From: Ram Pai linuxram@us.ibm.com
This makes use of the abstractions added earlier and introduces support for powerpc.
cc: Dave Hansen dave.hansen@intel.com cc: Florian Weimer fweimer@redhat.com Signed-off-by: Ram Pai linuxram@us.ibm.com Signed-off-by: Sandipan Das sandipan@linux.ibm.com --- tools/testing/selftests/vm/pkey-helpers.h | 2 + tools/testing/selftests/vm/pkey-powerpc.h | 93 +++++++ tools/testing/selftests/vm/protection_keys.c | 269 ++++++++++--------- 3 files changed, 236 insertions(+), 128 deletions(-) create mode 100644 tools/testing/selftests/vm/pkey-powerpc.h
diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h index c929cc09b3cc..5de06d3a81de 100644 --- a/tools/testing/selftests/vm/pkey-helpers.h +++ b/tools/testing/selftests/vm/pkey-helpers.h @@ -79,6 +79,8 @@ void expected_pkey_fault(int pkey);
#if defined(__i386__) || defined(__x86_64__) /* arch */ #include "pkey-x86.h" +#elif defined(__powerpc64__) /* arch */ +#include "pkey-powerpc.h" #else /* arch */ #error Architecture not supported #endif /* arch */ diff --git a/tools/testing/selftests/vm/pkey-powerpc.h b/tools/testing/selftests/vm/pkey-powerpc.h new file mode 100644 index 000000000000..5ced9c58fa4a --- /dev/null +++ b/tools/testing/selftests/vm/pkey-powerpc.h @@ -0,0 +1,93 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _PKEYS_POWERPC_H +#define _PKEYS_POWERPC_H + +#ifndef SYS_mprotect_key +# define SYS_mprotect_key 386 +#endif +#ifndef SYS_pkey_alloc +# define SYS_pkey_alloc 384 +# define SYS_pkey_free 385 +#endif +#define REG_IP_IDX PT_NIP +#define REG_TRAPNO PT_TRAP +#define gregs gp_regs +#define fpregs fp_regs +#define si_pkey_offset 0x20 + +#ifndef PKEY_DISABLE_ACCESS +# define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */ +#endif + +#ifndef PKEY_DISABLE_WRITE +# define PKEY_DISABLE_WRITE 0x2 +#endif + +#define NR_PKEYS 32 +#define NR_RESERVED_PKEYS_4K 27 /* pkey-0, pkey-1, exec-only-pkey + and 24 other keys that cannot be + represented in the PTE */ +#define NR_RESERVED_PKEYS_64K 3 /* pkey-0, pkey-1 and exec-only-pkey */ +#define PKEY_BITS_PER_PKEY 2 +#define HPAGE_SIZE (1UL << 24) +#define PAGE_SIZE (1UL << 16) +#define pkey_reg_t u64 +#define PKEY_REG_FMT "%016lx" + +static inline u32 pkey_bit_position(int pkey) +{ + return (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY; +} + +static inline pkey_reg_t __read_pkey_reg(void) +{ + pkey_reg_t pkey_reg; + + asm volatile("mfspr %0, 0xd" : "=r" (pkey_reg)); + + return pkey_reg; +} + +static inline void __write_pkey_reg(pkey_reg_t pkey_reg) +{ + pkey_reg_t eax = pkey_reg; + + dprintf4("%s() changing "PKEY_REG_FMT" to "PKEY_REG_FMT"\n", + __func__, __read_pkey_reg(), pkey_reg); + + asm volatile("mtspr 0xd, %0" : : "r" ((unsigned long)(eax)) : "memory"); + + dprintf4("%s() pkey register after changing "PKEY_REG_FMT" to " + PKEY_REG_FMT"\n", __func__, __read_pkey_reg(), + pkey_reg); +} + +static inline int cpu_has_pku(void) +{ + return 1; +} + +static inline int get_arch_reserved_keys(void) +{ + if (sysconf(_SC_PAGESIZE) == 4096) + return NR_RESERVED_PKEYS_4K; + else + return NR_RESERVED_PKEYS_64K; +} + +void expect_fault_on_read_execonly_key(void *p1, int pkey) +{ + /* + * powerpc does not allow userspace to change permissions of exec-only + * keys since those keys are not allocated by userspace. The signal + * handler wont be able to reset the permissions, which means the code + * will infinitely continue to segfault here. + */ + return; +} + +/* 8-bytes of instruction * 16384bytes = 1 page */ +#define __page_o_noops() asm(".rept 16384 ; nop; .endr") + +#endif /* _PKEYS_POWERPC_H */ diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index dbc2918bec13..1920bca84def 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -168,6 +168,125 @@ void dump_mem(void *dumpme, int len_bytes) } }
+static u32 hw_pkey_get(int pkey, unsigned long flags) +{ + pkey_reg_t pkey_reg = __read_pkey_reg(); + + dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n", + __func__, pkey, flags, 0, 0); + dprintf2("%s() raw pkey_reg: "PKEY_REG_FMT"\n", __func__, pkey_reg); + + return (u32) get_pkey_bits(pkey_reg, pkey); +} + +static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags) +{ + u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE); + pkey_reg_t old_pkey_reg = __read_pkey_reg(); + pkey_reg_t new_pkey_reg; + + /* make sure that 'rights' only contains the bits we expect: */ + assert(!(rights & ~mask)); + + /* modify bits accordingly in old pkey_reg and assign it */ + new_pkey_reg = set_pkey_bits(old_pkey_reg, pkey, rights); + + __write_pkey_reg(new_pkey_reg); + + dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x" + " pkey_reg now: "PKEY_REG_FMT" old_pkey_reg: "PKEY_REG_FMT"\n", + __func__, pkey, rights, flags, 0, __read_pkey_reg(), + old_pkey_reg); + return 0; +} + +void pkey_disable_set(int pkey, int flags) +{ + unsigned long syscall_flags = 0; + int ret; + int pkey_rights; + pkey_reg_t orig_pkey_reg = read_pkey_reg(); + + 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); + + dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, + pkey, pkey, pkey_rights); + + pkey_assert(pkey_rights >= 0); + + pkey_rights |= flags; + + ret = hw_pkey_set(pkey, pkey_rights, syscall_flags); + assert(!ret); + /* pkey_reg and flags have the same format */ + shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights); + dprintf1("%s(%d) shadow: 0x"PKEY_REG_FMT"\n", + __func__, pkey, shadow_pkey_reg); + + pkey_assert(ret >= 0); + + pkey_rights = hw_pkey_get(pkey, syscall_flags); + dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, + pkey, pkey, pkey_rights); + + dprintf1("%s(%d) pkey_reg: 0x"PKEY_REG_FMT"\n", + __func__, pkey, read_pkey_reg()); + if (flags) + pkey_assert(read_pkey_reg() >= orig_pkey_reg); + 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); + pkey_reg_t orig_pkey_reg = read_pkey_reg(); + + pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); + + dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, + pkey, pkey, pkey_rights); + pkey_assert(pkey_rights >= 0); + + pkey_rights &= ~flags; + + ret = hw_pkey_set(pkey, pkey_rights, 0); + shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights); + pkey_assert(ret >= 0); + + pkey_rights = hw_pkey_get(pkey, syscall_flags); + dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, + pkey, pkey, pkey_rights); + + dprintf1("%s(%d) pkey_reg: 0x"PKEY_REG_FMT"\n", __func__, + pkey, read_pkey_reg()); + if (flags) + assert(read_pkey_reg() <= orig_pkey_reg); +} + +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); +} + /* Failed address bound checks: */ #ifndef SEGV_BNDERR # define SEGV_BNDERR 3 @@ -198,11 +317,12 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext) int trapno; unsigned long ip; char *fpregs; +#if defined(__i386__) || defined(__x86_64__) /* arch */ pkey_reg_t *pkey_reg_ptr; + int pkey_reg_offset; +#endif /* arch */ u64 siginfo_pkey; u32 *si_pkey_ptr; - int pkey_reg_offset; - fpregset_t fpregset;
dprint_in_signal = 1; dprintf1(">>>>===============SIGSEGV============================\n"); @@ -212,12 +332,13 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO]; ip = uctxt->uc_mcontext.gregs[REG_IP_IDX]; - fpregset = uctxt->uc_mcontext.fpregs; - fpregs = (void *)fpregset; + fpregs = (char *) uctxt->uc_mcontext.fpregs;
dprintf2("%s() trapno: %d ip: 0x%016lx info->si_code: %s/%d\n", __func__, trapno, ip, si_code_str(si->si_code), si->si_code); + +#if defined(__i386__) || defined(__x86_64__) /* arch */ #ifdef __i386__ /* * 32-bit has some extra padding so that userspace can tell whether @@ -225,12 +346,10 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext) * state. We just assume that it is here. */ fpregs += 0x70; -#endif +#endif /* i386 */ pkey_reg_offset = pkey_reg_xstate_offset(); pkey_reg_ptr = (void *)(&fpregs[pkey_reg_offset]);
- dprintf1("siginfo: %p\n", si); - dprintf1(" fpregs: %p\n", fpregs); /* * If we got a PKEY fault, we *HAVE* to have at least one bit set in * here. @@ -239,6 +358,10 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext) if (DEBUG_LEVEL > 4) dump_mem(pkey_reg_ptr - 128, 256); pkey_assert(*pkey_reg_ptr); +#endif /* arch */ + + dprintf1("siginfo: %p\n", si); + dprintf1(" fpregs: %p\n", fpregs);
if ((si->si_code == SEGV_MAPERR) || (si->si_code == SEGV_ACCERR) || @@ -247,14 +370,13 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext) exit(4); }
- si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset); + si_pkey_ptr = siginfo_get_pkey_ptr(si); 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;
- dprintf1("signal pkey_reg from xsave: "PKEY_REG_FMT"\n", *pkey_reg_ptr); /* * need __read_pkey_reg() version so we do not do shadow_pkey_reg * checking @@ -262,8 +384,14 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext) dprintf1("signal pkey_reg from pkey_reg: "PKEY_REG_FMT"\n", __read_pkey_reg()); dprintf1("pkey from siginfo: %jx\n", siginfo_pkey); +#if defined(__i386__) || defined(__x86_64__) /* arch */ + dprintf1("signal pkey_reg from xsave: "PKEY_REG_FMT"\n", *pkey_reg_ptr); *(u64 *)pkey_reg_ptr = 0x00000000; dprintf1("WARNING: set PKEY_REG=0 to allow faulting instruction to continue\n"); +#elif defined(__powerpc64__) /* arch */ + /* restore access and let the faulting instruction continue */ + pkey_access_allow(siginfo_pkey); +#endif /* arch */ pkey_faults++; dprintf1("<<<<==================================================\n"); dprint_in_signal = 0; @@ -332,125 +460,6 @@ pid_t fork_lazy_child(void) return forkret; }
-static u32 hw_pkey_get(int pkey, unsigned long flags) -{ - pkey_reg_t pkey_reg = __read_pkey_reg(); - - dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n", - __func__, pkey, flags, 0, 0); - dprintf2("%s() raw pkey_reg: "PKEY_REG_FMT"\n", __func__, pkey_reg); - - return (u32) get_pkey_bits(pkey_reg, pkey); -} - -static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags) -{ - u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE); - pkey_reg_t old_pkey_reg = __read_pkey_reg(); - pkey_reg_t new_pkey_reg; - - /* make sure that 'rights' only contains the bits we expect: */ - assert(!(rights & ~mask)); - - /* modify bits accordingly in old pkey_reg and assign it */ - new_pkey_reg = set_pkey_bits(old_pkey_reg, pkey, rights); - - __write_pkey_reg(new_pkey_reg); - - dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x" - " pkey_reg now: "PKEY_REG_FMT" old_pkey_reg: "PKEY_REG_FMT"\n", - __func__, pkey, rights, flags, 0, __read_pkey_reg(), - old_pkey_reg); - return 0; -} - -void pkey_disable_set(int pkey, int flags) -{ - unsigned long syscall_flags = 0; - int ret; - int pkey_rights; - pkey_reg_t orig_pkey_reg = read_pkey_reg(); - - 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); - - dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, - pkey, pkey, pkey_rights); - - pkey_assert(pkey_rights >= 0); - - pkey_rights |= flags; - - ret = hw_pkey_set(pkey, pkey_rights, syscall_flags); - assert(!ret); - /* pkey_reg and flags have the same format */ - shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights); - dprintf1("%s(%d) shadow: 0x"PKEY_REG_FMT"\n", - __func__, pkey, shadow_pkey_reg); - - pkey_assert(ret >= 0); - - pkey_rights = hw_pkey_get(pkey, syscall_flags); - dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, - pkey, pkey, pkey_rights); - - dprintf1("%s(%d) pkey_reg: 0x"PKEY_REG_FMT"\n", - __func__, pkey, read_pkey_reg()); - if (flags) - pkey_assert(read_pkey_reg() >= orig_pkey_reg); - 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); - pkey_reg_t orig_pkey_reg = read_pkey_reg(); - - pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); - - dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, - pkey, pkey, pkey_rights); - pkey_assert(pkey_rights >= 0); - - pkey_rights &= ~flags; - - ret = hw_pkey_set(pkey, pkey_rights, 0); - shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights); - pkey_assert(ret >= 0); - - pkey_rights = hw_pkey_get(pkey, syscall_flags); - dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, - pkey, pkey, pkey_rights); - - dprintf1("%s(%d) pkey_reg: 0x"PKEY_REG_FMT"\n", __func__, - pkey, read_pkey_reg()); - if (flags) - assert(read_pkey_reg() <= orig_pkey_reg); -} - -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) { @@ -889,11 +898,15 @@ void expected_pkey_fault(int pkey) if (pkey != UNKNOWN_PKEY) pkey_assert(last_si_pkey == pkey);
+#if defined(__i386__) || defined(__x86_64__) /* arch */ /* * The signal handler shold have cleared out PKEY register to let the * test program continue. We now have to restore it. */ if (__read_pkey_reg() != 0) +#else /* arch */ + if (__read_pkey_reg() != shadow_pkey_reg) +#endif /* arch */ pkey_assert(0);
__write_pkey_reg(shadow_pkey_reg);