From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2178) id E59C33858CDA; Thu, 10 Nov 2022 13:23:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E59C33858CDA DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1668086606; bh=/NG2AgrLL9ke+ja70wwOxkKpfYM5OrHsdUUWzVbYfNE=; h=From:To:Subject:Date:From; b=yxsGv0VS04/Y2oe77Tw2bIHyNRiKtQZ3LAJpf/SAIOlLur91sZU8AvsRFCXWl5hJ1 z9c7xVTA9IiLE5+dfBfwaWyzRCnUC9/nUZ5SfZeYKKkLoNvw17CClMNLGBtIVcqCf7 /9WZa/Wm7e9PQ3+3bMS9izeAQhEFkk02GgZ2ssC8= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Florian Weimer To: glibc-cvs@sourceware.org Subject: [glibc] Linux: Support __IPC_64 in sysvctl *ctl command arguments (bug 29771) X-Act-Checkin: glibc X-Git-Author: Florian Weimer X-Git-Refname: refs/heads/master X-Git-Oldrev: 38caf7a1cc92e6a546ea655701c8237ee727d0d3 X-Git-Newrev: 22a46dee24351fd5f4f188ad80554cad79c82524 Message-Id: <20221110132326.E59C33858CDA@sourceware.org> Date: Thu, 10 Nov 2022 13:23:26 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=22a46dee24351fd5f4f188ad80554cad79c82524 commit 22a46dee24351fd5f4f188ad80554cad79c82524 Author: Florian Weimer Date: Tue Nov 8 14:15:02 2022 +0100 Linux: Support __IPC_64 in sysvctl *ctl command arguments (bug 29771) 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. Reviewed-by: Adhemerval Zanella Diff: --- 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..2072205252 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. msgctl_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)