From: Sandipan Das <sandipan@linux.ibm.com>
To: mpe@ellerman.id.au
Cc: fweimer@redhat.com, aneesh.kumar@linux.ibm.com,
linuxram@us.ibm.com, linuxppc-dev@lists.ozlabs.org,
bauerman@linux.ibm.com
Subject: [PATCH 2/5] selftests/powerpc: Add pkey helpers for rights
Date: Thu, 16 Jul 2020 16:33:44 +0530 [thread overview]
Message-ID: <6cc1c7d1f686618668a3e090f1d0c2a4cd9dea3f.1594897099.git.sandipan@linux.ibm.com> (raw)
In-Reply-To: <cover.1594897099.git.sandipan@linux.ibm.com>
This adds some new pkey-related helper to print
access rights of a pkey in the "rwx" format and
to generate different valid combinations of pkey
rights starting from a given combination.
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
---
.../testing/selftests/powerpc/include/pkeys.h | 28 +++++++++++++++
.../selftests/powerpc/mm/pkey_exec_prot.c | 36 ++++++++++---------
2 files changed, 48 insertions(+), 16 deletions(-)
diff --git a/tools/testing/selftests/powerpc/include/pkeys.h b/tools/testing/selftests/powerpc/include/pkeys.h
index 9b53a97e664ea..6ba95039a0343 100644
--- a/tools/testing/selftests/powerpc/include/pkeys.h
+++ b/tools/testing/selftests/powerpc/include/pkeys.h
@@ -105,4 +105,32 @@ int siginfo_pkey(siginfo_t *si)
#endif
}
+#define pkey_rights(r) ({ \
+ static char buf[4] = "rwx"; \
+ unsigned int amr_bits; \
+ if ((r) & PKEY_DISABLE_EXECUTE) \
+ buf[2] = '-'; \
+ amr_bits = (r) & PKEY_BITS_MASK; \
+ if (amr_bits & PKEY_DISABLE_WRITE) \
+ buf[1] = '-'; \
+ if (amr_bits & PKEY_DISABLE_ACCESS & ~PKEY_DISABLE_WRITE) \
+ buf[0] = '-'; \
+ buf; \
+})
+
+unsigned long next_pkey_rights(unsigned long rights)
+{
+ if (rights == PKEY_DISABLE_ACCESS)
+ return PKEY_DISABLE_EXECUTE;
+ else if (rights == (PKEY_DISABLE_ACCESS | PKEY_DISABLE_EXECUTE))
+ return 0;
+
+ if ((rights & PKEY_BITS_MASK) == 0)
+ rights |= PKEY_DISABLE_WRITE;
+ else if ((rights & PKEY_BITS_MASK) == PKEY_DISABLE_WRITE)
+ rights |= PKEY_DISABLE_ACCESS;
+
+ return rights;
+}
+
#endif /* _SELFTESTS_POWERPC_PKEYS_H */
diff --git a/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c b/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c
index 1253ad6afba24..18ebfe6bae1c9 100644
--- a/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c
+++ b/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c
@@ -102,6 +102,7 @@ static void segv_handler(int signum, siginfo_t *sinfo, void *ctx)
static int test(void)
{
struct sigaction segv_act, trap_act;
+ unsigned long rights;
int pkey, ret, i;
ret = pkeys_unsupported();
@@ -150,7 +151,8 @@ static int test(void)
insns[numinsns - 1] = PPC_INST_BLR;
/* Allocate a pkey that restricts execution */
- pkey = sys_pkey_alloc(0, PKEY_DISABLE_EXECUTE);
+ rights = PKEY_DISABLE_EXECUTE;
+ pkey = sys_pkey_alloc(0, rights);
FAIL_IF(pkey < 0);
/*
@@ -175,8 +177,8 @@ static int test(void)
*/
remaining_faults = 0;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
- printf("read from %p, pkey is execute-disabled, access-enabled\n",
- (void *) fault_addr);
+ printf("read from %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
i = *fault_addr;
FAIL_IF(remaining_faults != 0);
@@ -192,12 +194,13 @@ static int test(void)
*/
remaining_faults = 1;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
- printf("write to %p, pkey is execute-disabled, access-enabled\n",
- (void *) fault_addr);
+ printf("write to %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
*fault_addr = PPC_INST_TRAP;
FAIL_IF(remaining_faults != 0 || fault_code != SEGV_ACCERR);
/* The following three cases will generate SEGV_PKUERR */
+ rights |= PKEY_DISABLE_ACCESS;
fault_type = PKEY_DISABLE_ACCESS;
fault_pkey = pkey;
@@ -211,9 +214,9 @@ static int test(void)
*/
remaining_faults = 1;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
- printf("read from %p, pkey is execute-disabled, access-disabled\n",
- (void *) fault_addr);
- pkey_set_rights(pkey, PKEY_DISABLE_ACCESS);
+ pkey_set_rights(pkey, rights);
+ printf("read from %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
i = *fault_addr;
FAIL_IF(remaining_faults != 0 || fault_code != SEGV_PKUERR);
@@ -228,9 +231,9 @@ static int test(void)
*/
remaining_faults = 2;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
- printf("write to %p, pkey is execute-disabled, access-disabled\n",
- (void *) fault_addr);
- pkey_set_rights(pkey, PKEY_DISABLE_ACCESS);
+ pkey_set_rights(pkey, rights);
+ printf("write to %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
*fault_addr = PPC_INST_NOP;
FAIL_IF(remaining_faults != 0 || fault_code != SEGV_ACCERR);
@@ -251,8 +254,8 @@ static int test(void)
remaining_faults = 1;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
pkey_set_rights(pkey, PKEY_DISABLE_ACCESS);
- printf("execute at %p, pkey is execute-disabled, access-disabled\n",
- (void *) fault_addr);
+ printf("execute at %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
asm volatile("mtctr %0; bctrl" : : "r"(insns));
FAIL_IF(remaining_faults != 0 || fault_code != SEGV_PKUERR);
@@ -261,7 +264,8 @@ static int test(void)
* fully permissive.
*/
sys_pkey_free(pkey);
- pkey = sys_pkey_alloc(0, 0);
+ rights = 0;
+ pkey = sys_pkey_alloc(0, rights);
/*
* Jump to the executable region when AMR bits are not set
@@ -274,8 +278,8 @@ static int test(void)
fault_pkey = pkey;
remaining_faults = 0;
FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0);
- printf("execute at %p, pkey is execute-enabled, access-enabled\n",
- (void *) fault_addr);
+ printf("execute at %p, pkey permissions are %s\n", fault_addr,
+ pkey_rights(rights));
asm volatile("mtctr %0; bctrl" : : "r"(insns));
FAIL_IF(remaining_faults != 0);
--
2.25.1
next prev parent reply other threads:[~2020-07-16 11:09 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-16 11:03 [PATCH 0/5] Improvements to pkey tests Sandipan Das
2020-07-16 11:03 ` [PATCH 1/5] selftests/powerpc: Move pkey helpers to headers Sandipan Das
2020-07-16 11:03 ` Sandipan Das [this message]
2020-07-16 11:03 ` [PATCH 3/5] selftests/powerpc: Harden test for execute-disabled pkeys Sandipan Das
2020-07-16 11:03 ` [PATCH 4/5] selftests/powerpc: Add helper to exit on failure Sandipan Das
2020-07-16 11:03 ` [PATCH 5/5] selftests/powerpc: Add test for pkey siginfo verification Sandipan Das
2020-07-26 14:05 ` Michael Ellerman
2020-07-26 14:40 ` Christophe Leroy
2020-07-26 23:52 ` Michael Ellerman
2020-07-27 3:27 ` Sandipan Das
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