Provide ksys_msgsnd() and compat_ksys_msgsnd() 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_msgsnd() and compat_sys_msgsnd(). 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/msg.c | 20 ++++++++++++++++---- ipc/syscall.c | 4 ++-- ipc/util.h | 4 ++++ 3 files changed, 22 insertions(+), 6 deletions(-) diff --git a/ipc/msg.c b/ipc/msg.c index abc5826270a6..9de48065c1ac 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -867,8 +867,8 @@ static long do_msgsnd(int msqid, long mtype, void __user *mtext, return err; } -SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, - int, msgflg) +long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz, + int msgflg) { long mtype; @@ -877,6 +877,12 @@ SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg); } +SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, + int, msgflg) +{ + return ksys_msgsnd(msqid, msgp, msgsz, msgflg); +} + #ifdef CONFIG_COMPAT struct compat_msgbuf { @@ -884,8 +890,8 @@ struct compat_msgbuf { char mtext[1]; }; -COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp, - compat_ssize_t, msgsz, int, msgflg) +long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp, + compat_ssize_t msgsz, int msgflg) { struct compat_msgbuf __user *up = compat_ptr(msgp); compat_long_t mtype; @@ -894,6 +900,12 @@ COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp, return -EFAULT; return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg); } + +COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp, + compat_ssize_t, msgsz, int, msgflg) +{ + return compat_ksys_msgsnd(msqid, msgp, msgsz, msgflg); +} #endif static inline int convert_mode(long *msgtyp, int msgflg) diff --git a/ipc/syscall.c b/ipc/syscall.c index 0228c7afd882..77a883ef2eca 100644 --- a/ipc/syscall.c +++ b/ipc/syscall.c @@ -46,7 +46,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, } case MSGSND: - return sys_msgsnd(first, (struct msgbuf __user *) ptr, + return ksys_msgsnd(first, (struct msgbuf __user *) ptr, second, third); case MSGRCV: switch (version) { @@ -142,7 +142,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, return compat_ksys_semctl(first, second, third, pad); case MSGSND: - return compat_sys_msgsnd(first, ptr, second, third); + return compat_ksys_msgsnd(first, ptr, second, third); case MSGRCV: { void __user *uptr = compat_ptr(ptr); diff --git a/ipc/util.h b/ipc/util.h index c16aceb1bdec..51853dc2f340 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -246,6 +246,8 @@ long ksys_msgget(key_t key, int msgflg); long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf); long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz, long msgtyp, int msgflg); +long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz, + int msgflg); long ksys_shmget(key_t key, size_t size, int shmflg); long ksys_shmdt(char __user *shmaddr); long ksys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf); @@ -259,6 +261,8 @@ long compat_ksys_semctl(int semid, int semnum, int cmd, int arg); long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr); long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz, compat_long_t msgtyp, int msgflg); +long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp, + compat_ssize_t msgsz, int msgflg); long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr); #endif /* CONFIG_COMPAT */ -- 2.16.3
