[v2] selftests/lkdtm: Add tests for LKDTM targets
diff mbox series

Message ID 201912301453.19D686EE6@keescook
State New
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Series
  • [v2] selftests/lkdtm: Add tests for LKDTM targets
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Commit Message

Kees Cook Dec. 30, 2019, 10:57 p.m. UTC
This adds a basic framework for running all the "safe" LKDTM tests. This
will allow easy introspection into any selftest logs to examine the
results of most LKDTM tests.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
v2: refreshed for v5.5, added new tests since v1
v1: https://lore.kernel.org/lkml/201905091013.E228F0F0BE@keescook/
---
 MAINTAINERS                             |  1 +
 tools/testing/selftests/Makefile        |  1 +
 tools/testing/selftests/lkdtm/Makefile  | 12 ++++
 tools/testing/selftests/lkdtm/config    |  1 +
 tools/testing/selftests/lkdtm/run.sh    | 91 +++++++++++++++++++++++++
 tools/testing/selftests/lkdtm/tests.txt | 70 +++++++++++++++++++
 6 files changed, 176 insertions(+)
 create mode 100644 tools/testing/selftests/lkdtm/Makefile
 create mode 100644 tools/testing/selftests/lkdtm/config
 create mode 100755 tools/testing/selftests/lkdtm/run.sh
 create mode 100644 tools/testing/selftests/lkdtm/tests.txt

Comments

shuah Jan. 9, 2020, 11:19 p.m. UTC | #1
On 12/30/19 3:57 PM, Kees Cook wrote:
> This adds a basic framework for running all the "safe" LKDTM tests. This
> will allow easy introspection into any selftest logs to examine the
> results of most LKDTM tests.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
> v2: refreshed for v5.5, added new tests since v1
> v1: https://lore.kernel.org/lkml/201905091013.E228F0F0BE@keescook/
> ---
>   MAINTAINERS                             |  1 +
>   tools/testing/selftests/Makefile        |  1 +
>   tools/testing/selftests/lkdtm/Makefile  | 12 ++++
>   tools/testing/selftests/lkdtm/config    |  1 +
>   tools/testing/selftests/lkdtm/run.sh    | 91 +++++++++++++++++++++++++
>   tools/testing/selftests/lkdtm/tests.txt | 70 +++++++++++++++++++
>   6 files changed, 176 insertions(+)
>   create mode 100644 tools/testing/selftests/lkdtm/Makefile
>   create mode 100644 tools/testing/selftests/lkdtm/config
>   create mode 100755 tools/testing/selftests/lkdtm/run.sh
>   create mode 100644 tools/testing/selftests/lkdtm/tests.txt
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cc0a4a8ae06a..eacc00c6cfd5 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9578,6 +9578,7 @@ LINUX KERNEL DUMP TEST MODULE (LKDTM)
>   M:	Kees Cook <keescook@chromium.org>
>   S:	Maintained
>   F:	drivers/misc/lkdtm/*
> +F:	tools/testing/selftests/lkdtm/*
>   
>   LINUX KERNEL MEMORY CONSISTENCY MODEL (LKMM)
>   M:	Alan Stern <stern@rowland.harvard.edu>
> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
> index b001c602414b..f0b02a12ba39 100644
> --- a/tools/testing/selftests/Makefile
> +++ b/tools/testing/selftests/Makefile
> @@ -26,6 +26,7 @@ TARGETS += kexec
>   TARGETS += kvm
>   TARGETS += lib
>   TARGETS += livepatch
> +TARGETS += lkdtm
>   TARGETS += membarrier
>   TARGETS += memfd
>   TARGETS += memory-hotplug
> diff --git a/tools/testing/selftests/lkdtm/Makefile b/tools/testing/selftests/lkdtm/Makefile
> new file mode 100644
> index 000000000000..1bcc9ee990eb
> --- /dev/null
> +++ b/tools/testing/selftests/lkdtm/Makefile
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0
> +# Makefile for LKDTM regression tests
> +
> +include ../lib.mk
> +
> +# NOTE: $(OUTPUT) won't get default value if used before lib.mk
> +TEST_FILES := tests.txt
> +TEST_GEN_PROGS = $(patsubst %,$(OUTPUT)/%.sh,$(shell awk '{print $$1}' tests.txt | sed -e 's/\#//'))
> +all: $(TEST_GEN_PROGS)
> +
> +$(OUTPUT)/%: run.sh tests.txt
> +	install -m 0744 run.sh $@
> diff --git a/tools/testing/selftests/lkdtm/config b/tools/testing/selftests/lkdtm/config
> new file mode 100644
> index 000000000000..d874990e442b
> --- /dev/null
> +++ b/tools/testing/selftests/lkdtm/config
> @@ -0,0 +1 @@
> +CONFIG_LKDTM=y
> diff --git a/tools/testing/selftests/lkdtm/run.sh b/tools/testing/selftests/lkdtm/run.sh
> new file mode 100755
> index 000000000000..793ee0d5d5a3
> --- /dev/null
> +++ b/tools/testing/selftests/lkdtm/run.sh
> @@ -0,0 +1,91 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# This reads tests.txt for the list of LKDTM tests to invoke. Any marked
> +# with a leading "#" are skipped. The rest of the line after the
> +# test name is either the text to look for in dmesg for a "success",
> +# or the rationale for why a test is marked to be skipped.
> +#
> +set -e
> +TRIGGER=/sys/kernel/debug/provoke-crash/DIRECT
> +
> +# Verify we have LKDTM available in the kernel.
> +if [ ! -r $TRIGGER ] ; then
> +	/sbin/modprobe -q lkdtm || true
> +	if [ ! -r $TRIGGER ] ; then
> +		echo "Cannot find $TRIGGER (missing CONFIG_LKDTM?)"
> +	else
> +		echo "Cannot write $TRIGGER (need to run as root?)"
> +	fi
> +	# Skip this test
> +	exit 4

Please add a define for this to indicate that this the kselftest
skip code.

> +fi
> +
> +# Figure out which test to run from our script name.
> +test=$(basename $0 .sh)
> +# Look up details about the test from master list of LKDTM tests.
> +line=$(egrep '^#?'"$test"'\b' tests.txt)
> +if [ -z "$line" ]; then
> +	echo "Skipped: missing test '$test' in tests.txt"
> +	exit 4
> +fi
> +# Check that the test is known to LKDTM.
> +if ! egrep -q '^'"$test"'$' "$TRIGGER" ; then
> +	echo "Skipped: test '$test' missing in $TRIGGER!"
> +	exit 4
> +fi

Same here

> +
> +# Extract notes/expected output from test list.
> +test=$(echo "$line" | cut -d" " -f1)
> +if echo "$line" | grep -q ' ' ; then
> +	expect=$(echo "$line" | cut -d" " -f2-)
> +else
> +	expect=""
> +fi
> +
> +# If the test is commented out, report a skip
> +if echo "$test" | grep -q '^#' ; then
> +	test=$(echo "$test" | cut -c2-)
> +	if [ -z "$expect" ]; then
> +		expect="crashes entire system"
> +	fi
> +	echo "Skipping $test: $expect"
> +	exit 4

Same here

> +fi
> +
> +# If no expected output given, assume an Oops with back trace is success.
> +if [ -z "$expect" ]; then
> +	expect="call trace:"
> +fi
> +
> +# Clear out dmesg for output reporting
> +dmesg -c >/dev/null
> +
> +# Prepare log for report checking
> +LOG=$(mktemp --tmpdir -t lkdtm-XXXXXX)
> +cleanup() {
> +	rm -f "$LOG"
> +}
> +trap cleanup EXIT
> +
> +# Most shells yell about signals and we're expecting the "cat" process
> +# to usually be killed by the kernel. So we have to run it in a sub-shell
> +# and silence errors.
> +($SHELL -c 'cat <(echo '"$test"') >'"$TRIGGER" 2>/dev/null) || true
> +
> +# Record and dump the results
> +dmesg -c >"$LOG"
> +cat "$LOG"
> +# Check for expected output
> +if egrep -qi "$expect" "$LOG" ; then
> +	echo "$test: saw '$expect': ok"
> +	exit 0
> +else
> +	if egrep -qi XFAIL: "$LOG" ; then
> +		echo "$test: saw 'XFAIL': [SKIP]"
> +		exit 4
> +	else
> +		echo "$test: missing '$expect': [FAIL]"
> +		exit 1
> +	fi
> +fi
> diff --git a/tools/testing/selftests/lkdtm/tests.txt b/tools/testing/selftests/lkdtm/tests.txt
> new file mode 100644
> index 000000000000..fc55f8ef8bee
> --- /dev/null
> +++ b/tools/testing/selftests/lkdtm/tests.txt
> @@ -0,0 +1,70 @@
> +#PANIC
> +BUG kernel BUG at
> +WARNING WARNING:
> +WARNING_MESSAGE message trigger
> +EXCEPTION
> +#LOOP Hangs the system
> +#EXHAUST_STACK Corrupts memory on failure
> +#CORRUPT_STACK Crashes entire system on success
> +#CORRUPT_STACK_STRONG Crashes entire system on success
> +CORRUPT_LIST_ADD list_add corruption
> +CORRUPT_LIST_DEL list_del corruption
> +CORRUPT_USER_DS Invalid address limit on user-mode return
> +STACK_GUARD_PAGE_LEADING
> +STACK_GUARD_PAGE_TRAILING
> +UNSET_SMEP CR4 bits went missing
> +UNALIGNED_LOAD_STORE_WRITE
> +#OVERWRITE_ALLOCATION Corrupts memory on failure
> +#WRITE_AFTER_FREE Corrupts memory on failure
> +READ_AFTER_FREE
> +#WRITE_BUDDY_AFTER_FREE Corrupts memory on failure
> +READ_BUDDY_AFTER_FREE
> +SLAB_FREE_DOUBLE
> +SLAB_FREE_CROSS
> +SLAB_FREE_PAGE
> +#SOFTLOCKUP Hangs the system
> +#HARDLOCKUP Hangs the system
> +#SPINLOCKUP Hangs the system
> +#HUNG_TASK Hangs the system
> +EXEC_DATA
> +EXEC_STACK
> +EXEC_KMALLOC
> +EXEC_VMALLOC
> +EXEC_RODATA
> +EXEC_USERSPACE
> +EXEC_NULL
> +ACCESS_USERSPACE
> +ACCESS_NULL
> +WRITE_RO
> +WRITE_RO_AFTER_INIT
> +WRITE_KERN
> +REFCOUNT_INC_OVERFLOW
> +REFCOUNT_ADD_OVERFLOW
> +REFCOUNT_INC_NOT_ZERO_OVERFLOW
> +REFCOUNT_ADD_NOT_ZERO_OVERFLOW
> +REFCOUNT_DEC_ZERO
> +REFCOUNT_DEC_NEGATIVE Negative detected: saturated
> +REFCOUNT_DEC_AND_TEST_NEGATIVE Negative detected: saturated
> +REFCOUNT_SUB_AND_TEST_NEGATIVE Negative detected: saturated
> +REFCOUNT_INC_ZERO
> +REFCOUNT_ADD_ZERO
> +REFCOUNT_INC_SATURATED Saturation detected: still saturated
> +REFCOUNT_DEC_SATURATED Saturation detected: still saturated
> +REFCOUNT_ADD_SATURATED Saturation detected: still saturated
> +REFCOUNT_INC_NOT_ZERO_SATURATED
> +REFCOUNT_ADD_NOT_ZERO_SATURATED
> +REFCOUNT_DEC_AND_TEST_SATURATED Saturation detected: still saturated
> +REFCOUNT_SUB_AND_TEST_SATURATED Saturation detected: still saturated
> +#REFCOUNT_TIMING timing only
> +#ATOMIC_TIMING timing only
> +USERCOPY_HEAP_SIZE_TO
> +USERCOPY_HEAP_SIZE_FROM
> +USERCOPY_HEAP_WHITELIST_TO
> +USERCOPY_HEAP_WHITELIST_FROM
> +USERCOPY_STACK_FRAME_TO
> +USERCOPY_STACK_FRAME_FROM
> +USERCOPY_STACK_BEYOND
> +USERCOPY_KERNEL
> +USERCOPY_KERNEL_DS
> +STACKLEAK_ERASING OK: the rest of the thread stack is properly erased
> +CFI_FORWARD_PROTO
> 

Rest looks good. I can pull the v3 for 5.6-rc1

thanks,
-- Shuah

Patch
diff mbox series

diff --git a/MAINTAINERS b/MAINTAINERS
index cc0a4a8ae06a..eacc00c6cfd5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9578,6 +9578,7 @@  LINUX KERNEL DUMP TEST MODULE (LKDTM)
 M:	Kees Cook <keescook@chromium.org>
 S:	Maintained
 F:	drivers/misc/lkdtm/*
+F:	tools/testing/selftests/lkdtm/*
 
 LINUX KERNEL MEMORY CONSISTENCY MODEL (LKMM)
 M:	Alan Stern <stern@rowland.harvard.edu>
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index b001c602414b..f0b02a12ba39 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -26,6 +26,7 @@  TARGETS += kexec
 TARGETS += kvm
 TARGETS += lib
 TARGETS += livepatch
+TARGETS += lkdtm
 TARGETS += membarrier
 TARGETS += memfd
 TARGETS += memory-hotplug
diff --git a/tools/testing/selftests/lkdtm/Makefile b/tools/testing/selftests/lkdtm/Makefile
new file mode 100644
index 000000000000..1bcc9ee990eb
--- /dev/null
+++ b/tools/testing/selftests/lkdtm/Makefile
@@ -0,0 +1,12 @@ 
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for LKDTM regression tests
+
+include ../lib.mk
+
+# NOTE: $(OUTPUT) won't get default value if used before lib.mk
+TEST_FILES := tests.txt
+TEST_GEN_PROGS = $(patsubst %,$(OUTPUT)/%.sh,$(shell awk '{print $$1}' tests.txt | sed -e 's/\#//'))
+all: $(TEST_GEN_PROGS)
+
+$(OUTPUT)/%: run.sh tests.txt
+	install -m 0744 run.sh $@
diff --git a/tools/testing/selftests/lkdtm/config b/tools/testing/selftests/lkdtm/config
new file mode 100644
index 000000000000..d874990e442b
--- /dev/null
+++ b/tools/testing/selftests/lkdtm/config
@@ -0,0 +1 @@ 
+CONFIG_LKDTM=y
diff --git a/tools/testing/selftests/lkdtm/run.sh b/tools/testing/selftests/lkdtm/run.sh
new file mode 100755
index 000000000000..793ee0d5d5a3
--- /dev/null
+++ b/tools/testing/selftests/lkdtm/run.sh
@@ -0,0 +1,91 @@ 
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# This reads tests.txt for the list of LKDTM tests to invoke. Any marked
+# with a leading "#" are skipped. The rest of the line after the
+# test name is either the text to look for in dmesg for a "success",
+# or the rationale for why a test is marked to be skipped.
+#
+set -e
+TRIGGER=/sys/kernel/debug/provoke-crash/DIRECT
+
+# Verify we have LKDTM available in the kernel.
+if [ ! -r $TRIGGER ] ; then
+	/sbin/modprobe -q lkdtm || true
+	if [ ! -r $TRIGGER ] ; then
+		echo "Cannot find $TRIGGER (missing CONFIG_LKDTM?)"
+	else
+		echo "Cannot write $TRIGGER (need to run as root?)"
+	fi
+	# Skip this test
+	exit 4
+fi
+
+# Figure out which test to run from our script name.
+test=$(basename $0 .sh)
+# Look up details about the test from master list of LKDTM tests.
+line=$(egrep '^#?'"$test"'\b' tests.txt)
+if [ -z "$line" ]; then
+	echo "Skipped: missing test '$test' in tests.txt"
+	exit 4
+fi
+# Check that the test is known to LKDTM.
+if ! egrep -q '^'"$test"'$' "$TRIGGER" ; then
+	echo "Skipped: test '$test' missing in $TRIGGER!"
+	exit 4
+fi
+
+# Extract notes/expected output from test list.
+test=$(echo "$line" | cut -d" " -f1)
+if echo "$line" | grep -q ' ' ; then
+	expect=$(echo "$line" | cut -d" " -f2-)
+else
+	expect=""
+fi
+
+# If the test is commented out, report a skip
+if echo "$test" | grep -q '^#' ; then
+	test=$(echo "$test" | cut -c2-)
+	if [ -z "$expect" ]; then
+		expect="crashes entire system"
+	fi
+	echo "Skipping $test: $expect"
+	exit 4
+fi
+
+# If no expected output given, assume an Oops with back trace is success.
+if [ -z "$expect" ]; then
+	expect="call trace:"
+fi
+
+# Clear out dmesg for output reporting
+dmesg -c >/dev/null
+
+# Prepare log for report checking
+LOG=$(mktemp --tmpdir -t lkdtm-XXXXXX)
+cleanup() {
+	rm -f "$LOG"
+}
+trap cleanup EXIT
+
+# Most shells yell about signals and we're expecting the "cat" process
+# to usually be killed by the kernel. So we have to run it in a sub-shell
+# and silence errors.
+($SHELL -c 'cat <(echo '"$test"') >'"$TRIGGER" 2>/dev/null) || true
+
+# Record and dump the results
+dmesg -c >"$LOG"
+cat "$LOG"
+# Check for expected output
+if egrep -qi "$expect" "$LOG" ; then
+	echo "$test: saw '$expect': ok"
+	exit 0
+else
+	if egrep -qi XFAIL: "$LOG" ; then
+		echo "$test: saw 'XFAIL': [SKIP]"
+		exit 4
+	else
+		echo "$test: missing '$expect': [FAIL]"
+		exit 1
+	fi
+fi
diff --git a/tools/testing/selftests/lkdtm/tests.txt b/tools/testing/selftests/lkdtm/tests.txt
new file mode 100644
index 000000000000..fc55f8ef8bee
--- /dev/null
+++ b/tools/testing/selftests/lkdtm/tests.txt
@@ -0,0 +1,70 @@ 
+#PANIC
+BUG kernel BUG at
+WARNING WARNING:
+WARNING_MESSAGE message trigger
+EXCEPTION
+#LOOP Hangs the system
+#EXHAUST_STACK Corrupts memory on failure
+#CORRUPT_STACK Crashes entire system on success
+#CORRUPT_STACK_STRONG Crashes entire system on success
+CORRUPT_LIST_ADD list_add corruption
+CORRUPT_LIST_DEL list_del corruption
+CORRUPT_USER_DS Invalid address limit on user-mode return
+STACK_GUARD_PAGE_LEADING
+STACK_GUARD_PAGE_TRAILING
+UNSET_SMEP CR4 bits went missing
+UNALIGNED_LOAD_STORE_WRITE
+#OVERWRITE_ALLOCATION Corrupts memory on failure
+#WRITE_AFTER_FREE Corrupts memory on failure
+READ_AFTER_FREE
+#WRITE_BUDDY_AFTER_FREE Corrupts memory on failure
+READ_BUDDY_AFTER_FREE
+SLAB_FREE_DOUBLE
+SLAB_FREE_CROSS
+SLAB_FREE_PAGE
+#SOFTLOCKUP Hangs the system
+#HARDLOCKUP Hangs the system
+#SPINLOCKUP Hangs the system
+#HUNG_TASK Hangs the system
+EXEC_DATA
+EXEC_STACK
+EXEC_KMALLOC
+EXEC_VMALLOC
+EXEC_RODATA
+EXEC_USERSPACE
+EXEC_NULL
+ACCESS_USERSPACE
+ACCESS_NULL
+WRITE_RO
+WRITE_RO_AFTER_INIT
+WRITE_KERN
+REFCOUNT_INC_OVERFLOW
+REFCOUNT_ADD_OVERFLOW
+REFCOUNT_INC_NOT_ZERO_OVERFLOW
+REFCOUNT_ADD_NOT_ZERO_OVERFLOW
+REFCOUNT_DEC_ZERO
+REFCOUNT_DEC_NEGATIVE Negative detected: saturated
+REFCOUNT_DEC_AND_TEST_NEGATIVE Negative detected: saturated
+REFCOUNT_SUB_AND_TEST_NEGATIVE Negative detected: saturated
+REFCOUNT_INC_ZERO
+REFCOUNT_ADD_ZERO
+REFCOUNT_INC_SATURATED Saturation detected: still saturated
+REFCOUNT_DEC_SATURATED Saturation detected: still saturated
+REFCOUNT_ADD_SATURATED Saturation detected: still saturated
+REFCOUNT_INC_NOT_ZERO_SATURATED
+REFCOUNT_ADD_NOT_ZERO_SATURATED
+REFCOUNT_DEC_AND_TEST_SATURATED Saturation detected: still saturated
+REFCOUNT_SUB_AND_TEST_SATURATED Saturation detected: still saturated
+#REFCOUNT_TIMING timing only
+#ATOMIC_TIMING timing only
+USERCOPY_HEAP_SIZE_TO
+USERCOPY_HEAP_SIZE_FROM
+USERCOPY_HEAP_WHITELIST_TO
+USERCOPY_HEAP_WHITELIST_FROM
+USERCOPY_STACK_FRAME_TO
+USERCOPY_STACK_FRAME_FROM
+USERCOPY_STACK_BEYOND
+USERCOPY_KERNEL
+USERCOPY_KERNEL_DS
+STACKLEAK_ERASING OK: the rest of the thread stack is properly erased
+CFI_FORWARD_PROTO