Commit-ID: 287e013108a104e459e675432cf20087feab2b67 Gitweb: http://git.kernel.org/tip/287e013108a104e459e675432cf20087feab2b67 Author: Andy Lutomirski <luto@xxxxxxxxxxxxxx> AuthorDate: Tue, 23 Sep 2014 10:50:55 -0700 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Tue, 28 Oct 2014 11:22:12 +0100 x86/vdso: Make the PER_CPU segment 32 bits IMO users ought not to be able to use 16-bit segments without using modify_ldt. Fortunately, it's impossible to break espfix64 by loading the PER_CPU segment into SS because it's PER_CPU is marked read-only and SS cannot contain an RO segment, but marking PER_CPU as 32-bit is less fragile. Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/179f490d659307873eefd09206bebd417e2ab5ad.1411494540.git.luto@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/vdso/vma.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index 0c799746..32ca60c 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -268,6 +268,7 @@ static void vsyscall_set_cpu(int cpu) .dpl = 3, /* Visible to user code */ .s = 1, /* Not a system segment */ .p = 1, /* Present */ + .d = 1, /* 32-bit */ }; write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
|