]>
Commit | Line | Data |
---|---|---|
321d628a FG |
1 | From e8354b2be6f97e97515021452082436cec8857ea Mon Sep 17 00:00:00 2001 |
2 | From: Andy Lutomirski <luto@kernel.org> | |
3 | Date: Sun, 10 Dec 2017 22:47:20 -0800 | |
b378f209 | 4 | Subject: [PATCH 167/233] x86/vsyscall/64: Warn and fail vsyscall emulation in |
321d628a FG |
5 | NATIVE mode |
6 | MIME-Version: 1.0 | |
7 | Content-Type: text/plain; charset=UTF-8 | |
8 | Content-Transfer-Encoding: 8bit | |
9 | ||
10 | CVE-2017-5754 | |
11 | ||
12 | If something goes wrong with pagetable setup, vsyscall=native will | |
13 | accidentally fall back to emulation. Make it warn and fail so that we | |
14 | notice. | |
15 | ||
16 | Signed-off-by: Andy Lutomirski <luto@kernel.org> | |
17 | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> | |
18 | Cc: Borislav Petkov <bp@alien8.de> | |
19 | Cc: Brian Gerst <brgerst@gmail.com> | |
20 | Cc: Dave Hansen <dave.hansen@linux.intel.com> | |
21 | Cc: David Laight <David.Laight@aculab.com> | |
22 | Cc: H. Peter Anvin <hpa@zytor.com> | |
23 | Cc: Josh Poimboeuf <jpoimboe@redhat.com> | |
24 | Cc: Juergen Gross <jgross@suse.com> | |
25 | Cc: Kees Cook <keescook@chromium.org> | |
26 | Cc: Linus Torvalds <torvalds@linux-foundation.org> | |
27 | Cc: Peter Zijlstra <peterz@infradead.org> | |
28 | Signed-off-by: Ingo Molnar <mingo@kernel.org> | |
29 | (cherry picked from commit 4831b779403a836158917d59a7ca880483c67378) | |
30 | Signed-off-by: Andy Whitcroft <apw@canonical.com> | |
31 | Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> | |
32 | (cherry picked from commit ba10c7488b12c3106d79c8b2ba3f4e79c7e40ee4) | |
33 | Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> | |
34 | --- | |
35 | arch/x86/entry/vsyscall/vsyscall_64.c | 4 ++++ | |
36 | 1 file changed, 4 insertions(+) | |
37 | ||
38 | diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c | |
39 | index 91f3133cf5f1..5e56a4ced848 100644 | |
40 | --- a/arch/x86/entry/vsyscall/vsyscall_64.c | |
41 | +++ b/arch/x86/entry/vsyscall/vsyscall_64.c | |
42 | @@ -138,6 +138,10 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) | |
43 | ||
44 | WARN_ON_ONCE(address != regs->ip); | |
45 | ||
46 | + /* This should be unreachable in NATIVE mode. */ | |
47 | + if (WARN_ON(vsyscall_mode == NATIVE)) | |
48 | + return false; | |
49 | + | |
50 | if (vsyscall_mode == NONE) { | |
51 | warn_bad_vsyscall(KERN_INFO, regs, | |
52 | "vsyscall attempted with vsyscall=none"); | |
53 | -- | |
54 | 2.14.2 | |
55 |