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alistair23-linux/tools/testing/selftests/x86/protection_keys.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 08:07:57 -06:00
// SPDX-License-Identifier: GPL-2.0
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/*
* Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
*
* There are examples in here of:
* * how to set protection keys on memory
* * how to set/clear bits in PKRU (the rights register)
* * how to handle SEGV_PKRU signals and extract pkey-relevant
* information from the siginfo
*
* Things to add:
* make sure KSM and KSM COW breaking works
* prefault pages in at malloc, or not
* protect MPX bounds tables with protection keys?
* make sure VMA splitting/merging is working correctly
* OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
* look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
* do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
*
* Compile like this:
* gcc -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
* gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
*/
#define _GNU_SOURCE
#include <errno.h>
#include <linux/futex.h>
#include <sys/time.h>
#include <sys/syscall.h>
#include <string.h>
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <signal.h>
#include <assert.h>
#include <stdlib.h>
#include <ucontext.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ptrace.h>
#include <setjmp.h>
#include "pkey-helpers.h"
int iteration_nr = 1;
int test_nr;
unsigned int shadow_pkru;
#define HPAGE_SIZE (1UL<<21)
#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
#define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
#define ALIGN_PTR_DOWN(p, ptr_align_to) ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
#define __stringify_1(x...) #x
#define __stringify(x...) __stringify_1(x)
#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
int dprint_in_signal;
char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
extern void abort_hooks(void);
#define pkey_assert(condition) do { \
if (!(condition)) { \
dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
__FILE__, __LINE__, \
test_nr, iteration_nr); \
dprintf0("errno at assert: %d", errno); \
abort_hooks(); \
exit(__LINE__); \
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} \
} while (0)
void cat_into_file(char *str, char *file)
{
int fd = open(file, O_RDWR);
int ret;
dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
/*
* these need to be raw because they are called under
* pkey_assert()
*/
if (fd < 0) {
fprintf(stderr, "error opening '%s'\n", str);
perror("error: ");
exit(__LINE__);
}
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ret = write(fd, str, strlen(str));
if (ret != strlen(str)) {
perror("write to file failed");
fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
exit(__LINE__);
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}
close(fd);
}
#if CONTROL_TRACING > 0
static int warned_tracing;
int tracing_root_ok(void)
{
if (geteuid() != 0) {
if (!warned_tracing)
fprintf(stderr, "WARNING: not run as root, "
"can not do tracing control\n");
warned_tracing = 1;
return 0;
}
return 1;
}
#endif
void tracing_on(void)
{
#if CONTROL_TRACING > 0
#define TRACEDIR "/sys/kernel/debug/tracing"
char pidstr[32];
if (!tracing_root_ok())
return;
sprintf(pidstr, "%d", getpid());
cat_into_file("0", TRACEDIR "/tracing_on");
cat_into_file("\n", TRACEDIR "/trace");
if (1) {
cat_into_file("function_graph", TRACEDIR "/current_tracer");
cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
} else {
cat_into_file("nop", TRACEDIR "/current_tracer");
}
cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
cat_into_file("1", TRACEDIR "/tracing_on");
dprintf1("enabled tracing\n");
#endif
}
void tracing_off(void)
{
#if CONTROL_TRACING > 0
if (!tracing_root_ok())
return;
cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
#endif
}
void abort_hooks(void)
{
fprintf(stderr, "running %s()...\n", __func__);
tracing_off();
#ifdef SLEEP_ON_ABORT
sleep(SLEEP_ON_ABORT);
#endif
}
static inline void __page_o_noops(void)
{
/* 8-bytes of instruction * 512 bytes = 1 page */
asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
}
/*
* This attempts to have roughly a page of instructions followed by a few
* instructions that do a write, and another page of instructions. That
* way, we are pretty sure that the write is in the second page of
* instructions and has at least a page of padding behind it.
*
* *That* lets us be sure to madvise() away the write instruction, which
* will then fault, which makes sure that the fault code handles
* execute-only memory properly.
*/
__attribute__((__aligned__(PAGE_SIZE)))
void lots_o_noops_around_write(int *write_to_me)
{
dprintf3("running %s()\n", __func__);
__page_o_noops();
/* Assume this happens in the second page of instructions: */
*write_to_me = __LINE__;
/* pad out by another page: */
__page_o_noops();
dprintf3("%s() done\n", __func__);
}
/* Define some kernel-like types */
#define u8 uint8_t
#define u16 uint16_t
#define u32 uint32_t
#define u64 uint64_t
#ifdef __i386__
#ifndef SYS_mprotect_key
# define SYS_mprotect_key 380
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc 381
# define SYS_pkey_free 382
#endif
#define REG_IP_IDX REG_EIP
#define si_pkey_offset 0x14
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#else
#ifndef SYS_mprotect_key
# define SYS_mprotect_key 329
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc 330
# define SYS_pkey_free 331
#endif
#define REG_IP_IDX REG_RIP
#define si_pkey_offset 0x20
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#endif
void dump_mem(void *dumpme, int len_bytes)
{
char *c = (void *)dumpme;
int i;
for (i = 0; i < len_bytes; i += sizeof(u64)) {
u64 *ptr = (u64 *)(c + i);
dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
}
}
/* Failed address bound checks: */
#ifndef SEGV_BNDERR
# define SEGV_BNDERR 3
#endif
#ifndef SEGV_PKUERR
# define SEGV_PKUERR 4
#endif
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static char *si_code_str(int si_code)
{
if (si_code == SEGV_MAPERR)
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return "SEGV_MAPERR";
if (si_code == SEGV_ACCERR)
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return "SEGV_ACCERR";
if (si_code == SEGV_BNDERR)
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return "SEGV_BNDERR";
if (si_code == SEGV_PKUERR)
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return "SEGV_PKUERR";
return "UNKNOWN";
}
int pkru_faults;
int last_si_pkey = -1;
void signal_handler(int signum, siginfo_t *si, void *vucontext)
{
ucontext_t *uctxt = vucontext;
int trapno;
unsigned long ip;
char *fpregs;
u32 *pkru_ptr;
u64 siginfo_pkey;
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u32 *si_pkey_ptr;
int pkru_offset;
fpregset_t fpregset;
dprint_in_signal = 1;
dprintf1(">>>>===============SIGSEGV============================\n");
dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
__rdpkru(), shadow_pkru);
trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
fpregset = uctxt->uc_mcontext.fpregs;
fpregs = (void *)fpregset;
dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
trapno, ip, si_code_str(si->si_code), si->si_code);
#ifdef __i386__
/*
* 32-bit has some extra padding so that userspace can tell whether
* the XSTATE header is present in addition to the "legacy" FPU
* state. We just assume that it is here.
*/
fpregs += 0x70;
#endif
pkru_offset = pkru_xstate_offset();
pkru_ptr = (void *)(&fpregs[pkru_offset]);
dprintf1("siginfo: %p\n", si);
dprintf1(" fpregs: %p\n", fpregs);
/*
* If we got a PKRU fault, we *HAVE* to have at least one bit set in
* here.
*/
dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
if (DEBUG_LEVEL > 4)
dump_mem(pkru_ptr - 128, 256);
pkey_assert(*pkru_ptr);
if ((si->si_code == SEGV_MAPERR) ||
(si->si_code == SEGV_ACCERR) ||
(si->si_code == SEGV_BNDERR)) {
printf("non-PK si_code, exiting...\n");
exit(4);
}
si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
dump_mem((u8 *)si_pkey_ptr - 8, 24);
siginfo_pkey = *si_pkey_ptr;
pkey_assert(siginfo_pkey < NR_PKEYS);
last_si_pkey = siginfo_pkey;
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dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
/* need __rdpkru() version so we do not do shadow_pkru checking */
dprintf1("signal pkru from pkru: %08x\n", __rdpkru());
dprintf1("pkey from siginfo: %jx\n", siginfo_pkey);
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*(u64 *)pkru_ptr = 0x00000000;
dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
pkru_faults++;
dprintf1("<<<<==================================================\n");
dprint_in_signal = 0;
}
int wait_all_children(void)
{
int status;
return waitpid(-1, &status, 0);
}
void sig_chld(int x)
{
dprint_in_signal = 1;
dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
dprint_in_signal = 0;
}
void setup_sigsegv_handler(void)
{
int r, rs;
struct sigaction newact;
struct sigaction oldact;
/* #PF is mapped to sigsegv */
int signum = SIGSEGV;
newact.sa_handler = 0;
newact.sa_sigaction = signal_handler;
/*sigset_t - signals to block while in the handler */
/* get the old signal mask. */
rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
pkey_assert(rs == 0);
/* call sa_sigaction, not sa_handler*/
newact.sa_flags = SA_SIGINFO;
newact.sa_restorer = 0; /* void(*)(), obsolete */
r = sigaction(signum, &newact, &oldact);
r = sigaction(SIGALRM, &newact, &oldact);
pkey_assert(r == 0);
}
void setup_handlers(void)
{
signal(SIGCHLD, &sig_chld);
setup_sigsegv_handler();
}
pid_t fork_lazy_child(void)
{
pid_t forkret;
forkret = fork();
pkey_assert(forkret >= 0);
dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
if (!forkret) {
/* in the child */
while (1) {
dprintf1("child sleeping...\n");
sleep(30);
}
}
return forkret;
}
#ifndef PKEY_DISABLE_ACCESS
# define PKEY_DISABLE_ACCESS 0x1
#endif
#ifndef PKEY_DISABLE_WRITE
# define PKEY_DISABLE_WRITE 0x2
#endif
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static u32 hw_pkey_get(int pkey, unsigned long flags)
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{
u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
u32 pkru = __rdpkru();
u32 shifted_pkru;
u32 masked_pkru;
dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
__func__, pkey, flags, 0, 0);
dprintf2("%s() raw pkru: %x\n", __func__, pkru);
shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
masked_pkru = shifted_pkru & mask;
dprintf2("%s() masked pkru: %x\n", __func__, masked_pkru);
/*
* shift down the relevant bits to the lowest two, then
* mask off all the other high bits.
*/
return masked_pkru;
}
static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags)
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{
u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
u32 old_pkru = __rdpkru();
u32 new_pkru;
/* make sure that 'rights' only contains the bits we expect: */
assert(!(rights & ~mask));
/* copy old pkru */
new_pkru = old_pkru;
/* mask out bits from pkey in old value: */
new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
/* OR in new bits for pkey: */
new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
__wrpkru(new_pkru);
dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
__func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
return 0;
}
void pkey_disable_set(int pkey, int flags)
{
unsigned long syscall_flags = 0;
int ret;
int pkey_rights;
u32 orig_pkru = rdpkru();
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dprintf1("START->%s(%d, 0x%x)\n", __func__,
pkey, flags);
pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
pkey_rights = hw_pkey_get(pkey, syscall_flags);
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dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
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pkey, pkey, pkey_rights);
pkey_assert(pkey_rights >= 0);
pkey_rights |= flags;
ret = hw_pkey_set(pkey, pkey_rights, syscall_flags);
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assert(!ret);
/*pkru and flags have the same format */
shadow_pkru |= flags << (pkey * 2);
dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
pkey_assert(ret >= 0);
pkey_rights = hw_pkey_get(pkey, syscall_flags);
dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
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pkey, pkey, pkey_rights);
dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
if (flags)
pkey_assert(rdpkru() > orig_pkru);
dprintf1("END<---%s(%d, 0x%x)\n", __func__,
pkey, flags);
}
void pkey_disable_clear(int pkey, int flags)
{
unsigned long syscall_flags = 0;
int ret;
int pkey_rights = hw_pkey_get(pkey, syscall_flags);
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u32 orig_pkru = rdpkru();
pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
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pkey, pkey, pkey_rights);
pkey_assert(pkey_rights >= 0);
pkey_rights |= flags;
ret = hw_pkey_set(pkey, pkey_rights, 0);
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/* pkru and flags have the same format */
shadow_pkru &= ~(flags << (pkey * 2));
pkey_assert(ret >= 0);
pkey_rights = hw_pkey_get(pkey, syscall_flags);
dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
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pkey, pkey, pkey_rights);
dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
if (flags)
assert(rdpkru() > orig_pkru);
}
void pkey_write_allow(int pkey)
{
pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
}
void pkey_write_deny(int pkey)
{
pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
}
void pkey_access_allow(int pkey)
{
pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
}
void pkey_access_deny(int pkey)
{
pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
}
int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
unsigned long pkey)
{
int sret;
dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
ptr, size, orig_prot, pkey);
errno = 0;
sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
if (errno) {
dprintf2("SYS_mprotect_key sret: %d\n", sret);
dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
if (DEBUG_LEVEL >= 2)
perror("SYS_mprotect_pkey");
}
return sret;
}
int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
{
int ret = syscall(SYS_pkey_alloc, flags, init_val);
dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
__func__, flags, init_val, ret, errno);
return ret;
}
int alloc_pkey(void)
{
int ret;
unsigned long init_val = 0x0;
dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
__LINE__, __rdpkru(), shadow_pkru);
ret = sys_pkey_alloc(0, init_val);
/*
* pkey_alloc() sets PKRU, so we need to reflect it in
* shadow_pkru:
*/
dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
__LINE__, ret, __rdpkru(), shadow_pkru);
if (ret) {
/* clear both the bits: */
shadow_pkru &= ~(0x3 << (ret * 2));
dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
__LINE__, ret, __rdpkru(), shadow_pkru);
/*
* move the new state in from init_val
* (remember, we cheated and init_val == pkru format)
*/
shadow_pkru |= (init_val << (ret * 2));
}
dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
__LINE__, ret, __rdpkru(), shadow_pkru);
dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
/* for shadow checking: */
rdpkru();
dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
__LINE__, ret, __rdpkru(), shadow_pkru);
return ret;
}
int sys_pkey_free(unsigned long pkey)
{
int ret = syscall(SYS_pkey_free, pkey);
dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
return ret;
}
/*
* I had a bug where pkey bits could be set by mprotect() but
* not cleared. This ensures we get lots of random bit sets
* and clears on the vma and pte pkey bits.
*/
int alloc_random_pkey(void)
{
int max_nr_pkey_allocs;
int ret;
int i;
int alloced_pkeys[NR_PKEYS];
int nr_alloced = 0;
int random_index;
memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
/* allocate every possible key and make a note of which ones we got */
max_nr_pkey_allocs = NR_PKEYS;
max_nr_pkey_allocs = 1;
for (i = 0; i < max_nr_pkey_allocs; i++) {
int new_pkey = alloc_pkey();
if (new_pkey < 0)
break;
alloced_pkeys[nr_alloced++] = new_pkey;
}
pkey_assert(nr_alloced > 0);
/* select a random one out of the allocated ones */
random_index = rand() % nr_alloced;
ret = alloced_pkeys[random_index];
/* now zero it out so we don't free it next */
alloced_pkeys[random_index] = 0;
/* go through the allocated ones that we did not want and free them */
for (i = 0; i < nr_alloced; i++) {
int free_ret;
if (!alloced_pkeys[i])
continue;
free_ret = sys_pkey_free(alloced_pkeys[i]);
pkey_assert(!free_ret);
}
dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
__LINE__, ret, __rdpkru(), shadow_pkru);
return ret;
}
int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
unsigned long pkey)
{
int nr_iterations = random() % 100;
int ret;
while (0) {
int rpkey = alloc_random_pkey();
ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
ptr, size, orig_prot, pkey, ret);
if (nr_iterations-- < 0)
break;
dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
__LINE__, ret, __rdpkru(), shadow_pkru);
sys_pkey_free(rpkey);
dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
__LINE__, ret, __rdpkru(), shadow_pkru);
}
pkey_assert(pkey < NR_PKEYS);
ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
ptr, size, orig_prot, pkey, ret);
pkey_assert(!ret);
dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
__LINE__, ret, __rdpkru(), shadow_pkru);
return ret;
}
struct pkey_malloc_record {
void *ptr;
long size;
int prot;
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};
struct pkey_malloc_record *pkey_malloc_records;
struct pkey_malloc_record *pkey_last_malloc_record;
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long nr_pkey_malloc_records;
void record_pkey_malloc(void *ptr, long size, int prot)
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{
long i;
struct pkey_malloc_record *rec = NULL;
for (i = 0; i < nr_pkey_malloc_records; i++) {
rec = &pkey_malloc_records[i];
/* find a free record */
if (rec)
break;
}
if (!rec) {
/* every record is full */
size_t old_nr_records = nr_pkey_malloc_records;
size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
dprintf2("new_nr_records: %zd\n", new_nr_records);
dprintf2("new_size: %zd\n", new_size);
pkey_malloc_records = realloc(pkey_malloc_records, new_size);
pkey_assert(pkey_malloc_records != NULL);
rec = &pkey_malloc_records[nr_pkey_malloc_records];
/*
* realloc() does not initialize memory, so zero it from
* the first new record all the way to the end.
*/
for (i = 0; i < new_nr_records - old_nr_records; i++)
memset(rec + i, 0, sizeof(*rec));
}
dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
(int)(rec - pkey_malloc_records), rec, ptr, size);
rec->ptr = ptr;
rec->size = size;
rec->prot = prot;
pkey_last_malloc_record = rec;
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nr_pkey_malloc_records++;
}
void free_pkey_malloc(void *ptr)
{
long i;
int ret;
dprintf3("%s(%p)\n", __func__, ptr);
for (i = 0; i < nr_pkey_malloc_records; i++) {
struct pkey_malloc_record *rec = &pkey_malloc_records[i];
dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
ptr, i, rec, rec->ptr, rec->size);
if ((ptr < rec->ptr) ||
(ptr >= rec->ptr + rec->size))
continue;
dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
ptr, i, rec, rec->ptr, rec->size);
nr_pkey_malloc_records--;
ret = munmap(rec->ptr, rec->size);
dprintf3("munmap ret: %d\n", ret);
pkey_assert(!ret);
dprintf3("clearing rec->ptr, rec: %p\n", rec);
rec->ptr = NULL;
dprintf3("done clearing rec->ptr, rec: %p\n", rec);
return;
}
pkey_assert(false);
}
void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
{
void *ptr;
int ret;
rdpkru();
dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
size, prot, pkey);
pkey_assert(pkey < NR_PKEYS);
ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
pkey_assert(ptr != (void *)-1);
ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
pkey_assert(!ret);
record_pkey_malloc(ptr, size, prot);
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rdpkru();
dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
return ptr;
}
void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
{
int ret;
void *ptr;
dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
size, prot, pkey);
/*
* Guarantee we can fit at least one huge page in the resulting
* allocation by allocating space for 2:
*/
size = ALIGN_UP(size, HPAGE_SIZE * 2);
ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
pkey_assert(ptr != (void *)-1);
record_pkey_malloc(ptr, size, prot);
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mprotect_pkey(ptr, size, prot, pkey);
dprintf1("unaligned ptr: %p\n", ptr);
ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
dprintf1(" aligned ptr: %p\n", ptr);
ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
dprintf1("MADV_WILLNEED ret: %d\n", ret);
memset(ptr, 0, HPAGE_SIZE);
dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
return ptr;
}
int hugetlb_setup_ok;
#define GET_NR_HUGE_PAGES 10
void setup_hugetlbfs(void)
{
int err;
int fd;
char buf[] = "123";
if (geteuid() != 0) {
fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
return;
}
cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
/*
* Now go make sure that we got the pages and that they
* are 2M pages. Someone might have made 1G the default.
*/
fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
if (fd < 0) {
perror("opening sysfs 2M hugetlb config");
return;
}
/* -1 to guarantee leaving the trailing \0 */
err = read(fd, buf, sizeof(buf)-1);
close(fd);
if (err <= 0) {
perror("reading sysfs 2M hugetlb config");
return;
}
if (atoi(buf) != GET_NR_HUGE_PAGES) {
fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
buf, GET_NR_HUGE_PAGES);
return;
}
hugetlb_setup_ok = 1;
}
void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
{
void *ptr;
int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
if (!hugetlb_setup_ok)
return PTR_ERR_ENOTSUP;
dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
size = ALIGN_UP(size, HPAGE_SIZE * 2);
pkey_assert(pkey < NR_PKEYS);
ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
pkey_assert(ptr != (void *)-1);
mprotect_pkey(ptr, size, prot, pkey);
record_pkey_malloc(ptr, size, prot);
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dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
return ptr;
}
void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
{
void *ptr;
int fd;
dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
size, prot, pkey);
pkey_assert(pkey < NR_PKEYS);
fd = open("/dax/foo", O_RDWR);
pkey_assert(fd >= 0);
ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
pkey_assert(ptr != (void *)-1);
mprotect_pkey(ptr, size, prot, pkey);
record_pkey_malloc(ptr, size, prot);
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dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
close(fd);
return ptr;
}
void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
malloc_pkey_with_mprotect,
malloc_pkey_anon_huge,
malloc_pkey_hugetlb
/* can not do direct with the pkey_mprotect() API:
malloc_pkey_mmap_direct,
malloc_pkey_mmap_dax,
*/
};
void *malloc_pkey(long size, int prot, u16 pkey)
{
void *ret;
static int malloc_type;
int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
pkey_assert(pkey < NR_PKEYS);
while (1) {
pkey_assert(malloc_type < nr_malloc_types);
ret = pkey_malloc[malloc_type](size, prot, pkey);
pkey_assert(ret != (void *)-1);
malloc_type++;
if (malloc_type >= nr_malloc_types)
malloc_type = (random()%nr_malloc_types);
/* try again if the malloc_type we tried is unsupported */
if (ret == PTR_ERR_ENOTSUP)
continue;
break;
}
dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
size, prot, pkey, ret);
return ret;
}
int last_pkru_faults;
#define UNKNOWN_PKEY -2
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void expected_pk_fault(int pkey)
{
dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
__func__, last_pkru_faults, pkru_faults);
dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
pkey_assert(last_pkru_faults + 1 == pkru_faults);
/*
* For exec-only memory, we do not know the pkey in
* advance, so skip this check.
*/
if (pkey != UNKNOWN_PKEY)
pkey_assert(last_si_pkey == pkey);
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/*
* The signal handler shold have cleared out PKRU to let the
* test program continue. We now have to restore it.
*/
if (__rdpkru() != 0)
pkey_assert(0);
__wrpkru(shadow_pkru);
dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
__func__, shadow_pkru);
last_pkru_faults = pkru_faults;
last_si_pkey = -1;
}
#define do_not_expect_pk_fault(msg) do { \
if (last_pkru_faults != pkru_faults) \
dprintf0("unexpected PK fault: %s\n", msg); \
pkey_assert(last_pkru_faults == pkru_faults); \
} while (0)
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int test_fds[10] = { -1 };
int nr_test_fds;
void __save_test_fd(int fd)
{
pkey_assert(fd >= 0);
pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
test_fds[nr_test_fds] = fd;
nr_test_fds++;
}
int get_test_read_fd(void)
{
int test_fd = open("/etc/passwd", O_RDONLY);
__save_test_fd(test_fd);
return test_fd;
}
void close_test_fds(void)
{
int i;
for (i = 0; i < nr_test_fds; i++) {
if (test_fds[i] < 0)
continue;
close(test_fds[i]);
test_fds[i] = -1;
}
nr_test_fds = 0;
}
#define barrier() __asm__ __volatile__("": : :"memory")
__attribute__((noinline)) int read_ptr(int *ptr)
{
/*
* Keep GCC from optimizing this away somehow
*/
barrier();
return *ptr;
}
void test_read_of_write_disabled_region(int *ptr, u16 pkey)
{
int ptr_contents;
dprintf1("disabling write access to PKEY[1], doing read\n");
pkey_write_deny(pkey);
ptr_contents = read_ptr(ptr);
dprintf1("*ptr: %d\n", ptr_contents);
dprintf1("\n");
}
void test_read_of_access_disabled_region(int *ptr, u16 pkey)
{
int ptr_contents;
dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
rdpkru();
pkey_access_deny(pkey);
ptr_contents = read_ptr(ptr);
dprintf1("*ptr: %d\n", ptr_contents);
expected_pk_fault(pkey);
}
void test_write_of_write_disabled_region(int *ptr, u16 pkey)
{
dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
pkey_write_deny(pkey);
*ptr = __LINE__;
expected_pk_fault(pkey);
}
void test_write_of_access_disabled_region(int *ptr, u16 pkey)
{
dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
pkey_access_deny(pkey);
*ptr = __LINE__;
expected_pk_fault(pkey);
}
void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
{
int ret;
int test_fd = get_test_read_fd();
dprintf1("disabling access to PKEY[%02d], "
"having kernel read() to buffer\n", pkey);
pkey_access_deny(pkey);
ret = read(test_fd, ptr, 1);
dprintf1("read ret: %d\n", ret);
pkey_assert(ret);
}
void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
{
int ret;
int test_fd = get_test_read_fd();
pkey_write_deny(pkey);
ret = read(test_fd, ptr, 100);
dprintf1("read ret: %d\n", ret);
if (ret < 0 && (DEBUG_LEVEL > 0))
perror("verbose read result (OK for this to be bad)");
pkey_assert(ret);
}
void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
{
int pipe_ret, vmsplice_ret;
struct iovec iov;
int pipe_fds[2];
pipe_ret = pipe(pipe_fds);
pkey_assert(pipe_ret == 0);
dprintf1("disabling access to PKEY[%02d], "
"having kernel vmsplice from buffer\n", pkey);
pkey_access_deny(pkey);
iov.iov_base = ptr;
iov.iov_len = PAGE_SIZE;
vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
pkey_assert(vmsplice_ret == -1);
close(pipe_fds[0]);
close(pipe_fds[1]);
}
void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
{
int ignored = 0xdada;
int futex_ret;
int some_int = __LINE__;
dprintf1("disabling write to PKEY[%02d], "
"doing futex gunk in buffer\n", pkey);
*ptr = some_int;
pkey_write_deny(pkey);
futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
&ignored, ignored);
if (DEBUG_LEVEL > 0)
perror("futex");
dprintf1("futex() ret: %d\n", futex_ret);
}
/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
{
int err;
int i;
/* Note: 0 is the default pkey, so don't mess with it */
for (i = 1; i < NR_PKEYS; i++) {
if (pkey == i)
continue;
dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
err = sys_pkey_free(i);
pkey_assert(err);
err = sys_pkey_free(i);
pkey_assert(err);
err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
pkey_assert(err);
}
}
/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
{
int err;
int bad_pkey = NR_PKEYS+99;
/* pass a known-invalid pkey in: */
err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
pkey_assert(err);
}
void become_child(void)
{
pid_t forkret;
forkret = fork();
pkey_assert(forkret >= 0);
dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
if (!forkret) {
/* in the child */
return;
}
exit(0);
}
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/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
{
int err;
int allocated_pkeys[NR_PKEYS] = {0};
int nr_allocated_pkeys = 0;
int i;
for (i = 0; i < NR_PKEYS*3; i++) {
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int new_pkey;
dprintf1("%s() alloc loop: %d\n", __func__, i);
new_pkey = alloc_pkey();
dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
__LINE__, err, __rdpkru(), shadow_pkru);
rdpkru(); /* for shadow checking */
dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
if ((new_pkey == -1) && (errno == ENOSPC)) {
dprintf2("%s() failed to allocate pkey after %d tries\n",
__func__, nr_allocated_pkeys);
} else {
/*
* Ensure the number of successes never
* exceeds the number of keys supported
* in the hardware.
*/
pkey_assert(nr_allocated_pkeys < NR_PKEYS);
allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
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}
/*
* Make sure that allocation state is properly
* preserved across fork().
*/
if (i == NR_PKEYS*2)
become_child();
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}
dprintf3("%s()::%d\n", __func__, __LINE__);
/*
* There are 16 pkeys supported in hardware. Three are
* allocated by the time we get here:
* 1. The default key (0)
* 2. One possibly consumed by an execute-only mapping.
* 3. One allocated by the test code and passed in via
* 'pkey' to this function.
* Ensure that we can allocate at least another 13 (16-3).
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*/
pkey_assert(i >= NR_PKEYS-3);
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for (i = 0; i < nr_allocated_pkeys; i++) {
err = sys_pkey_free(allocated_pkeys[i]);
pkey_assert(!err);
rdpkru(); /* for shadow checking */
}
}
/*
* pkey 0 is special. It is allocated by default, so you do not
* have to call pkey_alloc() to use it first. Make sure that it
* is usable.
*/
void test_mprotect_with_pkey_0(int *ptr, u16 pkey)
{
long size;
int prot;
assert(pkey_last_malloc_record);
size = pkey_last_malloc_record->size;
/*
* This is a bit of a hack. But mprotect() requires
* huge-page-aligned sizes when operating on hugetlbfs.
* So, make sure that we use something that's a multiple
* of a huge page when we can.
*/
if (size >= HPAGE_SIZE)
size = HPAGE_SIZE;
prot = pkey_last_malloc_record->prot;
/* Use pkey 0 */
mprotect_pkey(ptr, size, prot, 0);
/* Make sure that we can set it back to the original pkey. */
mprotect_pkey(ptr, size, prot, pkey);
}
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void test_ptrace_of_child(int *ptr, u16 pkey)
{
__attribute__((__unused__)) int peek_result;
pid_t child_pid;
void *ignored = 0;
long ret;
int status;
/*
* This is the "control" for our little expermient. Make sure
* we can always access it when ptracing.
*/
int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
/*
* Fork a child which is an exact copy of this process, of course.
* That means we can do all of our tests via ptrace() and then plain
* memory access and ensure they work differently.
*/
child_pid = fork_lazy_child();
dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
if (ret)
perror("attach");
dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
pkey_assert(ret != -1);
ret = waitpid(child_pid, &status, WUNTRACED);
if ((ret != child_pid) || !(WIFSTOPPED(status))) {
fprintf(stderr, "weird waitpid result %ld stat %x\n",
ret, status);
pkey_assert(0);
}
dprintf2("waitpid ret: %ld\n", ret);
dprintf2("waitpid status: %d\n", status);
pkey_access_deny(pkey);
pkey_write_deny(pkey);
/* Write access, untested for now:
ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
pkey_assert(ret != -1);
dprintf1("poke at %p: %ld\n", peek_at, ret);
*/
/*
* Try to access the pkey-protected "ptr" via ptrace:
*/
ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
/* expect it to work, without an error: */
pkey_assert(ret != -1);
/* Now access from the current task, and expect an exception: */
peek_result = read_ptr(ptr);
expected_pk_fault(pkey);
/*
* Try to access the NON-pkey-protected "plain_ptr" via ptrace:
*/
ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
/* expect it to work, without an error: */
pkey_assert(ret != -1);
/* Now access from the current task, and expect NO exception: */
peek_result = read_ptr(plain_ptr);
do_not_expect_pk_fault("read plain pointer after ptrace");
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ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
pkey_assert(ret != -1);
ret = kill(child_pid, SIGKILL);
pkey_assert(ret != -1);
wait(&status);
free(plain_ptr_unaligned);
}
void *get_pointer_to_instructions(void)
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{
void *p1;
p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
/* lots_o_noops_around_write should be page-aligned already */
assert(p1 == &lots_o_noops_around_write);
/* Point 'p1' at the *second* page of the function: */
p1 += PAGE_SIZE;
/*
* Try to ensure we fault this in on next touch to ensure
* we get an instruction fault as opposed to a data one
*/
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madvise(p1, PAGE_SIZE, MADV_DONTNEED);
return p1;
}
void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
{
void *p1;
int scratch;
int ptr_contents;
int ret;
p1 = get_pointer_to_instructions();
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lots_o_noops_around_write(&scratch);
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
pkey_assert(!ret);
pkey_access_deny(pkey);
dprintf2("pkru: %x\n", rdpkru());
/*
* Make sure this is an *instruction* fault
*/
madvise(p1, PAGE_SIZE, MADV_DONTNEED);
lots_o_noops_around_write(&scratch);
do_not_expect_pk_fault("executing on PROT_EXEC memory");
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ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
expected_pk_fault(pkey);
}
void test_implicit_mprotect_exec_only_memory(int *ptr, u16 pkey)
{
void *p1;
int scratch;
int ptr_contents;
int ret;
dprintf1("%s() start\n", __func__);
p1 = get_pointer_to_instructions();
lots_o_noops_around_write(&scratch);
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
/* Use a *normal* mprotect(), not mprotect_pkey(): */
ret = mprotect(p1, PAGE_SIZE, PROT_EXEC);
pkey_assert(!ret);
dprintf2("pkru: %x\n", rdpkru());
/* Make sure this is an *instruction* fault */
madvise(p1, PAGE_SIZE, MADV_DONTNEED);
lots_o_noops_around_write(&scratch);
do_not_expect_pk_fault("executing on PROT_EXEC memory");
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
expected_pk_fault(UNKNOWN_PKEY);
/*
* Put the memory back to non-PROT_EXEC. Should clear the
* exec-only pkey off the VMA and allow it to be readable
* again. Go to PROT_NONE first to check for a kernel bug
* that did not clear the pkey when doing PROT_NONE.
*/
ret = mprotect(p1, PAGE_SIZE, PROT_NONE);
pkey_assert(!ret);
ret = mprotect(p1, PAGE_SIZE, PROT_READ|PROT_EXEC);
pkey_assert(!ret);
ptr_contents = read_ptr(p1);
do_not_expect_pk_fault("plain read on recently PROT_EXEC area");
}
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void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
{
int size = PAGE_SIZE;
int sret;
if (cpu_has_pku()) {
dprintf1("SKIP: %s: no CPU support\n", __func__);
return;
}
sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
pkey_assert(sret < 0);
}
void (*pkey_tests[])(int *ptr, u16 pkey) = {
test_read_of_write_disabled_region,
test_read_of_access_disabled_region,
test_write_of_write_disabled_region,
test_write_of_access_disabled_region,
test_kernel_write_of_access_disabled_region,
test_kernel_write_of_write_disabled_region,
test_kernel_gup_of_access_disabled_region,
test_kernel_gup_write_to_write_disabled_region,
test_executing_on_unreadable_memory,
test_implicit_mprotect_exec_only_memory,
test_mprotect_with_pkey_0,
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test_ptrace_of_child,
test_pkey_syscalls_on_non_allocated_pkey,
test_pkey_syscalls_bad_args,
test_pkey_alloc_exhaust,
};
void run_tests_once(void)
{
int *ptr;
int prot = PROT_READ|PROT_WRITE;
for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
int pkey;
int orig_pkru_faults = pkru_faults;
dprintf1("======================\n");
dprintf1("test %d preparing...\n", test_nr);
tracing_on();
pkey = alloc_random_pkey();
dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
dprintf1("test %d starting...\n", test_nr);
pkey_tests[test_nr](ptr, pkey);
dprintf1("freeing test memory: %p\n", ptr);
free_pkey_malloc(ptr);
sys_pkey_free(pkey);
dprintf1("pkru_faults: %d\n", pkru_faults);
dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
tracing_off();
close_test_fds();
printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
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dprintf1("======================\n\n");
}
iteration_nr++;
}
void pkey_setup_shadow(void)
{
shadow_pkru = __rdpkru();
}
int main(void)
{
int nr_iterations = 22;
setup_handlers();
printf("has pku: %d\n", cpu_has_pku());
if (!cpu_has_pku()) {
int size = PAGE_SIZE;
int *ptr;
printf("running PKEY tests for unsupported CPU/OS\n");
ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
assert(ptr != (void *)-1);
test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
exit(0);
}
pkey_setup_shadow();
printf("startup pkru: %x\n", rdpkru());
setup_hugetlbfs();
while (nr_iterations-- > 0)
run_tests_once();
printf("done (all tests OK)\n");
return 0;
}