diff options
-rw-r--r-- | arch/x86/kernel/ldt.c | 4 | ||||
-rw-r--r-- | arch/x86/vdso/vdso32-setup.c | 8 |
2 files changed, 11 insertions, 1 deletions
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c index af1d14a9ebda..dcbbaa165bde 100644 --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -20,6 +20,8 @@ #include <asm/mmu_context.h> #include <asm/syscalls.h> +int sysctl_ldt16 = 0; + #ifdef CONFIG_SMP static void flush_ldt(void *current_mm) { @@ -234,7 +236,7 @@ static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode) * IRET leaking the high bits of the kernel stack address. */ #ifdef CONFIG_X86_64 - if (!ldt_info.seg_32bit) { + if (!ldt_info.seg_32bit && !sysctl_ldt16) { error = -EINVAL; goto out_unlock; } diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c index 00348980a3a6..e1f220e3ca68 100644 --- a/arch/x86/vdso/vdso32-setup.c +++ b/arch/x86/vdso/vdso32-setup.c @@ -39,6 +39,7 @@ #ifdef CONFIG_X86_64 #define vdso_enabled sysctl_vsyscall32 #define arch_setup_additional_pages syscall32_setup_pages +extern int sysctl_ldt16; #endif /* @@ -249,6 +250,13 @@ static struct ctl_table abi_table2[] = { .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "ldt16", + .data = &sysctl_ldt16, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, {} }; |