path: root/ipc
diff options
authorDominik Brodowski <>2018-03-20 20:09:48 +0100
committerDominik Brodowski <>2018-04-02 20:15:25 +0200
commitda1e2744341542e404c172bcf6a321f509408b14 (patch)
treee2404117362bb519750e1f18b4d513c1958fab1b /ipc
parent65749e0bb5e7de876ee43d3f601e32afe17e9248 (diff)
ipc: add shmdt syscall wrapper
Provide ksys_shmdt() 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_shmdt(). 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 Cc: Al Viro <> Cc: Andrew Morton <> Signed-off-by: Dominik Brodowski <>
Diffstat (limited to 'ipc')
3 files changed, 9 insertions, 3 deletions
diff --git a/ipc/shm.c b/ipc/shm.c
index 9f3cdb2..e5838e3 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1481,7 +1481,7 @@ COMPAT_SYSCALL_DEFINE3(shmat, int, shmid, compat_uptr_t, shmaddr, int, shmflg)
* detach and kill segment if marked destroyed.
* The work is done in shm_close.
-SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
+long ksys_shmdt(char __user *shmaddr)
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
@@ -1588,6 +1588,11 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
return retval;
+SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
+ return ksys_shmdt(shmaddr);
static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
diff --git a/ipc/syscall.c b/ipc/syscall.c
index 60bceb1..b3aa715 100644
--- a/ipc/syscall.c
+++ b/ipc/syscall.c
@@ -90,7 +90,7 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
return -EINVAL;
case SHMDT:
- return sys_shmdt((char __user *)ptr);
+ return ksys_shmdt((char __user *)ptr);
case SHMGET:
return ksys_shmget(first, second, third);
case SHMCTL:
@@ -178,7 +178,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
return put_user(raddr, (compat_ulong_t __user *)compat_ptr(third));
case SHMDT:
- return sys_shmdt(compat_ptr(ptr));
+ return ksys_shmdt(compat_ptr(ptr));
case SHMGET:
return ksys_shmget(first, (unsigned int)second, third);
case SHMCTL:
diff --git a/ipc/util.h b/ipc/util.h
index 51002c0b..7770bca 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -244,6 +244,7 @@ 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_shmget(key_t key, size_t size, int shmflg);
+long ksys_shmdt(char __user *shmaddr);
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