projects / pve-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 321d628a FG |
1 | From c48697564de6da427f1e97a38192f4d456223942 Mon Sep 17 00:00:00 2001 |
| 2 | From: Andy Lutomirski <luto@kernel.org> | |
| 3 | Date: Thu, 2 Nov 2017 00:59:04 -0700 | |
| e4cdf2a5 | 4 | Subject: [PATCH 092/241] x86/entry/64: Merge the fast and slow SYSRET paths |
| 321d628a FG |
5 | MIME-Version: 1.0 |
| 6 | Content-Type: text/plain; charset=UTF-8 | |
| 7 | Content-Transfer-Encoding: 8bit | |
| 8 | ||
| 9 | CVE-2017-5754 | |
| 10 | ||
| 11 | They did almost the same thing. Remove a bunch of pointless | |
| 12 | instructions (mostly hidden in macros) and reduce cognitive load by | |
| 13 | merging them. | |
| 14 | ||
| 15 | Signed-off-by: Andy Lutomirski <luto@kernel.org> | |
| 16 | Cc: Borislav Petkov <bpetkov@suse.de> | |
| 17 | Cc: Brian Gerst <brgerst@gmail.com> | |
| 18 | Cc: Dave Hansen <dave.hansen@intel.com> | |
| 19 | Cc: Linus Torvalds <torvalds@linux-foundation.org> | |
| 20 | Cc: Peter Zijlstra <peterz@infradead.org> | |
| 21 | Cc: Thomas Gleixner <tglx@linutronix.de> | |
| 22 | Link: http://lkml.kernel.org/r/1204e20233fcab9130a1ba80b3b1879b5db3fc1f.1509609304.git.luto@kernel.org | |
| 23 | Signed-off-by: Ingo Molnar <mingo@kernel.org> | |
| 24 | (cherry picked from commit a512210643da8082cb44181dba8b18e752bd68f0) | |
| 25 | Signed-off-by: Andy Whitcroft <apw@canonical.com> | |
| 26 | Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> | |
| 27 | (cherry picked from commit 7c4575d8bb2d01960ba9b9840fa22460e0179eca) | |
| 28 | Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> | |
| 29 | --- | |
| 30 | arch/x86/entry/entry_64.S | 6 +++--- | |
| 31 | 1 file changed, 3 insertions(+), 3 deletions(-) | |
| 32 | ||
| 33 | diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S | |
| 34 | index 33a416c7df2d..87be1cd1fa88 100644 | |
| 35 | --- a/arch/x86/entry/entry_64.S | |
| 36 | +++ b/arch/x86/entry/entry_64.S | |
| 37 | @@ -220,10 +220,9 @@ entry_SYSCALL_64_fastpath: | |
| 38 | TRACE_IRQS_ON /* user mode is traced as IRQs on */ | |
| 39 | movq RIP(%rsp), %rcx | |
| 40 | movq EFLAGS(%rsp), %r11 | |
| 41 | - RESTORE_C_REGS_EXCEPT_RCX_R11 | |
| 42 | - movq RSP(%rsp), %rsp | |
| 43 | + addq $6*8, %rsp /* skip extra regs -- they were preserved */ | |
| 44 | UNWIND_HINT_EMPTY | |
| 45 | - USERGS_SYSRET64 | |
| 46 | + jmp .Lpop_c_regs_except_rcx_r11_and_sysret | |
| 47 | ||
| 48 | 1: | |
| 49 | /* | |
| 50 | @@ -317,6 +316,7 @@ syscall_return_via_sysret: | |
| 51 | /* rcx and r11 are already restored (see code above) */ | |
| 52 | UNWIND_HINT_EMPTY | |
| 53 | POP_EXTRA_REGS | |
| 54 | +.Lpop_c_regs_except_rcx_r11_and_sysret: | |
| 55 | popq %rsi /* skip r11 */ | |
| 56 | popq %r10 | |
| 57 | popq %r9 | |
| 58 | -- | |
| 59 | 2.14.2 | |
| 60 |