diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-19 13:22:42 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-19 13:22:42 -0800 |
| commit | a54455766b9e3d3c27a6cef758355d2591d81d68 (patch) | |
| tree | c7187cc528befc675d49950332a1d9fe0e3f638b /arch/x86 | |
| parent | 1092b596a56b6ac5fa3154dc75bfcbb6f27ac757 (diff) | |
| parent | 72e9b5fe9bee0826e7ce7599adbdc64e544780ef (diff) | |
Merge branch 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MPX fixes from Thomas Gleixner:
"Three updates for the new MPX infrastructure:
- Use the proper error check in the trap handler
- Add a proper config option for it
- Bring documentation up to date"
* 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, mpx: Give MPX a real config option prompt
x86, mpx: Update documentation
x86_64/traps: Fix always true condition
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/Kconfig | 30 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 2 |
2 files changed, 27 insertions, 5 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d69f1cd87fd9..2995788bcb1d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -249,10 +249,6 @@ config HAVE_INTEL_TXT def_bool y depends on INTEL_IOMMU && ACPI -config X86_INTEL_MPX - def_bool y - depends on CPU_SUP_INTEL - config X86_32_SMP def_bool y depends on X86_32 && SMP @@ -1594,6 +1590,32 @@ config X86_SMAP If unsure, say Y. +config X86_INTEL_MPX + prompt "Intel MPX (Memory Protection Extensions)" + def_bool n + depends on CPU_SUP_INTEL + ---help--- + MPX provides hardware features that can be used in + conjunction with compiler-instrumented code to check + memory references. It is designed to detect buffer + overflow or underflow bugs. + + This option enables running applications which are + instrumented or otherwise use MPX. It does not use MPX + itself inside the kernel or to protect the kernel + against bad memory references. + + Enabling this option will make the kernel larger: + ~8k of kernel text and 36 bytes of data on a 64-bit + defconfig. It adds a long to the 'mm_struct' which + will increase the kernel memory overhead of each + process and adds some branches to paths used during + exec() and munmap(). + + For details, see Documentation/x86/intel_mpx.txt + + If unsure, say N. + config EFI bool "EFI runtime service support" depends on ACPI diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index a9ae20579895..88900e288021 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -331,7 +331,7 @@ dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) break; /* Success, it was handled */ case 1: /* Bound violation. */ info = mpx_generate_siginfo(regs, xsave_buf); - if (PTR_ERR(info)) { + if (IS_ERR(info)) { /* * We failed to decode the MPX instruction. Act as if * the exception was not caused by MPX. |