Provide ksys_semctl() and compat_ksys_semctl() wrappers to avoid in-kernel calls to these syscalls. The ksys_ prefix denotes that these functions are meant as a drop-in replacement for the syscalls. In particular, they use the same calling convention as sys_semctl() and compat_sys_semctl(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@xxxxxxxxxxxxxxxxxxxxxxxxxx Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx> --- ipc/sem.c | 14 ++++++++++++-- ipc/syscall.c | 4 ++-- ipc/util.h | 2 ++ 3 files changed, 16 insertions(+), 4 deletions(-) diff --git a/ipc/sem.c b/ipc/sem.c index 2e5f7ec7a7db..1cf56279a84c 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -1581,7 +1581,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, return err; } -SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) +long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg) { int version; struct ipc_namespace *ns; @@ -1635,6 +1635,11 @@ SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) } } +SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) +{ + return ksys_semctl(semid, semnum, cmd, arg); +} + #ifdef CONFIG_COMPAT struct compat_semid_ds { @@ -1683,7 +1688,7 @@ static int copy_compat_semid_to_user(void __user *buf, struct semid64_ds *in, } } -COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg) +long compat_ksys_semctl(int semid, int semnum, int cmd, int arg) { void __user *p = compat_ptr(arg); struct ipc_namespace *ns; @@ -1727,6 +1732,11 @@ COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg) return -EINVAL; } } + +COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg) +{ + return compat_ksys_semctl(semid, semnum, cmd, arg); +} #endif /* If the task doesn't already have a undo_list, then allocate one diff --git a/ipc/syscall.c b/ipc/syscall.c index 21fcdf0b4836..a536cca37661 100644 --- a/ipc/syscall.c +++ b/ipc/syscall.c @@ -42,7 +42,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, return -EINVAL; if (get_user(arg, (unsigned long __user *) ptr)) return -EFAULT; - return sys_semctl(first, second, third, arg); + return ksys_semctl(first, second, third, arg); } case MSGSND: @@ -138,7 +138,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, return -EINVAL; if (get_user(pad, (u32 __user *) compat_ptr(ptr))) return -EFAULT; - return compat_sys_semctl(first, second, third, pad); + return compat_ksys_semctl(first, second, third, pad); case MSGSND: return compat_sys_msgsnd(first, ptr, second, third); diff --git a/ipc/util.h b/ipc/util.h index 0f07056e5a73..1f1109b83437 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -241,12 +241,14 @@ long ksys_semtimedop(int semid, struct sembuf __user *tsops, unsigned int nsops, const struct timespec __user *timeout); long ksys_semget(key_t key, int nsems, int semflg); +long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg); /* for CONFIG_ARCH_WANT_OLD_COMPAT_IPC */ #ifdef CONFIG_COMPAT long compat_ksys_semtimedop(int semid, struct sembuf __user *tsems, unsigned int nsops, const struct compat_timespec __user *timeout); +long compat_ksys_semctl(int semid, int semnum, int cmd, int arg); #endif /* CONFIG_COMPAT */ #endif -- 2.16.3
