[PATCH v2] ARM: kprobes: Add test cases for stack consuming instructions
From: Jon Medhurst (Tixy)
Date: Tue Dec 09 2014 - 11:43:40 EST
These have extra 'checker' functions associated with them so lets make
sure those get covered by testing. As they may create uninitialised
space on the stack we also update the test code to ensure such space is
consistent between test runs. This is done by disabling interrupts in
setup_test_context().
Signed-off-by: Jon Medhurst <tixy@xxxxxxxxxx>
---
OK, so I lied in [1] when I said I won't be looking at the test failure
for a few days, I had a sudden inspiration on how to fix things and the
changes to test-core.c in this patch are the result. Rest of the patch
is the same as the version posted in Wang Nan's v15 patch set [2]
With this change the kprobe test code passes on my TC2 with both ARM and
Thumb kernels and both with and without optprobes forced using
wait_for_kprobe_optimizer() hacks.
[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-December/309574.html
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-December/309399.html
arch/arm/probes/kprobes/test-arm.c | 17 +++++++++++++++--
arch/arm/probes/kprobes/test-core.c | 10 ++++++++++
arch/arm/probes/kprobes/test-thumb.c | 12 ++++++++++++
3 files changed, 37 insertions(+), 2 deletions(-)
diff --git a/arch/arm/probes/kprobes/test-arm.c b/arch/arm/probes/kprobes/test-arm.c
index fdeb300..9b3b1b4 100644
--- a/arch/arm/probes/kprobes/test-arm.c
+++ b/arch/arm/probes/kprobes/test-arm.c
@@ -12,6 +12,7 @@
#include <linux/module.h>
#include <asm/system_info.h>
#include <asm/opcodes.h>
+#include <asm/probes.h>
#include "test-core.h"
@@ -478,6 +479,7 @@ void kprobe_arm_test_cases(void)
TEST_RPR( "strh r",0, VAL1,", [r",1, 48,", -r",2, 24,"]")
TEST_RPR( "streqh r",14,VAL2,", [r",11,0, ", r",12, 48,"]")
TEST_UNSUPPORTED( "streqh r14, [r13, r12]")
+ TEST_UNSUPPORTED( "streqh r14, [r12, r13]")
TEST_RPR( "strh r",1, VAL1,", [r",2, 24,", r",3, 48,"]!")
TEST_RPR( "strneh r",12,VAL2,", [r",11,48,", -r",10,24,"]!")
TEST_RPR( "strh r",2, VAL1,", [r",3, 24,"], r",4, 48,"")
@@ -502,6 +504,9 @@ void kprobe_arm_test_cases(void)
TEST_RP( "strplh r",12,VAL2,", [r",11,24,", #-4]!")
TEST_RP( "strh r",2, VAL1,", [r",3, 24,"], #48")
TEST_RP( "strh r",10,VAL2,", [r",9, 64,"], #-48")
+ TEST_RP( "strh r",3, VAL1,", [r",13,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"]!")
+ TEST_UNSUPPORTED("strh r3, [r13, #-"__stringify(MAX_STACK_SIZE)"-8]!")
+ TEST_RP( "strh r",4, VAL1,", [r",14,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"-8]!")
TEST_UNSUPPORTED(__inst_arm(0xe1efc3b0) " @ strh r12, [pc, #48]!")
TEST_UNSUPPORTED(__inst_arm(0xe0c9f3b0) " @ strh pc, [r9], #48")
@@ -568,6 +573,7 @@ void kprobe_arm_test_cases(void)
TEST_RPR( "strd r",0, VAL1,", [r",1, 48,", -r",2,24,"]")
TEST_RPR( "strccd r",8, VAL2,", [r",11,0, ", r",12,48,"]")
TEST_UNSUPPORTED( "strccd r8, [r13, r12]")
+ TEST_UNSUPPORTED( "strccd r8, [r12, r13]")
TEST_RPR( "strd r",4, VAL1,", [r",2, 24,", r",3, 48,"]!")
TEST_RPR( "strcsd r",12,VAL2,", [r",11,48,", -r",10,24,"]!")
TEST_RPR( "strd r",2, VAL1,", [r",5, 24,"], r",4,48,"")
@@ -591,6 +597,9 @@ void kprobe_arm_test_cases(void)
TEST_RP( "strvcd r",12,VAL2,", [r",11,24,", #-16]!")
TEST_RP( "strd r",2, VAL1,", [r",4, 24,"], #48")
TEST_RP( "strd r",10,VAL2,", [r",9, 64,"], #-48")
+ TEST_RP( "strd r",6, VAL1,", [r",13,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"]!")
+ TEST_UNSUPPORTED("strd r6, [r13, #-"__stringify(MAX_STACK_SIZE)"-8]!")
+ TEST_RP( "strd r",4, VAL1,", [r",12,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"-8]!")
TEST_UNSUPPORTED(__inst_arm(0xe1efc3f0) " @ strd r12, [pc, #48]!")
TEST_P( "ldrd r0, [r",0, 24,", #-8]")
@@ -639,16 +648,20 @@ void kprobe_arm_test_cases(void)
TEST_RP( "str"byte" r",12,VAL2,", [r",11,24,", #-4]!") \
TEST_RP( "str"byte" r",2, VAL1,", [r",3, 24,"], #48") \
TEST_RP( "str"byte" r",10,VAL2,", [r",9, 64,"], #-48") \
+ TEST_RP( "str"byte" r",3, VAL1,", [r",13,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"]!") \
+ TEST_UNSUPPORTED("str"byte" r3, [r13, #-"__stringify(MAX_STACK_SIZE)"-8]!") \
+ TEST_RP( "str"byte" r",4, VAL1,", [r",10,TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"-8]!") \
TEST_RPR("str"byte" r",0, VAL1,", [r",1, 48,", -r",2, 24,"]") \
TEST_RPR("str"byte" r",14,VAL2,", [r",11,0, ", r",12, 48,"]") \
- TEST_UNSUPPORTED("str"byte" r14, [r13, r12]") \
+ TEST_UNSUPPORTED("str"byte" r14, [r13, r12]") \
+ TEST_UNSUPPORTED("str"byte" r14, [r12, r13]") \
TEST_RPR("str"byte" r",1, VAL1,", [r",2, 24,", r",3, 48,"]!") \
TEST_RPR("str"byte" r",12,VAL2,", [r",11,48,", -r",10,24,"]!") \
TEST_RPR("str"byte" r",2, VAL1,", [r",3, 24,"], r",4, 48,"") \
TEST_RPR("str"byte" r",10,VAL2,", [r",9, 48,"], -r",11,24,"") \
TEST_RPR("str"byte" r",0, VAL1,", [r",1, 24,", r",2, 32,", asl #1]")\
TEST_RPR("str"byte" r",14,VAL2,", [r",11,0, ", r",12, 32,", lsr #2]")\
- TEST_UNSUPPORTED("str"byte" r14, [r13, r12, lsr #2]")\
+ TEST_UNSUPPORTED("str"byte" r14, [r13, r12, lsr #2]") \
TEST_RPR("str"byte" r",1, VAL1,", [r",2, 24,", r",3, 32,", asr #3]!")\
TEST_RPR("str"byte" r",12,VAL2,", [r",11,24,", r",10, 4,", ror #31]!")\
TEST_P( "ldr"byte" r0, [r",0, 24,", #-2]") \
diff --git a/arch/arm/probes/kprobes/test-core.c b/arch/arm/probes/kprobes/test-core.c
index 7ab633d..2b854ed 100644
--- a/arch/arm/probes/kprobes/test-core.c
+++ b/arch/arm/probes/kprobes/test-core.c
@@ -1196,6 +1196,13 @@ static void setup_test_context(struct pt_regs *regs)
regs->uregs[arg->reg] =
(unsigned long)current_stack + arg->val;
memory_needs_checking = true;
+ /*
+ * Test memory at an address below SP is in danger of
+ * being altered by an interrupt occurring and pushing
+ * data onto the stack. Disable interrupts to stop this.
+ */
+ if (arg->reg == 13)
+ regs->ARM_cpsr |= PSR_I_BIT;
break;
}
case ARG_TYPE_MEM: {
@@ -1206,6 +1213,7 @@ static void setup_test_context(struct pt_regs *regs)
default:
break;
}
+
}
struct test_probe {
@@ -1272,6 +1280,8 @@ test_after_pre_handler(struct kprobe *p, struct pt_regs *regs)
/* Undo any changes done to SP by the test case */
regs->ARM_sp = (unsigned long)current_stack;
+ /* Enable interrupts in case setup_test_context diabled them */
+ regs->ARM_cpsr &= ~PSR_I_BIT;
container_of(p, struct test_probe, kprobe)->hit = test_instance;
return 0;
diff --git a/arch/arm/probes/kprobes/test-thumb.c b/arch/arm/probes/kprobes/test-thumb.c
index 6c6e9a9..e8cf193 100644
--- a/arch/arm/probes/kprobes/test-thumb.c
+++ b/arch/arm/probes/kprobes/test-thumb.c
@@ -11,6 +11,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/opcodes.h>
+#include <asm/probes.h>
#include "test-core.h"
@@ -416,6 +417,9 @@ void kprobe_thumb32_test_cases(void)
TEST_RR( "strd r",14,VAL2,", r",12,VAL1,", [sp, #16]!")
TEST_RRP("strd r",1, VAL1,", r",0, VAL2,", [r",7, 24,"], #16")
TEST_RR( "strd r",7, VAL2,", r",8, VAL1,", [sp], #-16")
+ TEST_RRP("strd r",6, VAL1,", r",7, VAL2,", [r",13, TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"]!")
+ TEST_UNSUPPORTED("strd r6, r7, [r13, #-"__stringify(MAX_STACK_SIZE)"-8]!")
+ TEST_RRP("strd r",4, VAL1,", r",5, VAL2,", [r",14, TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"-8]!")
TEST_UNSUPPORTED(__inst_thumb32(0xe9efec04) " @ strd r14, r12, [pc, #16]!")
TEST_UNSUPPORTED(__inst_thumb32(0xe8efec04) " @ strd r14, r12, [pc], #16")
@@ -821,14 +825,22 @@ CONDITION_INSTRUCTIONS(22,
TEST_RP( "str"size" r",14,VAL2,", [r",1, 256, ", #-128]!") \
TEST_RPR("str"size".w r",0, VAL1,", [r",1, 0,", r",2, 4,"]") \
TEST_RPR("str"size" r",14,VAL2,", [r",10,0,", r",11,4,", lsl #1]") \
+ TEST_UNSUPPORTED("str"size" r0, [r13, r1]") \
TEST_R( "str"size".w r",7, VAL1,", [sp, #24]") \
TEST_RP( "str"size".w r",0, VAL2,", [r",0,0, "]") \
+ TEST_RP( "str"size" r",6, VAL1,", [r",13, TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"]!") \
+ TEST_UNSUPPORTED("str"size" r6, [r13, #-"__stringify(MAX_STACK_SIZE)"-8]!") \
+ TEST_RP( "str"size" r",4, VAL2,", [r",12, TEST_MEMORY_SIZE,", #-"__stringify(MAX_STACK_SIZE)"-8]!") \
TEST_UNSUPPORTED("str"size"t r0, [r1, #4]")
SINGLE_STORE("b")
SINGLE_STORE("h")
SINGLE_STORE("")
+ TEST_UNSUPPORTED(__inst_thumb32(0xf801000d) " @ strb r0, [r1, r13]")
+ TEST_UNSUPPORTED(__inst_thumb32(0xf821000d) " @ strh r0, [r1, r13]")
+ TEST_UNSUPPORTED(__inst_thumb32(0xf841000d) " @ str r0, [r1, r13]")
+
TEST("str sp, [sp]")
TEST_UNSUPPORTED(__inst_thumb32(0xf8cfe000) " @ str r14, [pc]")
TEST_UNSUPPORTED(__inst_thumb32(0xf8cef000) " @ str pc, [r14]")
--
2.1.3
--
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