From 275f22148e8720e84b180d9e0cdf8abfd69bac5b Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 31 Dec 2018 22:22:40 +0100 Subject: ipc: rename old-style shmctl/semctl/msgctl syscalls The behavior of these system calls is slightly different between architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION symbol. Most architectures that implement the split IPC syscalls don't set that symbol and only get the modern version, but alpha, arm, microblaze, mips-n32, mips-n64 and xtensa expect the caller to pass the IPC_64 flag. For the architectures that so far only implement sys_ipc(), i.e. m68k, mips-o32, powerpc, s390, sh, sparc, and x86-32, we want the new behavior when adding the split syscalls, so we need to distinguish between the two groups of architectures. The method I picked for this distinction is to have a separate system call entry point: sys_old_*ctl() now uses ipc_parse_version, while sys_*ctl() does not. The system call tables of the five architectures are changed accordingly. As an additional benefit, we no longer need the configuration specific definition for ipc_parse_version(), it always does the same thing now, but simply won't get called on architectures with the modern interface. A small downside is that on architectures that do set ARCH_WANT_IPC_PARSE_VERSION, we now have an extra set of entry points that are never called. They only add a few bytes of bloat, so it seems better to keep them compared to adding yet another Kconfig symbol. I considered adding new syscall numbers for the IPC_64 variants for consistency, but decided against that for now. Signed-off-by: Arnd Bergmann --- ipc/shm.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) (limited to 'ipc/shm.c') diff --git a/ipc/shm.c b/ipc/shm.c index 0842411cb0e9..ce1ca9f7c6e9 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -1137,16 +1137,15 @@ out_unlock1: return err; } -long ksys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf) +static long ksys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf, int version) { - int err, version; + int err; struct ipc_namespace *ns; struct shmid64_ds sem64; if (cmd < 0 || shmid < 0) return -EINVAL; - version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch (cmd) { @@ -1194,8 +1193,22 @@ long ksys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf) SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) { - return ksys_shmctl(shmid, cmd, buf); + return ksys_shmctl(shmid, cmd, buf, IPC_64); +} + +#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION +long ksys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf) +{ + int version = ipc_parse_version(&cmd); + + return ksys_shmctl(shmid, cmd, buf, version); +} + +SYSCALL_DEFINE3(old_shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) +{ + return ksys_old_shmctl(shmid, cmd, buf); } +#endif #ifdef CONFIG_COMPAT @@ -1319,11 +1332,10 @@ static int copy_compat_shmid_from_user(struct shmid64_ds *out, void __user *buf, } } -long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr) +long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr, int version) { struct ipc_namespace *ns; struct shmid64_ds sem64; - int version = compat_ipc_parse_version(&cmd); int err; ns = current->nsproxy->ipc_ns; @@ -1378,8 +1390,22 @@ long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr) COMPAT_SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, void __user *, uptr) { - return compat_ksys_shmctl(shmid, cmd, uptr); + return compat_ksys_shmctl(shmid, cmd, uptr, IPC_64); } + +#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION +long compat_ksys_old_shmctl(int shmid, int cmd, void __user *uptr) +{ + int version = compat_ipc_parse_version(&cmd); + + return compat_ksys_shmctl(shmid, cmd, uptr, version); +} + +COMPAT_SYSCALL_DEFINE3(old_shmctl, int, shmid, int, cmd, void __user *, uptr) +{ + return compat_ksys_old_shmctl(shmid, cmd, uptr); +} +#endif #endif /* -- cgit v1.2.3