forked from Minki/linux
b485342bd7
Commita074335a37("x86, um: Mark system call tables readonly") was supposed to mark the sys_call_table in UML as RO by adding the const, but it doesn't have the desired effect as it's nevertheless being placed into the data section since __cacheline_aligned enforces sys_call_table being placed into .data..cacheline_aligned instead. We need to use the ____cacheline_aligned version instead to fix this issue. Before: $ nm -v arch/x86/um/sys_call_table_64.o | grep -1 "sys_call_table" U sys_writev 0000000000000000 D sys_call_table 0000000000000000 D syscall_table_size After: $ nm -v arch/x86/um/sys_call_table_64.o | grep -1 "sys_call_table" U sys_writev 0000000000000000 R sys_call_table 0000000000000000 D syscall_table_size Fixes:a074335a37("x86, um: Mark system call tables readonly") Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Richard Weinberger <richard@nod.at>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/*
|
|
* System call table for UML/i386, copied from arch/x86/kernel/syscall_*.c
|
|
* with some changes for UML.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <linux/sys.h>
|
|
#include <linux/cache.h>
|
|
#include <generated/user_constants.h>
|
|
|
|
#define __NO_STUBS
|
|
|
|
/*
|
|
* Below you can see, in terms of #define's, the differences between the x86-64
|
|
* and the UML syscall table.
|
|
*/
|
|
|
|
/* Not going to be implemented by UML, since we have no hardware. */
|
|
#define sys_iopl sys_ni_syscall
|
|
#define sys_ioperm sys_ni_syscall
|
|
|
|
#define sys_vm86old sys_ni_syscall
|
|
#define sys_vm86 sys_ni_syscall
|
|
|
|
#define old_mmap sys_old_mmap
|
|
|
|
#define __SYSCALL_I386(nr, sym, compat) extern asmlinkage void sym(void) ;
|
|
#include <asm/syscalls_32.h>
|
|
|
|
#undef __SYSCALL_I386
|
|
#define __SYSCALL_I386(nr, sym, compat) [ nr ] = sym,
|
|
|
|
typedef asmlinkage void (*sys_call_ptr_t)(void);
|
|
|
|
extern asmlinkage void sys_ni_syscall(void);
|
|
|
|
const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = {
|
|
/*
|
|
* Smells like a compiler bug -- it doesn't work
|
|
* when the & below is removed.
|
|
*/
|
|
[0 ... __NR_syscall_max] = &sys_ni_syscall,
|
|
#include <asm/syscalls_32.h>
|
|
};
|
|
|
|
int syscall_table_size = sizeof(sys_call_table);
|