From e340db56483b6e10bd5e5f281071876808801a41 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Tue, 20 Mar 2018 20:15:28 +0100 Subject: [PATCH] ipc: add msgctl syscall/compat_syscall wrappers Provide ksys_msgctl() and compat_ksys_msgctl() 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_msgctl() and compat_sys_msgctl(). 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@light.dominikbrodowski.net Cc: Al Viro Cc: Andrew Morton Signed-off-by: Dominik Brodowski --- ipc/msg.c | 14 ++++++++++++-- ipc/syscall.c | 5 +++-- ipc/util.h | 2 ++ 3 files changed, 17 insertions(+), 4 deletions(-) diff --git a/ipc/msg.c b/ipc/msg.c index 64e8276be164..5b026868df07 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -538,7 +538,7 @@ static int msgctl_stat(struct ipc_namespace *ns, int msqid, return err; } -SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) +long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf) { int version; struct ipc_namespace *ns; @@ -581,6 +581,11 @@ SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) } } +SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) +{ + return ksys_msgctl(msqid, cmd, buf); +} + #ifdef CONFIG_COMPAT struct compat_msqid_ds { @@ -651,7 +656,7 @@ static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in, } } -COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr) +long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr) { struct ipc_namespace *ns; int err; @@ -692,6 +697,11 @@ COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr) return -EINVAL; } } + +COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr) +{ + return compat_ksys_msgctl(msqid, cmd, uptr); +} #endif static int testmsg(struct msg_msg *msg, long type, int mode) diff --git a/ipc/syscall.c b/ipc/syscall.c index 34bbabc9e672..aa29b0802e26 100644 --- a/ipc/syscall.c +++ b/ipc/syscall.c @@ -70,7 +70,8 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, case MSGGET: return ksys_msgget((key_t) first, second); case MSGCTL: - return sys_msgctl(first, second, (struct msqid_ds __user *)ptr); + return ksys_msgctl(first, second, + (struct msqid_ds __user *)ptr); case SHMAT: switch (version) { @@ -163,7 +164,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, case MSGGET: return ksys_msgget(first, second); case MSGCTL: - return compat_sys_msgctl(first, second, compat_ptr(ptr)); + return compat_ksys_msgctl(first, second, compat_ptr(ptr)); case SHMAT: { int err; diff --git a/ipc/util.h b/ipc/util.h index 16e8b5b8c416..47837b4af3f2 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -243,6 +243,7 @@ long ksys_semtimedop(int semid, struct sembuf __user *tsops, long ksys_semget(key_t key, int nsems, int semflg); long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg); long ksys_msgget(key_t key, int msgflg); +long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf); 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); @@ -253,6 +254,7 @@ 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); +long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr); long compat_ksys_shmctl(int shmid, int cmd, void __user *uptr); #endif /* CONFIG_COMPAT */ -- GitLab