projects / pve-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 321d628a FG |
1 | From b153f8e687bf0739b113445d3cfe029593e9484a Mon Sep 17 00:00:00 2001 |
| 2 | From: Andy Lutomirski <luto@kernel.org> | |
| 3 | Date: Mon, 4 Dec 2017 15:07:27 +0100 | |
| e4cdf2a5 | 4 | Subject: [PATCH 157/241] x86/entry/64: Remove the SYSENTER stack canary |
| 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 | Now that the SYSENTER stack has a guard page, there's no need for a canary | |
| 12 | to detect overflow after the fact. | |
| 13 | ||
| 14 | Signed-off-by: Andy Lutomirski <luto@kernel.org> | |
| 15 | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> | |
| 16 | Reviewed-by: Thomas Gleixner <tglx@linutronix.de> | |
| 17 | Reviewed-by: Borislav Petkov <bp@suse.de> | |
| 18 | Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> | |
| 19 | Cc: Borislav Petkov <bp@alien8.de> | |
| 20 | Cc: Borislav Petkov <bpetkov@suse.de> | |
| 21 | Cc: Brian Gerst <brgerst@gmail.com> | |
| 22 | Cc: Dave Hansen <dave.hansen@intel.com> | |
| 23 | Cc: Dave Hansen <dave.hansen@linux.intel.com> | |
| 24 | Cc: David Laight <David.Laight@aculab.com> | |
| 25 | Cc: Denys Vlasenko <dvlasenk@redhat.com> | |
| 26 | Cc: Eduardo Valentin <eduval@amazon.com> | |
| 27 | Cc: Greg KH <gregkh@linuxfoundation.org> | |
| 28 | Cc: H. Peter Anvin <hpa@zytor.com> | |
| 29 | Cc: Josh Poimboeuf <jpoimboe@redhat.com> | |
| 30 | Cc: Juergen Gross <jgross@suse.com> | |
| 31 | Cc: Linus Torvalds <torvalds@linux-foundation.org> | |
| 32 | Cc: Peter Zijlstra <peterz@infradead.org> | |
| 33 | Cc: Rik van Riel <riel@redhat.com> | |
| 34 | Cc: Will Deacon <will.deacon@arm.com> | |
| 35 | Cc: aliguori@amazon.com | |
| 36 | Cc: daniel.gruss@iaik.tugraz.at | |
| 37 | Cc: hughd@google.com | |
| 38 | Cc: keescook@google.com | |
| 39 | Link: https://lkml.kernel.org/r/20171204150606.572577316@linutronix.de | |
| 40 | Signed-off-by: Ingo Molnar <mingo@kernel.org> | |
| 41 | (cherry picked from commit 7fbbd5cbebf118a9e09f5453f686656a167c3d1c) | |
| 42 | Signed-off-by: Andy Whitcroft <apw@canonical.com> | |
| 43 | Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> | |
| 44 | (cherry picked from commit 8158adf795cb48be67891feacacc36d7a247afdf) | |
| 45 | Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> | |
| 46 | --- | |
| 47 | arch/x86/include/asm/processor.h | 1 - | |
| 48 | arch/x86/kernel/dumpstack.c | 3 +-- | |
| 49 | arch/x86/kernel/process.c | 1 - | |
| 50 | arch/x86/kernel/traps.c | 7 ------- | |
| 51 | 4 files changed, 1 insertion(+), 11 deletions(-) | |
| 52 | ||
| 53 | diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h | |
| 54 | index 1bfe4bad797a..4737d378d7b5 100644 | |
| 55 | --- a/arch/x86/include/asm/processor.h | |
| 56 | +++ b/arch/x86/include/asm/processor.h | |
| 57 | @@ -335,7 +335,6 @@ struct tss_struct { | |
| 58 | * Space for the temporary SYSENTER stack, used for SYSENTER | |
| 59 | * and the entry trampoline as well. | |
| 60 | */ | |
| 61 | - unsigned long SYSENTER_stack_canary; | |
| 62 | unsigned long SYSENTER_stack[64]; | |
| 63 | ||
| 64 | /* | |
| 65 | diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c | |
| 66 | index c1f503673f1e..c32c6cce9dcc 100644 | |
| 67 | --- a/arch/x86/kernel/dumpstack.c | |
| 68 | +++ b/arch/x86/kernel/dumpstack.c | |
| 69 | @@ -48,8 +48,7 @@ bool in_sysenter_stack(unsigned long *stack, struct stack_info *info) | |
| 70 | int cpu = smp_processor_id(); | |
| 71 | struct tss_struct *tss = &get_cpu_entry_area(cpu)->tss; | |
| 72 | ||
| 73 | - /* Treat the canary as part of the stack for unwinding purposes. */ | |
| 74 | - void *begin = &tss->SYSENTER_stack_canary; | |
| 75 | + void *begin = &tss->SYSENTER_stack; | |
| 76 | void *end = (void *)&tss->SYSENTER_stack + sizeof(tss->SYSENTER_stack); | |
| 77 | ||
| 78 | if ((void *)stack < begin || (void *)stack >= end) | |
| 79 | diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c | |
| 80 | index 407fc37a8718..ec758390d24e 100644 | |
| 81 | --- a/arch/x86/kernel/process.c | |
| 82 | +++ b/arch/x86/kernel/process.c | |
| 83 | @@ -80,7 +80,6 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = { | |
| 84 | */ | |
| 85 | .io_bitmap = { [0 ... IO_BITMAP_LONGS] = ~0 }, | |
| 86 | #endif | |
| 87 | - .SYSENTER_stack_canary = STACK_END_MAGIC, | |
| 88 | }; | |
| 89 | EXPORT_PER_CPU_SYMBOL(cpu_tss); | |
| 90 | ||
| 91 | diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c | |
| 92 | index fd4d47e8672e..2818c83892b3 100644 | |
| 93 | --- a/arch/x86/kernel/traps.c | |
| 94 | +++ b/arch/x86/kernel/traps.c | |
| 95 | @@ -826,13 +826,6 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code) | |
| 96 | debug_stack_usage_dec(); | |
| 97 | ||
| 98 | exit: | |
| 99 | - /* | |
| 100 | - * This is the most likely code path that involves non-trivial use | |
| 101 | - * of the SYSENTER stack. Check that we haven't overrun it. | |
| 102 | - */ | |
| 103 | - WARN(this_cpu_read(cpu_tss.SYSENTER_stack_canary) != STACK_END_MAGIC, | |
| 104 | - "Overran or corrupted SYSENTER stack\n"); | |
| 105 | - | |
| 106 | ist_exit(regs); | |
| 107 | } | |
| 108 | NOKPROBE_SYMBOL(do_debug); | |
| 109 | -- | |
| 110 | 2.14.2 | |
| 111 |