Provide ksys_semget() wrapper to avoid in-kernel calls to this syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_semget(). 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 | 7 ++++++- ipc/syscall.c | 4 ++-- ipc/util.h | 1 + 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/ipc/sem.c b/ipc/sem.c index e21ceb8b4af1..2e5f7ec7a7db 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -556,7 +556,7 @@ static inline int sem_more_checks(struct kern_ipc_perm *ipcp, return 0; } -SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) +long ksys_semget(key_t key, int nsems, int semflg) { struct ipc_namespace *ns; static const struct ipc_ops sem_ops = { @@ -578,6 +578,11 @@ SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params); } +SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) +{ + return ksys_semget(key, nsems, semflg); +} + /** * perform_atomic_semop[_slow] - Attempt to perform semaphore * operations on a given array. diff --git a/ipc/syscall.c b/ipc/syscall.c index 84d6a7691baa..21fcdf0b4836 100644 --- a/ipc/syscall.c +++ b/ipc/syscall.c @@ -35,7 +35,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, (const struct timespec __user *)fifth); case SEMGET: - return sys_semget(first, second, third); + return ksys_semget(first, second, third); case SEMCTL: { unsigned long arg; if (!ptr) @@ -132,7 +132,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, return compat_ksys_semtimedop(first, compat_ptr(ptr), second, compat_ptr(fifth)); case SEMGET: - return sys_semget(first, second, third); + return ksys_semget(first, second, third); case SEMCTL: if (!ptr) return -EINVAL; diff --git a/ipc/util.h b/ipc/util.h index 6deadf77547e..0f07056e5a73 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -240,6 +240,7 @@ static inline int compat_ipc_parse_version(int *cmd) 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); /* for CONFIG_ARCH_WANT_OLD_COMPAT_IPC */ #ifdef CONFIG_COMPAT -- 2.16.3
