[3/6] sysvipc: Fix IPC_INFO and MSG_INFO handling [BZ #26639]
Commit Message
Both commands are Linux exntesions where the third argument is a
'struct msginfo' instead of 'struct msqid_ds' and its information
does not contain any time related fields (so there is no need to
extra conversion for __IPC_TIME64.
The regression testcase checks for Linux specifix SysV ipc message
control extension. For IPC_INFO/MSG_INFO it tries to match the values
against the tunable /proc values and for MSG_STAT/MSG_STAT_ANY it
check if the create message queue is within the global list returned
by the kernel.
Checked on x86_64-linux-gnu and on i686-linux-gnu (Linux v5.4 and on
Linux v4.15).
---
sysdeps/unix/sysv/linux/Makefile | 2 +-
sysdeps/unix/sysv/linux/msgctl.c | 22 ++-
sysdeps/unix/sysv/linux/tst-sysvmsg-linux.c | 203 ++++++++++++++++++++
3 files changed, 222 insertions(+), 5 deletions(-)
create mode 100644 sysdeps/unix/sysv/linux/tst-sysvmsg-linux.c
Comments
On Sep 28 2020, Adhemerval Zanella via Libc-alpha wrote:
> Both commands are Linux exntesions where the third argument is a
extensions
Andreas.
* Adhemerval Zanella via Libc-alpha:
> +static int
> +read_proc_file (const char *file)
> +{
> + FILE *f = fopen (file, "r");
> + if (f == NULL)
> + return -1;
> +
> + int v;
> + int r = fscanf (f, "%d", & v);
> + TEST_VERIFY_EXIT (r == 1);
> +
> + fclose (f);
> + return v;
> +}
You could use xfopen and xfclose.
> +/* Check if the message queue with IDX (index into the kernel's internal
> + array) matches the one with KEY. The CMD is either MSG_STAT or
> + MSG_STAT_ANY. */
> +
> +static bool
> +check_msginfo (int idx, key_t key, int cmd)
> +{
> + struct msqid_ds msginfo;
> + int mid = msgctl (idx, cmd, &msginfo);
> + /* Ignore unused array slot returned by the kernel or information from
> + unknown message queue. */
> + if ((mid == -1 && errno == EINVAL) || mid != msqid)
> + return false;
> +
> + if (mid == -1)
> + FAIL_EXIT1 ("msgctl with %s failed: %m",
> + cmd == MSG_STAT ? "MSG_STAT" : "MSG_STAT_ANY");
> +
> + if (msginfo.msg_perm.__key != key)
> + FAIL_EXIT1 ("msgid_ds::msg_perm::key (%d) != %d",
> + (int) msginfo.msg_perm.__key, (int) key);
> + if (msginfo.msg_perm.mode != MSGQ_MODE)
> + FAIL_EXIT1 ("msgid_ds::msg_perm::mode (%o) != %o",
> + msginfo.msg_perm.mode, MSGQ_MODE);
> + if (msginfo.msg_qnum != 0)
> + FAIL_EXIT1 ("msgid_ds::msg_qnum (%lu) != 0",
> + (long unsigned) msginfo.msg_qnum);
As in the other patch, you might want to use TEST_COMPARE here.
Rest looks okay, I think.
Thanks,
Florian
On 29/09/2020 04:57, Florian Weimer wrote:
> * Adhemerval Zanella via Libc-alpha:
>
>> +static int
>> +read_proc_file (const char *file)
>> +{
>> + FILE *f = fopen (file, "r");
>> + if (f == NULL)
>> + return -1;
>> +
>> + int v;
>> + int r = fscanf (f, "%d", & v);
>> + TEST_VERIFY_EXIT (r == 1);
>> +
>> + fclose (f);
>> + return v;
>> +}
>
> You could use xfopen and xfclose.
Indeed, I will change it.
>
>> +/* Check if the message queue with IDX (index into the kernel's internal
>> + array) matches the one with KEY. The CMD is either MSG_STAT or
>> + MSG_STAT_ANY. */
>> +
>> +static bool
>> +check_msginfo (int idx, key_t key, int cmd)
>> +{
>> + struct msqid_ds msginfo;
>> + int mid = msgctl (idx, cmd, &msginfo);
>> + /* Ignore unused array slot returned by the kernel or information from
>> + unknown message queue. */
>> + if ((mid == -1 && errno == EINVAL) || mid != msqid)
>> + return false;
>> +
>> + if (mid == -1)
>> + FAIL_EXIT1 ("msgctl with %s failed: %m",
>> + cmd == MSG_STAT ? "MSG_STAT" : "MSG_STAT_ANY");
>> +
>> + if (msginfo.msg_perm.__key != key)
>> + FAIL_EXIT1 ("msgid_ds::msg_perm::key (%d) != %d",
>> + (int) msginfo.msg_perm.__key, (int) key);
>> + if (msginfo.msg_perm.mode != MSGQ_MODE)
>> + FAIL_EXIT1 ("msgid_ds::msg_perm::mode (%o) != %o",
>> + msginfo.msg_perm.mode, MSGQ_MODE);
>> + if (msginfo.msg_qnum != 0)
>> + FAIL_EXIT1 ("msgid_ds::msg_qnum (%lu) != 0",
>> + (long unsigned) msginfo.msg_qnum);
>
> As in the other patch, you might want to use TEST_COMPARE here.
Yes, I changed it as well from the other patch review.
>
> Rest looks okay, I think.
>
> Thanks,
> Florian
>
On 29/09/2020 09:37, Adhemerval Zanella wrote:
>
>
> On 29/09/2020 04:57, Florian Weimer wrote:
>> * Adhemerval Zanella via Libc-alpha:
>>
>>> +static int
>>> +read_proc_file (const char *file)
>>> +{
>>> + FILE *f = fopen (file, "r");
>>> + if (f == NULL)
>>> + return -1;
>>> +
>>> + int v;
>>> + int r = fscanf (f, "%d", & v);
>>> + TEST_VERIFY_EXIT (r == 1);
>>> +
>>> + fclose (f);
>>> + return v;
>>> +}
>>
>> You could use xfopen and xfclose.
>
> Indeed, I will change it.
In fact I though about it before and for this test we do want to
check if the /proc file is accessible and just check against the
tunable value if it were the case. Otherwise the test will always
fail if /proc is not mounted (not really the expected scenario I
give you).
* Adhemerval Zanella:
> On 29/09/2020 09:37, Adhemerval Zanella wrote:
>>
>>
>> On 29/09/2020 04:57, Florian Weimer wrote:
>>> * Adhemerval Zanella via Libc-alpha:
>>>
>>>> +static int
>>>> +read_proc_file (const char *file)
>>>> +{
>>>> + FILE *f = fopen (file, "r");
>>>> + if (f == NULL)
>>>> + return -1;
>>>> +
>>>> + int v;
>>>> + int r = fscanf (f, "%d", & v);
>>>> + TEST_VERIFY_EXIT (r == 1);
>>>> +
>>>> + fclose (f);
>>>> + return v;
>>>> +}
>>>
>>> You could use xfopen and xfclose.
>>
>> Indeed, I will change it.
>
> In fact I though about it before and for this test we do want to
> check if the /proc file is accessible and just check against the
> tunable value if it were the case. Otherwise the test will always
> fail if /proc is not mounted (not really the expected scenario I
> give you).
Maybe add FAIL_UNSUPPORTED for this case at the start of the test?
Thanks,
Florian
On 29/09/2020 10:01, Florian Weimer wrote:
> * Adhemerval Zanella:
>
>> On 29/09/2020 09:37, Adhemerval Zanella wrote:
>>>
>>>
>>> On 29/09/2020 04:57, Florian Weimer wrote:
>>>> * Adhemerval Zanella via Libc-alpha:
>>>>
>>>>> +static int
>>>>> +read_proc_file (const char *file)
>>>>> +{
>>>>> + FILE *f = fopen (file, "r");
>>>>> + if (f == NULL)
>>>>> + return -1;
>>>>> +
>>>>> + int v;
>>>>> + int r = fscanf (f, "%d", & v);
>>>>> + TEST_VERIFY_EXIT (r == 1);
>>>>> +
>>>>> + fclose (f);
>>>>> + return v;
>>>>> +}
>>>>
>>>> You could use xfopen and xfclose.
>>>
>>> Indeed, I will change it.
>>
>> In fact I though about it before and for this test we do want to
>> check if the /proc file is accessible and just check against the
>> tunable value if it were the case. Otherwise the test will always
>> fail if /proc is not mounted (not really the expected scenario I
>> give you).
>
> Maybe add FAIL_UNSUPPORTED for this case at the start of the test?
I don't have a strong opinion, I will add the FAIL_UNSUPPORTED for
case /proc is not accessible then.
@@ -101,7 +101,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \
test-errno-linux tst-memfd_create tst-mlock2 tst-pkey \
tst-rlimit-infinity tst-ofdlocks tst-gettid tst-gettid-kill \
- tst-tgkill tst-sysvsem-linux
+ tst-tgkill tst-sysvsem-linux tst-sysvmsg-linux
tests-internal += tst-ofdlocks-compat tst-sigcontext-get_pc
CFLAGS-tst-sigcontext-get_pc.c = -fasynchronous-unwind-tables
@@ -90,8 +90,15 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf)
struct kernel_msqid64_ds ksemid, *arg = NULL;
if (buf != NULL)
{
- msqid64_to_kmsqid64 (buf, &ksemid);
- arg = &ksemid;
+ /* This is a Linux extension where kernel returns a 'struct msginfo'
+ instead. */
+ if (cmd == IPC_INFO || cmd == MSG_INFO)
+ arg = (struct kernel_msqid64_ds *) buf;
+ else
+ {
+ msqid64_to_kmsqid64 (buf, &ksemid);
+ arg = &ksemid;
+ }
}
# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
if (cmd == IPC_SET)
@@ -169,8 +176,15 @@ __msgctl (int msqid, int cmd, struct msqid_ds *buf)
struct __msqid64_ds msqid64, *buf64 = NULL;
if (buf != NULL)
{
- msqid_to_msqid64 (&msqid64, buf);
- buf64 = &msqid64;
+ /* This is a Linux extension where kernel returns a 'struct msginfo'
+ instead. */
+ if (cmd == IPC_INFO || cmd == MSG_INFO)
+ buf64 = (struct __msqid64_ds *) buf;
+ else
+ {
+ msqid_to_msqid64 (&msqid64, buf);
+ buf64 = &msqid64;
+ }
}
int ret = __msgctl64 (msqid, cmd, buf64);
new file mode 100644
@@ -0,0 +1,203 @@
+/* Basic tests for Linux SYSV message queue extensions.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C 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 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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 the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <sys/ipc.h>
+#include <sys/msg.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdio.h>
+
+#include <support/check.h>
+#include <support/temp_file.h>
+
+#define MSGQ_MODE 0644
+
+/* These are for the temporary file we generate. */
+static char *name;
+static int msqid;
+
+static void
+remove_msq (void)
+{
+ /* Enforce message queue removal in case of early test failure.
+ Ignore error since the msg may already have being removed. */
+ msgctl (msqid, IPC_RMID, NULL);
+}
+
+static void
+do_prepare (int argc, char *argv[])
+{
+ TEST_VERIFY_EXIT (create_temp_file ("tst-sysvmsg.", &name) != -1);
+}
+
+#define PREPARE do_prepare
+
+struct test_msginfo
+{
+ int msgmax;
+ int msgmnb;
+ int msgmni;
+};
+
+/* It tries to obtain some system-wide SysV messsage queue information from
+ /proc to check against IPC_INFO/MSG_INFO. The /proc only returns the
+ tunables value of MSGMAX, MSGMNB, and MSGMNI.
+
+ The kernel also returns constant value for MSGSSZ, MSGSEG and also MSGMAP,
+ MSGPOOL, and MSGTQL (for IPC_INFO). The issue to check them is they might
+ change over kernel releases. */
+
+static int
+read_proc_file (const char *file)
+{
+ FILE *f = fopen (file, "r");
+ if (f == NULL)
+ return -1;
+
+ int v;
+ int r = fscanf (f, "%d", & v);
+ TEST_VERIFY_EXIT (r == 1);
+
+ fclose (f);
+ return v;
+}
+
+static bool
+read_msg_stat (struct test_msginfo *tmsginfo)
+{
+ tmsginfo->msgmax = read_proc_file ("/proc/sys/kernel/msgmax");
+ if (tmsginfo->msgmax == -1)
+ return false;
+ tmsginfo->msgmnb = read_proc_file ("/proc/sys/kernel/msgmnb");
+ if (tmsginfo->msgmnb == -1)
+ return false;
+ tmsginfo->msgmni = read_proc_file ("/proc/sys/kernel/msgmni");
+ if (tmsginfo->msgmni == -1)
+ return false;
+ return true;
+}
+
+
+/* Check if the message queue with IDX (index into the kernel's internal
+ array) matches the one with KEY. The CMD is either MSG_STAT or
+ MSG_STAT_ANY. */
+
+static bool
+check_msginfo (int idx, key_t key, int cmd)
+{
+ struct msqid_ds msginfo;
+ int mid = msgctl (idx, cmd, &msginfo);
+ /* Ignore unused array slot returned by the kernel or information from
+ unknown message queue. */
+ if ((mid == -1 && errno == EINVAL) || mid != msqid)
+ return false;
+
+ if (mid == -1)
+ FAIL_EXIT1 ("msgctl with %s failed: %m",
+ cmd == MSG_STAT ? "MSG_STAT" : "MSG_STAT_ANY");
+
+ if (msginfo.msg_perm.__key != key)
+ FAIL_EXIT1 ("msgid_ds::msg_perm::key (%d) != %d",
+ (int) msginfo.msg_perm.__key, (int) key);
+ if (msginfo.msg_perm.mode != MSGQ_MODE)
+ FAIL_EXIT1 ("msgid_ds::msg_perm::mode (%o) != %o",
+ msginfo.msg_perm.mode, MSGQ_MODE);
+ if (msginfo.msg_qnum != 0)
+ FAIL_EXIT1 ("msgid_ds::msg_qnum (%lu) != 0",
+ (long unsigned) msginfo.msg_qnum);
+
+ return true;
+}
+
+static int
+do_test (void)
+{
+ atexit (remove_msq);
+
+ key_t key = ftok (name, 'G');
+ if (key == -1)
+ FAIL_EXIT1 ("ftok failed: %m");
+
+ msqid = msgget (key, MSGQ_MODE | IPC_CREAT);
+ if (msqid == -1)
+ FAIL_EXIT1 ("msgget failed: %m");
+
+ struct test_msginfo tipcinfo;
+ bool tipcget = read_msg_stat (&tipcinfo);
+
+ int msqidx;
+
+ {
+ struct msginfo ipcinfo;
+ msqidx = msgctl (msqid, IPC_INFO, (struct msqid_ds *) &ipcinfo);
+ if (msqidx == -1)
+ FAIL_EXIT1 ("msgctl with IPC_INFO failed: %m");
+
+ /* We only check if /proc is mounted. */
+ if (tipcget)
+ {
+ TEST_COMPARE (ipcinfo.msgmax, tipcinfo.msgmax);
+ TEST_COMPARE (ipcinfo.msgmnb, tipcinfo.msgmnb);
+ TEST_COMPARE (ipcinfo.msgmni, tipcinfo.msgmni);
+ }
+ }
+
+ /* Same as before but with MSG_INFO. */
+ {
+ struct msginfo ipcinfo;
+ msqidx = msgctl (msqid, MSG_INFO, (struct msqid_ds *) &ipcinfo);
+ if (msqidx == -1)
+ FAIL_EXIT1 ("msgctl with IPC_INFO failed: %m");
+
+ if (tipcget)
+ {
+ TEST_COMPARE (ipcinfo.msgmax, tipcinfo.msgmax);
+ TEST_COMPARE (ipcinfo.msgmnb, tipcinfo.msgmnb);
+ TEST_COMPARE (ipcinfo.msgmni, tipcinfo.msgmni);
+ }
+ }
+
+ /* We check if the created message queue shows in global list. */
+ bool found = false;
+ for (int i = 0; i <= msqidx; i++)
+ {
+ if (check_msginfo (i, key, MSG_STAT))
+ {
+ found = true;
+ break;
+ }
+
+ /* We can't tell apart if MSG_STAT_ANY is not supported (kernel older
+ than 4.17) or if the index used is invalid. So it just check if the
+ value returned from a valid call matches the created message
+ queue. */
+ check_msginfo (i, key, MSG_STAT_ANY);
+ }
+
+ if (!found)
+ FAIL_EXIT1 ("msgctl with MSG_STAT/MSG_STAT_ANY could not find the "
+ "created message queue");
+
+ if (msgctl (msqid, IPC_RMID, NULL) == -1)
+ FAIL_EXIT1 ("msgctl failed");
+
+ return 0;
+}
+
+#include <support/test-driver.c>