopy would
still fail with a non-zero exit status, but this would copy more than
just stopping at the first error, as can be done with rsync or
ddrescue).
Note that since we rely on auto-retiring and do NOT call
nbd_aio_command_completed, our completion callbacks must always return
1 (if they do not exit() first), even when acting on *error, so as not
leave the command allocated until nbd_close. As such, there is no
sane way to return an error to a manual caller of the callback, and
therefore we can drop dead code that calls perror() and exit() if the
callback "failed". It is also worth documenting the contract on when
we must manually call the callback during the asynch_zero callback, so
that we do not leak or double-free the command; thankfully, all the
existing code paths were correct.
The added testsuite script demonstrates several scenarios, some of
which fail without the rest of this patch in place, and others which
showcase ways in which sparse images can bypass errors.
Once backports are complete, a followup patch on the main branch will
edit docs/libnbd-security.pod with the mailing list announcement of
the stable branch commit ids and release versions that incorporate
this fix.
Reported-by: Nir Soffer <nsoffer@redhat.com>
Fixes: bc896eec4d ("copy: Implement multi-conn, multiple threads, multiple requests in flight.", v1.5.6)
Fixes: https://bugzilla.redhat.com/2046194
Message-Id: <20220203202558.203013-6-eblake@redhat.com>
Acked-by: Richard W.M. Jones <rjones@redhat.com>
Acked-by: Nir Soffer <nsoffer@redhat.com>
[eblake: fix error message per Nir, tweak requires lines in unit test per Rich]
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
(cherry picked from commit 8d444b41d09a700c7ee6f9182a649f3f2d325abb)
Conflicts:
copy/nbdcopy.h - copyright context
copy/null-ops.c - no backport of 0b16205e "copy: Implement "null:"
destination."
copy/copy-nbd-error.sh - no backport of d5f65e56 ("copy: Do not use
trim for zeroing"), so one test needed an additional error-trim-rate;
no backport of 4ff9e62d (copy: Add --request-size option") and friends, so
this version uses larger transactions, so change error rate of 0.5 to 1;
no backport of 0b16205e "copy: Implement "null:" destination.", so use
nbdkit null instead
Note that while the use of NBD_CMD_TRIM can create data corruption, it is
not as severe as what this patch fixes, since trim corruption will only
expose what had previously been on the disk, compared to this patch fixing
a potential leak of nbdcopy heap contents into the destination.
(cherry picked from commit 6c8f2f859926b82094fb5e85c446ea099700fa10)
---
TODO | 1 +
copy/Makefile.am | 4 +-
copy/copy-nbd-error.sh | 81 +++++++++++++++++++++++++++++++++++++
copy/file-ops.c | 17 +++-----
copy/multi-thread-copying.c | 13 ++++++
copy/nbdcopy.h | 7 ++--
6 files changed, 107 insertions(+), 16 deletions(-)
create mode 100755 copy/copy-nbd-error.sh
diff --git a/TODO b/TODO
index 510c219..19c21d4 100644
--- a/TODO
+++ b/TODO
@@ -35,6 +35,7 @@ nbdcopy:
- Better page cache usage, see nbdkit-file-plugin options
fadvise=sequential cache=none.
- Consider io_uring if there are performance bottlenecks.
+ - Configurable retries in response to read or write failures.
nbdfuse:
- If you write beyond the end of the virtual file, it returns EIO.
diff --git a/copy/Makefile.am b/copy/Makefile.am
index d318388..3406cd8 100644
--- a/copy/Makefile.am
+++ b/copy/Makefile.am
@@ -1,5 +1,5 @@
# nbd client library in userspace
-# Copyright (C) 2020 Red Hat Inc.
+# Copyright (C) 2020-2022 Red Hat Inc.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
@@ -30,6 +30,7 @@ EXTRA_DIST = \
copy-nbd-to-small-nbd-error.sh \
copy-nbd-to-sparse-file.sh \
copy-nbd-to-stdout.sh \
+ copy-nbd-error.sh \
copy-progress-bar.sh \
copy-sparse.sh \
copy-sparse-allocated.sh \
@@ -105,6 +106,7 @@ TESTS += \
copy-nbd-to-sparse-file.sh \
copy-stdin-to-nbd.sh \
copy-nbd-to-stdout.sh \
+ copy-nbd-error.sh \
copy-progress-bar.sh \
copy-sparse.sh \
copy-sparse-allocated.sh \
diff --git a/copy/copy-nbd-error.sh b/copy/copy-nbd-error.sh
new file mode 100755
index 0000000..bba71db
--- /dev/null
+++ b/copy/copy-nbd-error.sh
@@ -0,0 +1,81 @@
+#!/usr/bin/env bash
+# nbd client library in userspace
+# Copyright (C) 2022 Red Hat Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+# Tests several scenarios of handling NBD server errors
+# Serves as a regression test for the CVE-2022-0485 fix.
+
+. ../tests/functions.sh
+
+set -e
+set -x
+
+requires nbdkit --exit-with-parent --version
+requires nbdkit --filter=noextents null --version
+requires nbdkit --filter=error pattern --version
+requires nbdkit --filter=nozero memory --version
+
+fail=0
+
+# Failure to get block status should not be fatal, but merely downgrade to
+# reading the entire image as if data
+echo "Testing extents failures on source"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v --filter=error pattern 5M \
+ error-extents-rate=1 ] [ nbdkit --exit-with-parent -v null 5M ] || fail=1
+
+# Failure to read should be fatal
+echo "Testing read failures on non-sparse source"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v --filter=error pattern 5M \
+ error-pread-rate=1 ] [ nbdkit --exit-with-parent -v null 5M ] && fail=1
+
+# However, reliable block status on a sparse image can avoid the need to read
+echo "Testing read failures on sparse source"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v --filter=error null 5M \
+ error-pread-rate=1 ] [ nbdkit --exit-with-parent -v null 5M ] || fail=1
+
+# Failure to write data should be fatal
+echo "Testing write data failures on arbitrary destination"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v pattern 5M ] \
+ [ nbdkit --exit-with-parent -v --filter=error --filter=noextents \
+ memory 5M error-pwrite-rate=1 ] && fail=1
+
+# However, writing zeroes can bypass the need for normal writes
+echo "Testing write data failures from sparse source"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v null 5M ] \
+ [ nbdkit --exit-with-parent -v --filter=error --filter=noextents \
+ memory 5M error-pwrite-rate=1 ] || fail=1
+
+# Failure to write zeroes should be fatal
+echo "Testing write zero failures on arbitrary destination"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v null 5M ] \
+ [ nbdkit --exit-with-parent -v --filter=error memory 5M \
+ error-trim-rate=1 error-zero-rate=1 ] && fail=1
+
+# However, assuming/learning destination is zero can skip need to write
+echo "Testing write failures on pre-zeroed destination"
+$VG nbdcopy --destination-is-zero -- \
+ [ nbdkit --exit-with-parent -v null 5M ] \
+ [ nbdkit --exit-with-parent -v --filter=error memory 5M \
+ error-pwrite-rate=1 error-zero-rate=1 ] || fail=1
+
+# Likewise, when write zero is not advertised, fallback to normal write works
+echo "Testing write zeroes to destination without zero support"
+$VG nbdcopy -- [ nbdkit --exit-with-parent -v null 5M ] \
+ [ nbdkit --exit-with-parent -v --filter=nozero --filter=error memory 5M \
+ error-zero-rate=1 ] || fail=1
+
+exit $fail
diff --git a/copy/file-ops.c b/copy/file-ops.c
index cc312b4..b19af04 100644
--- a/copy/file-ops.c
+++ b/copy/file-ops.c
@@ -162,10 +162,8 @@ file_asynch_read (struct rw *rw,
file_synch_read (rw, slice_ptr (command->slice),
command->slice.len, command->offset);
- if (cb.callback (cb.user_data, &dummy) == -1) {
- perror (rw->name);
- exit (EXIT_FAILURE);
- }
+ /* file_synch_read called exit() on error */
+ cb.callback (cb.user_data, &dummy);
}
static void
@@ -177,10 +175,8 @@ file_asynch_write (struct rw *rw,
file_synch_write (rw, slice_ptr (command->slice),
command->slice.len, command->offset);
- if (cb.callback (cb.user_data, &dummy) == -1) {
- perror (rw->name);
- exit (EXIT_FAILURE);
- }
+ /* file_synch_write called exit() on error */
+ cb.callback (cb.user_data, &dummy);
}
static bool
@@ -206,10 +202,7 @@ file_asynch_zero (struct rw *rw, struct command *command,
if (!file_synch_zero (rw, command->offset, command->slice.len))
return false;
- if (cb.callback (cb.user_data, &dummy) == -1) {
- perror (rw->name);
- exit (EXIT_FAILURE);
- }
+ cb.callback (cb.user_data, &dummy);
return true;
}
diff --git a/copy/multi-thread-copying.c b/copy/multi-thread-copying.c
index 2593ff7..28749ae 100644
--- a/copy/multi-thread-copying.c
+++ b/copy/multi-thread-copying.c
@@ -28,6 +28,7 @@
#include <errno.h>
#include <assert.h>
#include <sys/stat.h>
+#include <inttypes.h>
#include <pthread.h>
@@ -374,6 +375,12 @@ finished_read (void *vp, int *error)
{
struct command *command = vp;
+ if (*error) {
+ fprintf (stderr, "read at offset %" PRId64 " failed: %s\n",
+ command->offset, strerror (*error));
+ exit (EXIT_FAILURE);
+ }
+
if (allocated || sparse_size == 0) {
/* If sparseness detection (see below) is turned off then we write
* the whole command.
@@ -552,6 +559,12 @@ free_command (void *vp, int *error)
struct command *command = vp;
struct buffer *buffer = command->slice.buffer;
+ if (*error) {
+ fprintf (stderr, "write at offset %" PRId64 " failed: %s\n",
+ command->offset, strerror (*error));
+ exit (EXIT_FAILURE);
+ }
+
if (buffer != NULL) {
if (--buffer->refs == 0) {
free (buffer->data);
diff --git a/copy/nbdcopy.h b/copy/nbdcopy.h
index 3dcc6df..9626a52 100644
--- a/copy/nbdcopy.h
+++ b/copy/nbdcopy.h
@@ -1,5 +1,5 @@
/* NBD client library in userspace.
- * Copyright (C) 2020 Red Hat Inc.
+ * Copyright (C) 2020-2022 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -134,7 +134,8 @@ struct rw_ops {
bool (*synch_zero) (struct rw *rw, uint64_t offset, uint64_t count);
/* Asynchronous I/O operations. These start the operation and call
- * 'cb' on completion.
+ * 'cb' on completion. 'cb' will return 1, for auto-retiring with
+ * asynchronous libnbd calls.
*
* The file_ops versions are actually implemented synchronously, but
* still call 'cb'.
@@ -156,7 +157,7 @@ struct rw_ops {
nbd_completion_callback cb);
/* Asynchronously zero. command->slice.buffer is not used. If not possible,
- * returns false.
+ * returns false. 'cb' must be called only if returning true.
*/
bool (*asynch_zero) (struct rw *rw, struct command *command,
nbd_completion_callback cb);
--
2.31.1

2
SOURCES/copy-patches.sh
View File

@ -6,7 +6,7 @@ set -e
# directory. Use it like this:
# ./copy-patches.sh
rhel_version=8.4
rhel_version=8.6
# Check we're in the right directory.
if [ ! -f libnbd.spec ]; then

12
SPECS/libnbd.spec
View File

@ -2,14 +2,14 @@
%global verify_tarball_signature 1
# If there are patches which touch autotools files, set this to 1.
%global patches_touch_autotools %{nil}
%global patches_touch_autotools 1
# The source directory.
%global source_directory 1.6-stable
Name: libnbd
Version: 1.6.0
Release: 4%{?dist}
Release: 5%{?dist}
Summary: NBD client library in userspace
License: LGPLv2+
@ -26,7 +26,7 @@ Source2: libguestfs.keyring
Source3: copy-patches.sh
# Patches come from this upstream branch:
# https://github.com/libguestfs/libnbd/tree/rhel-8.4
# https://github.com/libguestfs/libnbd/tree/rhel-8.6
# Patches.
Patch0001: 0001-copy-copy-nbd-to-sparse-file.sh-Skip-test-unless-nbd.patch
@ -34,6 +34,8 @@ Patch0002: 0002-generator-Refactor-CONNECT.START-state.patch
Patch0003: 0003-generator-Print-a-better-error-message-if-connect-2-.patch
Patch0004: 0004-opt_go-Tolerate-unplanned-server-death.patch
Patch0005: 0005-security-Document-assignment-of-CVE-2021-20286.patch
Patch0006: 0006-copy-Pass-in-dummy-variable-rather-than-errno-to-cal.patch
Patch0007: 0007-copy-CVE-2022-0485-Fail-nbdcopy-if-NBD-read-or-write.patch
%if 0%{patches_touch_autotools}
BuildRequires: autoconf, automake, libtool
@ -310,6 +312,10 @@ make %{?_smp_mflags} check || {
%changelog
* Mon Feb 7 2022 Richard W.M. Jones <rjones@redhat.com> - 1.6.0-5.el8
- Fix CVE-2022-0485: Fail nbdcopy if NBD read or write fails
resolves: rhbz#2045718
* Thu Sep 2 2021 Danilo C. L. de Paula <ddepaula@redhat.com> - 1.6.0-4.el8
- Resolves: bz#2000225
(Rebase virt:rhel module:stream based on AV-8.6)