projects / pve-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 321d628a FG |
1 | From d8fdea47d7fc1177aa0843a49dc89422ac6f4fea Mon Sep 17 00:00:00 2001 |
| 2 | From: Andy Lutomirski <luto@kernel.org> | |
| 3 | Date: Thu, 2 Nov 2017 00:59:02 -0700 | |
| e4cdf2a5 | 4 | Subject: [PATCH 090/241] x86/entry/64: Shrink paranoid_exit_restore and make |
| 321d628a FG |
5 | labels local |
| 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 | paranoid_exit_restore was a copy of restore_regs_and_return_to_kernel. | |
| 13 | Merge them and make the paranoid_exit internal labels local. | |
| 14 | ||
| 15 | Keeping .Lparanoid_exit makes the code a bit shorter because it | |
| 16 | allows a 2-byte jnz instead of a 5-byte jnz. | |
| 17 | ||
| 18 | Saves 96 bytes of text. | |
| 19 | ||
| 20 | ( This is still a bit suboptimal in a non-CONFIG_TRACE_IRQFLAGS | |
| 21 | kernel, but fixing that would make the code rather messy. ) | |
| 22 | ||
| 23 | Signed-off-by: Andy Lutomirski <luto@kernel.org> | |
| 24 | Cc: Borislav Petkov <bpetkov@suse.de> | |
| 25 | Cc: Brian Gerst <brgerst@gmail.com> | |
| 26 | Cc: Dave Hansen <dave.hansen@intel.com> | |
| 27 | Cc: Linus Torvalds <torvalds@linux-foundation.org> | |
| 28 | Cc: Peter Zijlstra <peterz@infradead.org> | |
| 29 | Cc: Thomas Gleixner <tglx@linutronix.de> | |
| 30 | Link: http://lkml.kernel.org/r/510d66a1895cda9473c84b1086f0bb974f22de6a.1509609304.git.luto@kernel.org | |
| 31 | Signed-off-by: Ingo Molnar <mingo@kernel.org> | |
| 32 | (cherry picked from commit e53178328c9b96fbdbc719e78c93b5687ee007c3) | |
| 33 | Signed-off-by: Andy Whitcroft <apw@canonical.com> | |
| 34 | Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> | |
| 35 | (cherry picked from commit fb53fe10add935c3d0eb63199e43426eaf3b4299) | |
| 36 | Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> | |
| 37 | --- | |
| 38 | arch/x86/entry/entry_64.S | 13 +++++-------- | |
| 39 | 1 file changed, 5 insertions(+), 8 deletions(-) | |
| 40 | ||
| 41 | diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S | |
| 42 | index a1a86e782a0e..6995f7e08aa1 100644 | |
| 43 | --- a/arch/x86/entry/entry_64.S | |
| 44 | +++ b/arch/x86/entry/entry_64.S | |
| 45 | @@ -1136,17 +1136,14 @@ ENTRY(paranoid_exit) | |
| 46 | DISABLE_INTERRUPTS(CLBR_ANY) | |
| 47 | TRACE_IRQS_OFF_DEBUG | |
| 48 | testl %ebx, %ebx /* swapgs needed? */ | |
| 49 | - jnz paranoid_exit_no_swapgs | |
| 50 | + jnz .Lparanoid_exit_no_swapgs | |
| 51 | TRACE_IRQS_IRETQ | |
| 52 | SWAPGS_UNSAFE_STACK | |
| 53 | - jmp paranoid_exit_restore | |
| 54 | -paranoid_exit_no_swapgs: | |
| 55 | + jmp .Lparanoid_exit_restore | |
| 56 | +.Lparanoid_exit_no_swapgs: | |
| 57 | TRACE_IRQS_IRETQ_DEBUG | |
| 58 | -paranoid_exit_restore: | |
| 59 | - RESTORE_EXTRA_REGS | |
| 60 | - RESTORE_C_REGS | |
| 61 | - REMOVE_PT_GPREGS_FROM_STACK 8 | |
| 62 | - INTERRUPT_RETURN | |
| 63 | +.Lparanoid_exit_restore: | |
| 64 | + jmp restore_regs_and_return_to_kernel | |
| 65 | END(paranoid_exit) | |
| 66 | ||
| 67 | /* | |
| 68 | -- | |
| 69 | 2.14.2 | |
| 70 |