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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-16 19:06:29 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-16 19:06:29 -0700 |
commit | e0d60a1e68a3fbf42cdf3546004e00230d9048ba (patch) | |
tree | e283f864ee0d53fa8df68701b463365e6b73683b /tools/testing | |
parent | 22331f895298bd23ca9f99f6a237aae883c9e1c7 (diff) | |
parent | 6365b842aae4490ebfafadfc6bb27a6d3cc54757 (diff) | |
download | linux-e0d60a1e68a3fbf42cdf3546004e00230d9048ba.tar.bz2 |
Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry updates from Ingo Molnar:
"This contains x32 and compat syscall improvements, the biggest one of
which splits x32 syscalls into their own table, which allows new
syscalls to share the x32 and x86-64 number - which turns the
512-547 special syscall numbers range into a legacy wart that won't be
extended going forward"
* 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/syscalls: Split the x32 syscalls into their own table
x86/syscalls: Disallow compat entries for all types of 64-bit syscalls
x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask()
x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long
Diffstat (limited to 'tools/testing')
-rw-r--r-- | tools/testing/selftests/x86/Makefile | 2 | ||||
-rw-r--r-- | tools/testing/selftests/x86/syscall_numbering.c | 89 |
2 files changed, 90 insertions, 1 deletions
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index 3bc5b744e644..5d49bfec1e9a 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -17,7 +17,7 @@ TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer -TARGETS_C_64BIT_ONLY := fsgsbase sysret_rip +TARGETS_C_64BIT_ONLY := fsgsbase sysret_rip syscall_numbering # Some selftests require 32bit support enabled also on 64bit systems TARGETS_C_32BIT_NEEDED := ldt_gdt ptrace_syscall diff --git a/tools/testing/selftests/x86/syscall_numbering.c b/tools/testing/selftests/x86/syscall_numbering.c new file mode 100644 index 000000000000..d6b09cb1aa2c --- /dev/null +++ b/tools/testing/selftests/x86/syscall_numbering.c @@ -0,0 +1,89 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * syscall_arg_fault.c - tests faults 32-bit fast syscall stack args + * Copyright (c) 2018 Andrew Lutomirski + */ + +#define _GNU_SOURCE + +#include <stdlib.h> +#include <stdio.h> +#include <stdbool.h> +#include <errno.h> +#include <unistd.h> +#include <syscall.h> + +static int nerrs; + +#define X32_BIT 0x40000000UL + +static void check_enosys(unsigned long nr, bool *ok) +{ + /* If this fails, a segfault is reasonably likely. */ + fflush(stdout); + + long ret = syscall(nr, 0, 0, 0, 0, 0, 0); + if (ret == 0) { + printf("[FAIL]\tsyscall %lu succeeded, but it should have failed\n", nr); + *ok = false; + } else if (errno != ENOSYS) { + printf("[FAIL]\tsyscall %lu had error code %d, but it should have reported ENOSYS\n", nr, errno); + *ok = false; + } +} + +static void test_x32_without_x32_bit(void) +{ + bool ok = true; + + /* + * Syscalls 512-547 are "x32" syscalls. They are intended to be + * called with the x32 (0x40000000) bit set. Calling them without + * the x32 bit set is nonsense and should not work. + */ + printf("[RUN]\tChecking syscalls 512-547\n"); + for (int i = 512; i <= 547; i++) + check_enosys(i, &ok); + + /* + * Check that a handful of 64-bit-only syscalls are rejected if the x32 + * bit is set. + */ + printf("[RUN]\tChecking some 64-bit syscalls in x32 range\n"); + check_enosys(16 | X32_BIT, &ok); /* ioctl */ + check_enosys(19 | X32_BIT, &ok); /* readv */ + check_enosys(20 | X32_BIT, &ok); /* writev */ + + /* + * Check some syscalls with high bits set. + */ + printf("[RUN]\tChecking numbers above 2^32-1\n"); + check_enosys((1UL << 32), &ok); + check_enosys(X32_BIT | (1UL << 32), &ok); + + if (!ok) + nerrs++; + else + printf("[OK]\tThey all returned -ENOSYS\n"); +} + +int main() +{ + /* + * Anyone diagnosing a failure will want to know whether the kernel + * supports x32. Tell them. + */ + printf("\tChecking for x32..."); + fflush(stdout); + if (syscall(39 | X32_BIT, 0, 0, 0, 0, 0, 0) >= 0) { + printf(" supported\n"); + } else if (errno == ENOSYS) { + printf(" not supported\n"); + } else { + printf(" confused\n"); + } + + test_x32_without_x32_bit(); + + return nerrs ? 1 : 0; +} |