diff options
| author | Ben Hutchings <ben.hutchings@codethink.co.uk> | 2018-01-26 16:23:02 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-31 12:06:12 +0100 |
| commit | ed73df0b7f23c95b3243a0f4bfc40f962e61d349 (patch) | |
| tree | 811103f316f159d85279570adebc495a882b8821 /arch | |
| parent | e1e457a49544718928282c56b69af082e1ebe405 (diff) | |
vsyscall: Fix permissions for emulate mode with KAISER/PTI
The backport of KAISER to 4.4 turned vsyscall emulate mode into native
mode. Add a vsyscall_pgprot variable to hold the correct page
protections, like Borislav and Hugh did for 3.2 and 3.18.
Cc: Borislav Petkov <bp@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/entry/vsyscall/vsyscall_64.c | 7 | ||||
| -rw-r--r-- | arch/x86/include/asm/vsyscall.h | 1 | ||||
| -rw-r--r-- | arch/x86/mm/kaiser.c | 2 |
3 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 112178b401a1..2d359991a273 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -46,6 +46,7 @@ static enum { EMULATE, NATIVE, NONE } vsyscall_mode = #else EMULATE; #endif +unsigned long vsyscall_pgprot = __PAGE_KERNEL_VSYSCALL; static int __init vsyscall_setup(char *str) { @@ -336,11 +337,11 @@ void __init map_vsyscall(void) extern char __vsyscall_page; unsigned long physaddr_vsyscall = __pa_symbol(&__vsyscall_page); + if (vsyscall_mode != NATIVE) + vsyscall_pgprot = __PAGE_KERNEL_VVAR; if (vsyscall_mode != NONE) __set_fixmap(VSYSCALL_PAGE, physaddr_vsyscall, - vsyscall_mode == NATIVE - ? PAGE_KERNEL_VSYSCALL - : PAGE_KERNEL_VVAR); + __pgprot(vsyscall_pgprot)); BUILD_BUG_ON((unsigned long)__fix_to_virt(VSYSCALL_PAGE) != (unsigned long)VSYSCALL_ADDR); diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h index 4865e10dbb55..9ee85066f407 100644 --- a/arch/x86/include/asm/vsyscall.h +++ b/arch/x86/include/asm/vsyscall.h @@ -13,6 +13,7 @@ extern void map_vsyscall(void); */ extern bool emulate_vsyscall(struct pt_regs *regs, unsigned long address); extern bool vsyscall_enabled(void); +extern unsigned long vsyscall_pgprot; #else static inline void map_vsyscall(void) {} static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c index 8af98513d36c..2298434f7bdb 100644 --- a/arch/x86/mm/kaiser.c +++ b/arch/x86/mm/kaiser.c @@ -345,7 +345,7 @@ void __init kaiser_init(void) if (vsyscall_enabled()) kaiser_add_user_map_early((void *)VSYSCALL_ADDR, PAGE_SIZE, - __PAGE_KERNEL_VSYSCALL); + vsyscall_pgprot); for_each_possible_cpu(cpu) { void *percpu_vaddr = __per_cpu_user_mapped_start + |