diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-24 09:47:32 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-24 09:47:32 -0700 |
commit | d88f48e12821ab4b2244124d50ac094568f48db5 (patch) | |
tree | 4eb16b46898190aac33ed6125a9a0e734d5be10e /tools/testing/selftests | |
parent | be53f58fa0fcd97c62a84f2eb98cff528f8b2443 (diff) | |
parent | 9da77666d6975219281fd400eb9608a047337414 (diff) |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- fix hotplug bugs
- fix irq live lock
- fix various topology handling bugs
- fix APIC ACK ordering
- fix PV iopl handling
- fix speling
- fix/tweak memcpy_mcsafe() return value
- fix fbcon bug
- remove stray prototypes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/msr: Remove unused native_read_tscp()
x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck
x86/oprofile/nmi: Add missing hotplug FROZEN handling
x86/hpet: Use proper mask to modify hotplug action
x86/apic/uv: Fix the hotplug notifier
x86/apb/timer: Use proper mask to modify hotplug action
x86/topology: Use total_cpus not nr_cpu_ids for logical packages
x86/topology: Fix Intel HT disable
x86/topology: Fix logical package mapping
x86/irq: Cure live lock in fixup_irqs()
x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known()
x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()
x86/iopl: Fix iopl capability check on Xen PV
x86/iopl/64: Properly context-switch IOPL on Xen PV
selftests/x86: Add an iopl test
x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe()
x86/video: Don't assume all FB devices are PCI devices
arch/x86/irq: Purge useless handler declarations from hw_irq.h
x86: Fix misspellings in comments
Diffstat (limited to 'tools/testing/selftests')
-rw-r--r-- | tools/testing/selftests/x86/Makefile | 2 | ||||
-rw-r--r-- | tools/testing/selftests/x86/iopl.c | 135 |
2 files changed, 136 insertions, 1 deletions
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index d5ce7d7aae3e..b47ebd170690 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -5,7 +5,7 @@ include ../lib.mk .PHONY: all all_32 all_64 warn_32bit_failure clean TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall \ - check_initial_reg_state sigreturn ldt_gdt + check_initial_reg_state sigreturn ldt_gdt iopl TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer diff --git a/tools/testing/selftests/x86/iopl.c b/tools/testing/selftests/x86/iopl.c new file mode 100644 index 000000000000..c496ca97bc18 --- /dev/null +++ b/tools/testing/selftests/x86/iopl.c @@ -0,0 +1,135 @@ +/* + * iopl.c - Test case for a Linux on Xen 64-bit bug + * Copyright (c) 2015 Andrew Lutomirski + */ + +#define _GNU_SOURCE +#include <err.h> +#include <stdio.h> +#include <stdint.h> +#include <signal.h> +#include <setjmp.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <stdbool.h> +#include <sched.h> +#include <sys/io.h> + +static int nerrs = 0; + +static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), + int flags) +{ + struct sigaction sa; + memset(&sa, 0, sizeof(sa)); + sa.sa_sigaction = handler; + sa.sa_flags = SA_SIGINFO | flags; + sigemptyset(&sa.sa_mask); + if (sigaction(sig, &sa, 0)) + err(1, "sigaction"); + +} + +static jmp_buf jmpbuf; + +static void sigsegv(int sig, siginfo_t *si, void *ctx_void) +{ + siglongjmp(jmpbuf, 1); +} + +int main(void) +{ + cpu_set_t cpuset; + CPU_ZERO(&cpuset); + CPU_SET(0, &cpuset); + if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0) + err(1, "sched_setaffinity to CPU 0"); + + /* Probe for iopl support. Note that iopl(0) works even as nonroot. */ + if (iopl(3) != 0) { + printf("[OK]\tiopl(3) failed (%d) -- try running as root\n", + errno); + return 0; + } + + /* Restore our original state prior to starting the test. */ + if (iopl(0) != 0) + err(1, "iopl(0)"); + + pid_t child = fork(); + if (child == -1) + err(1, "fork"); + + if (child == 0) { + printf("\tchild: set IOPL to 3\n"); + if (iopl(3) != 0) + err(1, "iopl"); + + printf("[RUN]\tchild: write to 0x80\n"); + asm volatile ("outb %%al, $0x80" : : "a" (0)); + + return 0; + } else { + int status; + if (waitpid(child, &status, 0) != child || + !WIFEXITED(status)) { + printf("[FAIL]\tChild died\n"); + nerrs++; + } else if (WEXITSTATUS(status) != 0) { + printf("[FAIL]\tChild failed\n"); + nerrs++; + } else { + printf("[OK]\tChild succeeded\n"); + } + } + + printf("[RUN]\tparent: write to 0x80 (should fail)\n"); + + sethandler(SIGSEGV, sigsegv, 0); + if (sigsetjmp(jmpbuf, 1) != 0) { + printf("[OK]\twrite was denied\n"); + } else { + asm volatile ("outb %%al, $0x80" : : "a" (0)); + printf("[FAIL]\twrite was allowed\n"); + nerrs++; + } + + /* Test the capability checks. */ + printf("\tiopl(3)\n"); + if (iopl(3) != 0) + err(1, "iopl(3)"); + + printf("\tDrop privileges\n"); + if (setresuid(1, 1, 1) != 0) { + printf("[WARN]\tDropping privileges failed\n"); + goto done; + } + + printf("[RUN]\tiopl(3) unprivileged but with IOPL==3\n"); + if (iopl(3) != 0) { + printf("[FAIL]\tiopl(3) should work if iopl is already 3 even if unprivileged\n"); + nerrs++; + } + + printf("[RUN]\tiopl(0) unprivileged\n"); + if (iopl(0) != 0) { + printf("[FAIL]\tiopl(0) should work if iopl is already 3 even if unprivileged\n"); + nerrs++; + } + + printf("[RUN]\tiopl(3) unprivileged\n"); + if (iopl(3) == 0) { + printf("[FAIL]\tiopl(3) should fail if when unprivileged if iopl==0\n"); + nerrs++; + } else { + printf("[OK]\tFailed as expected\n"); + } + +done: + return nerrs ? 1 : 0; +} + |