When the ipc system call is used to wrap a semctl system call,
the ptr argument to ipc needs to be dereferenced prior to passing
it to the semctl handler. This is because the fourth argument to
semctl is a union and not a pointer to a union.
Signed-off-by: Tom Musta <tommu...@gmail.com>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 540001c..229c482 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3135,9 +3135,15 @@ static abi_long do_ipc(unsigned int call, int first,
ret = get_errno(semget(first, second, third));
break;
- case IPCOP_semctl:
- ret = do_semctl(first, second, third, (union target_semun)(abi_ulong)
ptr);
+ case IPCOP_semctl: {
+ /* The semun argument to semctl is passed by value, so dereference the
+ * ptr argument. */
+ abi_ulong atptr;
+ get_user_ual(atptr, (abi_ulong)ptr);
+ ret = do_semctl(first, second, third,
+ (union target_semun)(abi_ulong) atptr);
break;
+ }
case IPCOP_msgget:
ret = get_errno(msgget(first, second));
--
1.7.1
