From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 4BEE63858D32 for ; Tue, 8 Nov 2022 15:01:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 4BEE63858D32 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667919659; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type; bh=kjrp/J8/N0Mz+9C5g3vOZbLJZhBKX/BV60C0lIYrM9M=; b=FrZeAAoKZhxszPKuDovx7DLbUcAxNRUjRhGACZnVzQldXqHEOnXgnEbpuL8SAak1hFeIzG H0sM8g37aHAQ3ctDrmmTxJBl7kh6728VgVNCCVOqnb8lWoskE4Sf5HrDvX/IYq9aNwZNMw 7BgGarkBMsadcSBXBITLl7NhF+P8cgg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-215-RJ0y2HW9MKOdpfxstocgSQ-1; Tue, 08 Nov 2022 10:00:58 -0500 X-MC-Unique: RJ0y2HW9MKOdpfxstocgSQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 47BA52A5955C for ; Tue, 8 Nov 2022 15:00:58 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.2.16.65]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CC8572028CE4 for ; Tue, 8 Nov 2022 15:00:57 +0000 (UTC) From: Florian Weimer To: libc-alpha@sourceware.org Subject: [PATCH] Linux: Support __IPC_64 in sysvctl *ctl command arguments Date: Tue, 08 Nov 2022 16:00:56 +0100 Message-ID: <87bkphij87.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-11.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Old applications pass __IPC_64 as part of the command argument because old glibc did not check for unknown commands, and passed through the arguments directly to the kernel, without adding __IPC_64. Applications need to continue doing that for old glibc compatibility, so this commit enables this approach in current glibc. For msgctl and shmctl, if no translation is required, make direct system calls, as we did before the time64 changes. If translation is required, mask __IPC_64 from the command argument. For semctl, the union-in-vararg argument handling means that translation is needed on all architectures. Tested on i686-linux-gnu, powerpc64le-linux-gnu, x86_64-linux-gnu. Built with build-many-glibcs.py. --- sysdeps/unix/sysv/linux/ipc_priv.h | 6 ++++++ sysdeps/unix/sysv/linux/msgctl.c | 38 +++++++++++++++++++++++++------------- sysdeps/unix/sysv/linux/semctl.c | 7 +++++++ sysdeps/unix/sysv/linux/shmctl.c | 38 +++++++++++++++++++++++++------------- 4 files changed, 63 insertions(+), 26 deletions(-) diff --git a/sysdeps/unix/sysv/linux/ipc_priv.h b/sysdeps/unix/sysv/linux/ipc_priv.h index 87893a6757..2f50c31a8e 100644 --- a/sysdeps/unix/sysv/linux/ipc_priv.h +++ b/sysdeps/unix/sysv/linux/ipc_priv.h @@ -63,4 +63,10 @@ struct __old_ipc_perm # define __IPC_TIME64 0 #endif +#if __IPC_TIME64 || defined __ASSUME_SYSVIPC_BROKEN_MODE_T +# define IPC_CTL_NEED_TRANSLATION 1 +#else +# define IPC_CTL_NEED_TRANSLATION 0 +#endif + #include diff --git a/sysdeps/unix/sysv/linux/msgctl.c b/sysdeps/unix/sysv/linux/msgctl.c index e824ebb095..67b43c0eff 100644 --- a/sysdeps/unix/sysv/linux/msgctl.c +++ b/sysdeps/unix/sysv/linux/msgctl.c @@ -85,11 +85,19 @@ msgctl_syscall (int msqid, int cmd, msgctl_arg_t *buf) int __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf) { -#if __IPC_TIME64 +#if IPC_CTL_NEED_TRANSLATION +# if __IPC_TIME64 struct kernel_msqid64_ds ksemid, *arg = NULL; -#else +# else msgctl_arg_t *arg; -#endif +# endif + + /* Some applications pass the __IPC_64 flag in cmd, to invoke + previously unsupported commands back when there was no EINVAL + error checking in glibc. Mask the flag for the switch statements + below. ,sgctl_syscall adds back the __IPC_64 flag for the actual + system call. */ + cmd &= ~__IPC_64; switch (cmd) { @@ -101,19 +109,19 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf) case IPC_STAT: case MSG_STAT: case MSG_STAT_ANY: -#if __IPC_TIME64 +# if __IPC_TIME64 if (buf != NULL) { msqid64_to_kmsqid64 (buf, &ksemid); arg = &ksemid; } -# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T if (cmd == IPC_SET) arg->msg_perm.mode *= 0x10000U; -# endif -#else +# endif +# else arg = buf; -#endif +# endif break; case IPC_INFO: @@ -137,21 +145,25 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf) case IPC_STAT: case MSG_STAT: case MSG_STAT_ANY: -#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T arg->msg_perm.mode >>= 16; -#else +# else /* Old Linux kernel versions might not clear the mode padding. */ if (sizeof ((struct msqid_ds){0}.msg_perm.mode) != sizeof (__kernel_mode_t)) arg->msg_perm.mode &= 0xFFFF; -#endif +# endif -#if __IPC_TIME64 +# if __IPC_TIME64 kmsqid64_to_msqid64 (arg, buf); -#endif +# endif } return ret; + +#else /* !IPC_CTL_NEED_TRANSLATION */ + return msgctl_syscall (msqid, cmd, buf); +#endif } #if __TIMESIZE != 64 libc_hidden_def (__msgctl64) diff --git a/sysdeps/unix/sysv/linux/semctl.c b/sysdeps/unix/sysv/linux/semctl.c index 77a8130c18..3458b018bc 100644 --- a/sysdeps/unix/sysv/linux/semctl.c +++ b/sysdeps/unix/sysv/linux/semctl.c @@ -140,6 +140,13 @@ __semctl64 (int semid, int semnum, int cmd, ...) union semun64 arg64 = { 0 }; va_list ap; + /* Some applications pass the __IPC_64 flag in cmd, to invoke + previously unsupported commands back when there was no EINVAL + error checking in glibc. Mask the flag for the switch statements + below. semctl_syscall adds back the __IPC_64 flag for the actual + system call. */ + cmd &= ~__IPC_64; + /* Get the argument only if required. */ switch (cmd) { diff --git a/sysdeps/unix/sysv/linux/shmctl.c b/sysdeps/unix/sysv/linux/shmctl.c index ea38935497..f00817a6f6 100644 --- a/sysdeps/unix/sysv/linux/shmctl.c +++ b/sysdeps/unix/sysv/linux/shmctl.c @@ -85,11 +85,19 @@ shmctl_syscall (int shmid, int cmd, shmctl_arg_t *buf) int __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf) { -#if __IPC_TIME64 +#if IPC_CTL_NEED_TRANSLATION +# if __IPC_TIME64 struct kernel_shmid64_ds kshmid, *arg = NULL; -#else +# else shmctl_arg_t *arg; -#endif +# endif + + /* Some applications pass the __IPC_64 flag in cmd, to invoke + previously unsupported commands back when there was no EINVAL + error checking in glibc. Mask the flag for the switch statements + below. shmctl_syscall adds back the __IPC_64 flag for the actual + system call. */ + cmd &= ~__IPC_64; switch (cmd) { @@ -103,19 +111,19 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf) case IPC_STAT: case SHM_STAT: case SHM_STAT_ANY: -#if __IPC_TIME64 +# if __IPC_TIME64 if (buf != NULL) { shmid64_to_kshmid64 (buf, &kshmid); arg = &kshmid; } -# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T if (cmd == IPC_SET) arg->shm_perm.mode *= 0x10000U; -# endif -#else +# endif +# else arg = buf; -#endif +# endif break; case IPC_INFO: @@ -140,21 +148,25 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf) case IPC_STAT: case SHM_STAT: case SHM_STAT_ANY: -#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T arg->shm_perm.mode >>= 16; -#else +# else /* Old Linux kernel versions might not clear the mode padding. */ if (sizeof ((struct shmid_ds){0}.shm_perm.mode) != sizeof (__kernel_mode_t)) arg->shm_perm.mode &= 0xFFFF; -#endif +# endif -#if __IPC_TIME64 +# if __IPC_TIME64 kshmid64_to_shmid64 (arg, buf); -#endif +# endif } return ret; + +#else /* !IPC_CTL_NEED_TRANSLATION */ + return shmctl_syscall (shmid, cmd, buf); +#endif } #if __TIMESIZE != 64 libc_hidden_def (__shmctl64) base-commit: 19934d629ee22bbd332f04da4320e4f624c9560c