Add a series of tests to validate the RV tracefs API and basic
functionality.
* available monitors:
Check that all monitors (from the monitors folder) appear as
available and have a description. Works with nested monitors.
* enable/disable:
Enable and disable all monitors and validate both the enabled file
and the enabled_monitors. Check that enabling container monitors
enables all nested monitors.
* reactors:
Set all reactors and validate the setting, also for nested monitors.
* wwnr with printk:
wwnr is broken on purpose, run it with a load and check that the
printk reactor works. Also validate disabling reacting_on or
monitoring_on prevents reactions.
These tests use the ftracetest suite. The first patch of the series
adapts ftracetest to make this possible.
The enable/disable test cannot pass on upstream without the application
of the fix in [1].
[1] - https://lore.kernel.org/lkml/87tt0t4u19.fsf@yellow.woof
To: Steven Rostedt <rostedt(a)goodmis.org>
To: Nam Cao <namcao(a)linutronix.de>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: John Kacur <jkacur(a)redhat.com>
Cc: Waylon Cude <wcude(a)redhat.com>
Cc: linux-trace-kernel(a)vger.kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Gabriele Monaco (2):
selftest/ftrace: Generalise ftracetest to use with RV
selftests/verification: Add initial RV tests
MAINTAINERS | 1 +
tools/testing/selftests/ftrace/ftracetest | 34 ++++++---
.../ftrace/test.d/00basic/mount_options.tc | 2 +-
.../testing/selftests/ftrace/test.d/functions | 6 +-
.../testing/selftests/verification/.gitignore | 2 +
tools/testing/selftests/verification/Makefile | 8 ++
tools/testing/selftests/verification/config | 1 +
tools/testing/selftests/verification/settings | 1 +
.../selftests/verification/test.d/functions | 39 ++++++++++
.../test.d/rv_monitor_enable_disable.tc | 75 +++++++++++++++++++
.../verification/test.d/rv_monitor_reactor.tc | 68 +++++++++++++++++
.../test.d/rv_monitors_available.tc | 18 +++++
.../verification/test.d/rv_wwnr_printk.tc | 29 +++++++
.../verification/verificationtest-ktap | 8 ++
14 files changed, 278 insertions(+), 14 deletions(-)
create mode 100644 tools/testing/selftests/verification/.gitignore
create mode 100644 tools/testing/selftests/verification/Makefile
create mode 100644 tools/testing/selftests/verification/config
create mode 100644 tools/testing/selftests/verification/settings
create mode 100644 tools/testing/selftests/verification/test.d/functions
create mode 100644 tools/testing/selftests/verification/test.d/rv_monitor_enable_disable.tc
create mode 100644 tools/testing/selftests/verification/test.d/rv_monitor_reactor.tc
create mode 100644 tools/testing/selftests/verification/test.d/rv_monitors_available.tc
create mode 100644 tools/testing/selftests/verification/test.d/rv_wwnr_printk.tc
create mode 100644 tools/testing/selftests/verification/verificationtest-ktap
base-commit: cec1e6e5d1ab33403b809f79cd20d6aff124ccfe
--
2.51.0
kunit_device_register() only returns error pointers, not NULL.
Furthermore for regular users who aren't testing the KUnit API
itself, errors most likely represent major system failure (e.g. OOM
or sysfs collision) beyond the scope of their own test conditions.
Replace the assert with straightforward error handling for clarity.
Signed-off-by: Robin Murphy <robin.murphy(a)arm.com>
---
This seemed the logical conclusion by inspection, but please do correct
me if I've misunderstood the intent...
---
Documentation/dev-tools/kunit/usage.rst | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst
index 038f480074fd..3452c739dd44 100644
--- a/Documentation/dev-tools/kunit/usage.rst
+++ b/Documentation/dev-tools/kunit/usage.rst
@@ -873,7 +873,8 @@ For example:
// Create a fake device.
fake_device = kunit_device_register(test, "my_device");
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_device)
+ if (IS_ERR(fake_device))
+ return;
// Pass it to functions which need a device.
dev_managed_string = devm_kstrdup(fake_device, "Hello, World!");
--
2.34.1
From: Li RongQing <lirongqing(a)baidu.com>
Currently, when 'hung_task_panic' is enabled, the kernel panics
immediately upon detecting the first hung task. However, some hung
tasks are transient and allow system recovery, while persistent hangs
should trigger a panic when accumulating beyond a threshold.
Extend the 'hung_task_panic' sysctl to accept a threshold value
specifying the number of hung tasks that must be detected before
triggering a kernel panic. This provides finer control for environments
where transient hangs may occur but persistent hangs should be fatal.
The sysctl now accepts:
- 0: don't panic (maintains original behavior)
- 1: panic on first hung task (maintains original behavior)
- N > 1: panic after N hung tasks are detected in a single scan
This maintains backward compatibility while providing flexibility for
different hang scenarios.
Signed-off-by: Li RongQing <lirongqing(a)baidu.com>
Cc: Andrew Jeffery <andrew(a)codeconstruct.com.au>
Cc: Anshuman Khandual <anshuman.khandual(a)arm.com>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Florian Wesphal <fw(a)strlen.de>
Cc: Jakub Kacinski <kuba(a)kernel.org>
Cc: Jason A. Donenfeld <jason(a)zx2c4.com>
Cc: Joel Granados <joel.granados(a)kernel.org>
Cc: Joel Stanley <joel(a)jms.id.au>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Kees Cook <kees(a)kernel.org>
Cc: Lance Yang <lance.yang(a)linux.dev>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: "Paul E . McKenney" <paulmck(a)kernel.org>
Cc: Pawan Gupta <pawan.kumar.gupta(a)linux.intel.com>
Cc: Petr Mladek <pmladek(a)suse.com>
Cc: Phil Auld <pauld(a)redhat.com>
Cc: Randy Dunlap <rdunlap(a)infradead.org>
Cc: Russell King <linux(a)armlinux.org.uk>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Simon Horman <horms(a)kernel.org>
Cc: Stanislav Fomichev <sdf(a)fomichev.me>
Cc: Steven Rostedt <rostedt(a)goodmis.org>
---
diff with v3: comments modification, suggested by Lance, Masami, Randy and Petr
diff with v2: do not add a new sysctl, extend hung_task_panic, suggested by Kees Cook
Documentation/admin-guide/kernel-parameters.txt | 20 +++++++++++++-------
Documentation/admin-guide/sysctl/kernel.rst | 9 +++++----
arch/arm/configs/aspeed_g5_defconfig | 2 +-
kernel/configs/debug.config | 2 +-
kernel/hung_task.c | 15 ++++++++++-----
lib/Kconfig.debug | 9 +++++----
tools/testing/selftests/wireguard/qemu/kernel.config | 2 +-
7 files changed, 36 insertions(+), 23 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a51ab46..492f0bc 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1992,14 +1992,20 @@
the added memory block itself do not be affected.
hung_task_panic=
- [KNL] Should the hung task detector generate panics.
- Format: 0 | 1
+ [KNL] Number of hung tasks to trigger kernel panic.
+ Format: <int>
+
+ When set to a non-zero value, a kernel panic will be triggered if
+ the number of detected hung tasks reaches this value.
+
+ 0: don't panic
+ 1: panic immediately on first hung task
+ N: panic after N hung tasks are detected in a single scan
- A value of 1 instructs the kernel to panic when a
- hung task is detected. The default value is controlled
- by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
- option. The value selected by this boot parameter can
- be changed later by the kernel.hung_task_panic sysctl.
+ The default value is controlled by the
+ CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time option. The value
+ selected by this boot parameter can be changed later by the
+ kernel.hung_task_panic sysctl.
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
terminal devices. Valid values: 0..8
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index f3ee807..0065a55 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -397,13 +397,14 @@ a hung task is detected.
hung_task_panic
===============
-Controls the kernel's behavior when a hung task is detected.
+When set to a non-zero value, a kernel panic will be triggered if the
+number of hung tasks found during a single scan reaches this value.
This file shows up if ``CONFIG_DETECT_HUNG_TASK`` is enabled.
-= =================================================
+= =======================================================
0 Continue operation. This is the default behavior.
-1 Panic immediately.
-= =================================================
+N Panic when N hung tasks are found during a single scan.
+= =======================================================
hung_task_check_count
diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig
index 61cee1e..c3b0d5f 100644
--- a/arch/arm/configs/aspeed_g5_defconfig
+++ b/arch/arm/configs/aspeed_g5_defconfig
@@ -308,7 +308,7 @@ CONFIG_PANIC_ON_OOPS=y
CONFIG_PANIC_TIMEOUT=-1
CONFIG_SOFTLOCKUP_DETECTOR=y
CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y
-CONFIG_BOOTPARAM_HUNG_TASK_PANIC=y
+CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1
CONFIG_WQ_WATCHDOG=y
# CONFIG_SCHED_DEBUG is not set
CONFIG_FUNCTION_TRACER=y
diff --git a/kernel/configs/debug.config b/kernel/configs/debug.config
index e81327d..9f6ab7d 100644
--- a/kernel/configs/debug.config
+++ b/kernel/configs/debug.config
@@ -83,7 +83,7 @@ CONFIG_SLUB_DEBUG_ON=y
#
# Debug Oops, Lockups and Hangs
#
-# CONFIG_BOOTPARAM_HUNG_TASK_PANIC is not set
+CONFIG_BOOTPARAM_HUNG_TASK_PANIC=0
# CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC is not set
CONFIG_DEBUG_ATOMIC_SLEEP=y
CONFIG_DETECT_HUNG_TASK=y
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index b2c1f14..84b4b04 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -81,7 +81,7 @@ static unsigned int __read_mostly sysctl_hung_task_all_cpu_backtrace;
* hung task is detected:
*/
static unsigned int __read_mostly sysctl_hung_task_panic =
- IS_ENABLED(CONFIG_BOOTPARAM_HUNG_TASK_PANIC);
+ CONFIG_BOOTPARAM_HUNG_TASK_PANIC;
static int
hung_task_panic(struct notifier_block *this, unsigned long event, void *ptr)
@@ -218,8 +218,11 @@ static inline void debug_show_blocker(struct task_struct *task, unsigned long ti
}
#endif
-static void check_hung_task(struct task_struct *t, unsigned long timeout)
+static void check_hung_task(struct task_struct *t, unsigned long timeout,
+ unsigned long prev_detect_count)
{
+ unsigned long total_hung_task;
+
if (!task_is_hung(t, timeout))
return;
@@ -229,9 +232,10 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
*/
sysctl_hung_task_detect_count++;
+ total_hung_task = sysctl_hung_task_detect_count - prev_detect_count;
trace_sched_process_hang(t);
- if (sysctl_hung_task_panic) {
+ if (sysctl_hung_task_panic && total_hung_task >= sysctl_hung_task_panic) {
console_verbose();
hung_task_show_lock = true;
hung_task_call_panic = true;
@@ -300,6 +304,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
int max_count = sysctl_hung_task_check_count;
unsigned long last_break = jiffies;
struct task_struct *g, *t;
+ unsigned long prev_detect_count = sysctl_hung_task_detect_count;
/*
* If the system crashed already then all bets are off,
@@ -320,7 +325,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
last_break = jiffies;
}
- check_hung_task(t, timeout);
+ check_hung_task(t, timeout, prev_detect_count);
}
unlock:
rcu_read_unlock();
@@ -389,7 +394,7 @@ static const struct ctl_table hung_task_sysctls[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
+ .extra2 = SYSCTL_INT_MAX,
},
{
.procname = "hung_task_check_count",
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 3034e294..3976c90 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1258,12 +1258,13 @@ config DEFAULT_HUNG_TASK_TIMEOUT
Keeping the default should be fine in most cases.
config BOOTPARAM_HUNG_TASK_PANIC
- bool "Panic (Reboot) On Hung Tasks"
+ int "Number of hung tasks to trigger kernel panic"
depends on DETECT_HUNG_TASK
+ default 0
help
- Say Y here to enable the kernel to panic on "hung tasks",
- which are bugs that cause the kernel to leave a task stuck
- in uninterruptible "D" state.
+ When set to a non-zero value, a kernel panic will be triggered
+ if the number of hung tasks found during a single scan reaches
+ this value.
The panic can be used in combination with panic_timeout,
to cause the system to reboot automatically after a
diff --git a/tools/testing/selftests/wireguard/qemu/kernel.config b/tools/testing/selftests/wireguard/qemu/kernel.config
index 936b18b..0504c11 100644
--- a/tools/testing/selftests/wireguard/qemu/kernel.config
+++ b/tools/testing/selftests/wireguard/qemu/kernel.config
@@ -81,7 +81,7 @@ CONFIG_WQ_WATCHDOG=y
CONFIG_DETECT_HUNG_TASK=y
CONFIG_BOOTPARAM_HARDLOCKUP_PANIC=y
CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y
-CONFIG_BOOTPARAM_HUNG_TASK_PANIC=y
+CONFIG_BOOTPARAM_HUNG_TASK_PANIC=1
CONFIG_PANIC_TIMEOUT=-1
CONFIG_STACKTRACE=y
CONFIG_EARLY_PRINTK=y
--
2.9.4
The previous implementation incorrectly assumed the original type of
'priv' was void**, leading to an unnecessary and misleading
cast. Correct the cast of the 'priv' pointer in test_dev_action() to
its actual type, long*, removing an unnecessary cast.
As an additional benefit, this fixes an out-of-bounds CHERI fault on
hardware with architectural capabilities. The original implementation
tried to store a capability-sized pointer using the 'priv'
pointer. However, the 'priv' pointer's capability only granted access
to the memory region of its original long type, leading to a bounds
violation since the size of a long is smaller than the size of a
capability. This change ensures that the pointer usage respects the
capabilities' bounds.
Signed-off-by: Florian Schmaus <florian.schmaus(a)codasip.com>
---
lib/kunit/kunit-test.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
index 8c01eabd4eaf..957b67818489 100644
--- a/lib/kunit/kunit-test.c
+++ b/lib/kunit/kunit-test.c
@@ -739,7 +739,7 @@ static struct kunit_case kunit_current_test_cases[] = {
static void test_dev_action(void *priv)
{
- *(void **)priv = (void *)1;
+ *(long*)priv = 1;
}
static void kunit_device_test(struct kunit *test)
--
2.51.0
Some high-level virtual drivers need to compute features from their
lower devices, but each currently has its own implementation and may
miss some feature computations. This patch set introduces a common function
to compute features for such devices.
Currently, bonding, team, and bridge have been updated to use the new
helper.
v4:
* update needed_{headroom, tailroom} in the common helper (Ido Schimmel)
* remove unneeded err in team (Stanislav Fomichev)
* remove selftest as `ethtool -k` does not test the dev->*_features. We
can add back the selftest when there is a good way to test. (Sabrina Dubroca)
v3:
a) fix hw_enc_features asign order (Sabrina Dubroca)
b) set virtual dev feature defination in netdev_features.h (Jakub Kicinski)
c) remove unneeded err in team_del_slave (Stanislav Fomichev)
d) remove NETIF_F_HW_ESP test as it needs to be test with GSO pkts (Sabrina Dubroca)
v2:
a) remove hard_header_len setting. I will set needed_headroom for bond/team
in a separate patch as bridge has it's own ways. (Ido Schimmel)
b) Add test file to Makefile, set RET=0 to a proper location. (Ido Schimmel)
Hangbin Liu (4):
net: add a common function to compute features from lowers devices
bonding: use common function to compute the features
team: use common function to compute the features
net: bridge: use common function to compute the features
drivers/net/bonding/bond_main.c | 99 ++-------------------------------
drivers/net/team/team_core.c | 83 ++-------------------------
include/linux/netdev_features.h | 18 ++++++
include/linux/netdevice.h | 1 +
net/bridge/br_if.c | 22 +-------
net/core/dev.c | 95 +++++++++++++++++++++++++++++++
6 files changed, 127 insertions(+), 191 deletions(-)
--
2.50.1
These patches are taken from the LUOv4 series [1] and address recent
comments from Pratyush.
This series refactors the KHO framework to better support in-kernel
users like the upcoming LUO. The current design, which relies on a
notifier chain and debugfs for control, is too restrictive for direct
programmatic use.
The core of this rework is the removal of the notifier chain in favor of
a direct registration API. This decouples clients from the shutdown-time
finalization sequence, allowing them to manage their preserved state
more flexibly and at any time.
In support of this new model, this series also:
- Exports kho_finalize() and kho_abort() for programmatic control.
- Makes the debugfs interface optional.
- Introduces APIs to unpreserve memory and fixes a bug in the abort
path where client state was being incorrectly discarded. Note that
this is an interim step, as a more comprehensive fix is planned as
part of the stateless KHO work [2].
- Moves all KHO code into a new kernel/liveupdate/ directory to
consolidate live update components.
[1] https://lore.kernel.org/all/20250929010321.3462457-1-pasha.tatashin@soleen.…
[2] https://lore.kernel.org/all/20251001011941.1513050-1-jasonmiu@google.com
Mike Rapoport (Microsoft) (1):
kho: drop notifiers
Pasha Tatashin (6):
kho: allow to drive kho from within kernel
kho: make debugfs interface optional
kho: add interfaces to unpreserve folios and page ranes
kho: don't unpreserve memory during abort
liveupdate: kho: move to kernel/liveupdate
kho: move kho debugfs directory to liveupdate
Documentation/core-api/kho/concepts.rst | 2 +-
MAINTAINERS | 3 +-
include/linux/kexec_handover.h | 53 +-
init/Kconfig | 2 +
kernel/Kconfig.kexec | 15 -
kernel/Makefile | 2 +-
kernel/liveupdate/Kconfig | 30 ++
kernel/liveupdate/Makefile | 4 +
kernel/{ => liveupdate}/kexec_handover.c | 515 ++++++++------------
kernel/liveupdate/kexec_handover_debug.c | 216 ++++++++
kernel/liveupdate/kexec_handover_internal.h | 47 ++
lib/test_kho.c | 30 +-
mm/memblock.c | 60 +--
tools/testing/selftests/kho/init.c | 2 +-
tools/testing/selftests/kho/vmtest.sh | 1 +
15 files changed, 553 insertions(+), 429 deletions(-)
create mode 100644 kernel/liveupdate/Kconfig
create mode 100644 kernel/liveupdate/Makefile
rename kernel/{ => liveupdate}/kexec_handover.c (79%)
create mode 100644 kernel/liveupdate/kexec_handover_debug.c
create mode 100644 kernel/liveupdate/kexec_handover_internal.h
base-commit: 4a71531471926e3c391665ee9c42f4e0295a4585
--
2.51.0.618.g983fd99d29-goog
On systems where the shmget() syscall is not supported, tests like
anon_page and shared_waitv will fail. Skip these tests in such cases to
allow the rest of the test suite to run.
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
---
tools/testing/selftests/futex/functional/futex_wait.c | 2 ++
tools/testing/selftests/futex/functional/futex_waitv.c | 2 ++
2 files changed, 4 insertions(+)
diff --git a/tools/testing/selftests/futex/functional/futex_wait.c b/tools/testing/selftests/futex/functional/futex_wait.c
index 152ca4612886..1269642bb662 100644
--- a/tools/testing/selftests/futex/functional/futex_wait.c
+++ b/tools/testing/selftests/futex/functional/futex_wait.c
@@ -71,6 +71,8 @@ TEST(anon_page)
/* Testing an anon page shared memory */
shm_id = shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666);
if (shm_id < 0) {
+ if (errno == ENOSYS)
+ ksft_exit_skip("shmget syscall not supported\n");
perror("shmget");
exit(1);
}
diff --git a/tools/testing/selftests/futex/functional/futex_waitv.c b/tools/testing/selftests/futex/functional/futex_waitv.c
index c684b10eb76e..3bc4e5dc70e7 100644
--- a/tools/testing/selftests/futex/functional/futex_waitv.c
+++ b/tools/testing/selftests/futex/functional/futex_waitv.c
@@ -86,6 +86,8 @@ TEST(shared_waitv)
int shm_id = shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666);
if (shm_id < 0) {
+ if (errno == ENOSYS)
+ ksft_exit_skip("shmget syscall not supported\n");
perror("shmget");
exit(1);
}
--
2.51.0.869.ge66316f041-goog
Basics and overview
===================
Software with larger attack surfaces (e.g. network facing apps like databases,
browsers or apps relying on browser runtimes) suffer from memory corruption
issues which can be utilized by attackers to bend control flow of the program
to eventually gain control (by making their payload executable). Attackers are
able to perform such attacks by leveraging call-sites which rely on indirect
calls or return sites which rely on obtaining return address from stack memory.
To mitigate such attacks, risc-v extension zicfilp enforces that all indirect
calls must land on a landing pad instruction `lpad` else cpu will raise software
check exception (a new cpu exception cause code on riscv).
Similarly for return flow, risc-v extension zicfiss extends architecture with
- `sspush` instruction to push return address on a shadow stack
- `sspopchk` instruction to pop return address from shadow stack
and compare with input operand (i.e. return address on stack)
- `sspopchk` to raise software check exception if comparision above
was a mismatch
- Protection mechanism using which shadow stack is not writeable via
regular store instructions
More information an details can be found at extensions github repo [1].
Equivalent to landing pad (zicfilp) on x86 is `ENDBRANCH` instruction in Intel
CET [3] and branch target identification (BTI) [4] on arm.
Similarly x86's Intel CET has shadow stack [5] and arm64 has guarded control
stack (GCS) [6] which are very similar to risc-v's zicfiss shadow stack.
x86 and arm64 support for user mode shadow stack is already in mainline.
Kernel awareness for user control flow integrity
================================================
This series picks up Samuel Holland's envcfg changes [2] as well. So if those are
being applied independently, they should be removed from this series.
Enabling:
In order to maintain compatibility and not break anything in user mode, kernel
doesn't enable control flow integrity cpu extensions on binary by default.
Instead exposes a prctl interface to enable, disable and lock the shadow stack
or landing pad feature for a task. This allows userspace (loader) to enumerate
if all objects in its address space are compiled with shadow stack and landing
pad support and accordingly enable the feature. Additionally if a subsequent
`dlopen` happens on a library, user mode can take a decision again to disable
the feature (if incoming library is not compiled with support) OR terminate the
task (if user mode policy is strict to have all objects in address space to be
compiled with control flow integirty cpu feature). prctl to enable shadow stack
results in allocating shadow stack from virtual memory and activating for user
address space. x86 and arm64 are also following same direction due to similar
reason(s).
clone/fork:
On clone and fork, cfi state for task is inherited by child. Shadow stack is
part of virtual memory and is a writeable memory from kernel perspective
(writeable via a restricted set of instructions aka shadow stack instructions)
Thus kernel changes ensure that this memory is converted into read-only when
fork/clone happens and COWed when fault is taken due to sspush, sspopchk or
ssamoswap. In case `CLONE_VM` is specified and shadow stack is to be enabled,
kernel will automatically allocate a shadow stack for that clone call.
map_shadow_stack:
x86 introduced `map_shadow_stack` system call to allow user space to explicitly
map shadow stack memory in its address space. It is useful to allocate shadow
for different contexts managed by a single thread (green threads or contexts)
risc-v implements this system call as well.
signal management:
If shadow stack is enabled for a task, kernel performs an asynchronous control
flow diversion to deliver the signal and eventually expects userspace to issue
sigreturn so that original execution can be resumed. Even though resume context
is prepared by kernel, it is in user space memory and is subject to memory
corruption and corruption bugs can be utilized by attacker in this race window
to perform arbitrary sigreturn and eventually bypass cfi mechanism.
Another issue is how to ensure that cfi related state on sigcontext area is not
trampled by legacy apps or apps compiled with old kernel headers.
In order to mitigate control-flow hijacting, kernel prepares a token and place
it on shadow stack before signal delivery and places address of token in
sigcontext structure. During sigreturn, kernel obtains address of token from
sigcontext struture, reads token from shadow stack and validates it and only
then allow sigreturn to succeed. Compatiblity issue is solved by adopting
dynamic sigcontext management introduced for vector extension. This series
re-factor the code little bit to allow future sigcontext management easy (as
proposed by Andy Chiu from SiFive)
config and compilation:
Introduce a new risc-v config option `CONFIG_RISCV_USER_CFI`. Selecting this
config option picks the kernel support for user control flow integrity. This
optin is presented only if toolchain has shadow stack and landing pad support.
And is on purpose guarded by toolchain support. Reason being that eventually
vDSO also needs to be compiled in with shadow stack and landing pad support.
vDSO compile patches are not included as of now because landing pad labeling
scheme is yet to settle for usermode runtime.
To get more information on kernel interactions with respect to
zicfilp and zicfiss, patch series adds documentation for
`zicfilp` and `zicfiss` in following:
Documentation/arch/riscv/zicfiss.rst
Documentation/arch/riscv/zicfilp.rst
How to test this series
=======================
Toolchain
---------
$ git clone git@github.com:sifive/riscv-gnu-toolchain.git -b cfi-dev
$ riscv-gnu-toolchain/configure --prefix=<path-to-where-to-build> --with-arch=rv64gc_zicfilp_zicfiss --enable-linux --disable-gdb --with-extra-multilib-test="rv64gc_zicfilp_zicfiss-lp64d:-static"
$ make -j$(nproc)
Qemu
----
Get the lastest qemu
$ cd qemu
$ mkdir build
$ cd build
$ ../configure --target-list=riscv64-softmmu
$ make -j$(nproc)
Opensbi
-------
$ git clone git@github.com:deepak0414/opensbi.git -b v6_cfi_spec_split_opensbi
$ make CROSS_COMPILE=<your riscv toolchain> -j$(nproc) PLATFORM=generic
Linux
-----
Running defconfig is fine. CFI is enabled by default if the toolchain
supports it.
$ make ARCH=riscv CROSS_COMPILE=<path-to-cfi-riscv-gnu-toolchain>/build/bin/riscv64-unknown-linux-gnu- -j$(nproc) defconfig
$ make ARCH=riscv CROSS_COMPILE=<path-to-cfi-riscv-gnu-toolchain>/build/bin/riscv64-unknown-linux-gnu- -j$(nproc)
Running
-------
Modify your qemu command to have:
-bios <path-to-cfi-opensbi>/build/platform/generic/firmware/fw_dynamic.bin
-cpu rv64,zicfilp=true,zicfiss=true,zimop=true,zcmop=true
References
==========
[1] - https://github.com/riscv/riscv-cfi
[2] - https://lore.kernel.org/all/20240814081126.956287-1-samuel.holland@sifive.c…
[3] - https://lwn.net/Articles/889475/
[4] - https://developer.arm.com/documentation/109576/0100/Branch-Target-Identific…
[5] - https://www.intel.com/content/dam/develop/external/us/en/documents/catc17-i…
[6] - https://lwn.net/Articles/940403/
To: Thomas Gleixner <tglx(a)linutronix.de>
To: Ingo Molnar <mingo(a)redhat.com>
To: Borislav Petkov <bp(a)alien8.de>
To: Dave Hansen <dave.hansen(a)linux.intel.com>
To: x86(a)kernel.org
To: H. Peter Anvin <hpa(a)zytor.com>
To: Andrew Morton <akpm(a)linux-foundation.org>
To: Liam R. Howlett <Liam.Howlett(a)oracle.com>
To: Vlastimil Babka <vbabka(a)suse.cz>
To: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
To: Paul Walmsley <paul.walmsley(a)sifive.com>
To: Palmer Dabbelt <palmer(a)dabbelt.com>
To: Albert Ou <aou(a)eecs.berkeley.edu>
To: Conor Dooley <conor(a)kernel.org>
To: Rob Herring <robh(a)kernel.org>
To: Krzysztof Kozlowski <krzk+dt(a)kernel.org>
To: Arnd Bergmann <arnd(a)arndb.de>
To: Christian Brauner <brauner(a)kernel.org>
To: Peter Zijlstra <peterz(a)infradead.org>
To: Oleg Nesterov <oleg(a)redhat.com>
To: Eric Biederman <ebiederm(a)xmission.com>
To: Kees Cook <kees(a)kernel.org>
To: Jonathan Corbet <corbet(a)lwn.net>
To: Shuah Khan <shuah(a)kernel.org>
To: Jann Horn <jannh(a)google.com>
To: Conor Dooley <conor+dt(a)kernel.org>
To: Miguel Ojeda <ojeda(a)kernel.org>
To: Alex Gaynor <alex.gaynor(a)gmail.com>
To: Boqun Feng <boqun.feng(a)gmail.com>
To: Gary Guo <gary(a)garyguo.net>
To: Björn Roy Baron <bjorn3_gh(a)protonmail.com>
To: Benno Lossin <benno.lossin(a)proton.me>
To: Andreas Hindborg <a.hindborg(a)kernel.org>
To: Alice Ryhl <aliceryhl(a)google.com>
To: Trevor Gross <tmgross(a)umich.edu>
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-fsdevel(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Cc: linux-riscv(a)lists.infradead.org
Cc: devicetree(a)vger.kernel.org
Cc: linux-arch(a)vger.kernel.org
Cc: linux-doc(a)vger.kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Cc: alistair.francis(a)wdc.com
Cc: richard.henderson(a)linaro.org
Cc: jim.shu(a)sifive.com
Cc: andybnac(a)gmail.com
Cc: kito.cheng(a)sifive.com
Cc: charlie(a)rivosinc.com
Cc: atishp(a)rivosinc.com
Cc: evan(a)rivosinc.com
Cc: cleger(a)rivosinc.com
Cc: alexghiti(a)rivosinc.com
Cc: samitolvanen(a)google.com
Cc: broonie(a)kernel.org
Cc: rick.p.edgecombe(a)intel.com
Cc: rust-for-linux(a)vger.kernel.org
changelog
---------
v20:
- rebased on v6.18-rc1.
- Added two vDSO support. If `CONFIG_RISCV_USER_CFI` is selected
two vDSOs are compiled (one for hardware prior to RVA23 and one
for RVA23 onwards). Kernel exposes RVA23 vDSO if hardware/cpu
implements zimop else exposes existing vDSO to userspace.
- default selection for `CONFIG_RISCV_USER_CFI` is "Yes".
- replaced "__ASSEMBLY__" with "__ASSEMBLER__"
v19:
- riscv_nousercfi was `int`. changed it to unsigned long.
Thanks to Alex Ghiti for reporting it. It was a bug.
- ELP is cleared on trap entry only when CONFIG_64BIT.
- restore ssp back on return to usermode was being done
before `riscv_v_context_nesting_end` on trap exit path.
If kernel shadow stack were enabled this would result in
kernel operating on user shadow stack and panic (as I found
in my testing of kcfi patch series). So fixed that.
v18:
- rebased on 6.16-rc1
- uprobe handling clears ELP in sstatus image in pt_regs
- vdso was missing shadow stack elf note for object files.
added that. Additional asm file for vdso needed the elf marker
flag. toolchain should complain if `-fcf-protection=full` and
marker is missing for object generated from asm file. Asked
toolchain folks to fix this. Although no reason to gate the merge
on that.
- Split up compile options for march and fcf-protection in vdso
Makefile
- CONFIG_RISCV_USER_CFI option is moved under "Kernel features" menu
Added `arch/riscv/configs/hardening.config` fragment which selects
CONFIG_RISCV_USER_CFI
v17:
- fixed warnings due to empty macros in usercfi.h (reported by alexg)
- fixed prefixes in commit titles reported by alexg
- took below uprobe with fcfi v2 patch from Zong Li and squashed it with
"riscv/traps: Introduce software check exception and uprobe handling"
https://lore.kernel.org/all/20250604093403.10916-1-zong.li@sifive.com/
v16:
- If FWFT is not implemented or returns error for shadow stack activation, then
no_usercfi is set to disable shadow stack. Although this should be picked up
by extension validation and activation. Fixed this bug for zicfilp and zicfiss
both. Thanks to Charlie Jenkins for reporting this.
- If toolchain doesn't support cfi, cfi kselftest shouldn't build. Suggested by
Charlie Jenkins.
- Default for CONFIG_RISCV_USER_CFI is set to no. Charlie/Atish suggested to
keep it off till we have more hardware availibility with RVA23 profile and
zimop/zcmop implemented. Else this will start breaking people's workflow
- Includes the fix if "!RV64 and !SBI" then definitions for FWFT in
asm-offsets.c error.
v15:
- Toolchain has been updated to include `-fcf-protection` flag. This
exists for x86 as well. Updated kernel patches to compile vDSO and
selftest to compile with `fcf-protection=full` flag.
- selecting CONFIG_RISCV_USERCFI selects CONFIG_RISCV_SBI.
- Patch to enable shadow stack for kernel wasn't hidden behind
CONFIG_RISCV_USERCFI and CONFIG_RISCV_SBI. fixed that.
v14:
- rebased on top of palmer/sbi-v3. Thus dropped clement's FWFT patches
Updated RISCV_ISA_EXT_XXXX in hwcap and hwprobe constants.
- Took Radim's suggestions on bitfields.
- Placed cfi_state at the end of thread_info block so that current situation
is not disturbed with respect to member fields of thread_info in single
cacheline.
v13:
- cpu_supports_shadow_stack/cpu_supports_indirect_br_lp_instr uses
riscv_has_extension_unlikely()
- uses nops(count) to create nop slide
- RISCV_ACQUIRE_BARRIER is not needed in `amo_user_shstk`. Removed it
- changed ternaries to simply use implicit casting to convert to bool.
- kernel command line allows to disable zicfilp and zicfiss independently.
updated kernel-parameters.txt.
- ptrace user abi for cfi uses bitmasks instead of bitfields. Added ptrace
kselftest.
- cosmetic and grammatical changes to documentation.
v12:
- It seems like I had accidently squashed arch agnostic indirect branch
tracking prctl and riscv implementation of those prctls. Split them again.
- set_shstk_status/set_indir_lp_status perform CSR writes only when CPU
support is available. As suggested by Zong Li.
- Some minor clean up in kselftests as suggested by Zong Li.
v11:
- patch "arch/riscv: compile vdso with landing pad" was unconditionally
selecting `_zicfilp` for vDSO compile. fixed that. Changed `lpad 1` to
to `lpad 0`.
v10:
- dropped "mm: helper `is_shadow_stack_vma` to check shadow stack vma". This patch
is not that interesting to this patch series for risc-v. There are instances in
arch directories where VM_SHADOW_STACK flag is anyways used. Dropping this patch
to expedite merging in riscv tree.
- Took suggestions from `Clement` on "riscv: zicfiss / zicfilp enumeration" to
validate presence of cfi based on config.
- Added a patch for vDSO to have `lpad 0`. I had omitted this earlier to make sure
we add single vdso object with cfi enabled. But a vdso object with scheme of
zero labeled landing pad is least common denominator and should work with all
objects of zero labeled as well as function-signature labeled objects.
v9:
- rebased on master (39a803b754d5 fix braino in "9p: fix ->rename_sem exclusion")
- dropped "mm: Introduce ARCH_HAS_USER_SHADOW_STACK" (master has it from arm64/gcs)
- dropped "prctl: arch-agnostic prctl for shadow stack" (master has it from arm64/gcs)
v8:
- rebased on palmer/for-next
- dropped samuel holland's `envcfg` context switch patches.
they are in parlmer/for-next
v7:
- Removed "riscv/Kconfig: enable HAVE_EXIT_THREAD for riscv"
Instead using `deactivate_mm` flow to clean up.
see here for more context
https://lore.kernel.org/all/20230908203655.543765-1-rick.p.edgecombe@intel.…
- Changed the header include in `kselftest`. Hopefully this fixes compile
issue faced by Zong Li at SiFive.
- Cleaned up an orphaned change to `mm/mmap.c` in below patch
"riscv/mm : ensure PROT_WRITE leads to VM_READ | VM_WRITE"
- Lock interfaces for shadow stack and indirect branch tracking expect arg == 0
Any future evolution of this interface should accordingly define how arg should
be setup.
- `mm/map.c` has an instance of using `VM_SHADOW_STACK`. Fixed it to use helper
`is_shadow_stack_vma`.
- Link to v6: https://lore.kernel.org/r/20241008-v5_user_cfi_series-v6-0-60d9fe073f37@riv…
v6:
- Picked up Samuel Holland's changes as is with `envcfg` placed in
`thread` instead of `thread_info`
- fixed unaligned newline escapes in kselftest
- cleaned up messages in kselftest and included test output in commit message
- fixed a bug in clone path reported by Zong Li
- fixed a build issue if CONFIG_RISCV_ISA_V is not selected
(this was introduced due to re-factoring signal context
management code)
v5:
- rebased on v6.12-rc1
- Fixed schema related issues in device tree file
- Fixed some of the documentation related issues in zicfilp/ss.rst
(style issues and added index)
- added `SHADOW_STACK_SET_MARKER` so that implementation can define base
of shadow stack.
- Fixed warnings on definitions added in usercfi.h when
CONFIG_RISCV_USER_CFI is not selected.
- Adopted context header based signal handling as proposed by Andy Chiu
- Added support for enabling kernel mode access to shadow stack using
FWFT
(https://github.com/riscv-non-isa/riscv-sbi-doc/blob/master/src/ext-firmware…)
- Link to v5: https://lore.kernel.org/r/20241001-v5_user_cfi_series-v1-0-3ba65b6e550f@riv…
(Note: I had an issue in my workflow due to which version number wasn't
picked up correctly while sending out patches)
v4:
- rebased on 6.11-rc6
- envcfg: Converged with Samuel Holland's patches for envcfg management on per-
thread basis.
- vma_is_shadow_stack is renamed to is_vma_shadow_stack
- picked up Mark Brown's `ARCH_HAS_USER_SHADOW_STACK` patch
- signal context: using extended context management to maintain compatibility.
- fixed `-Wmissing-prototypes` compiler warnings for prctl functions
- Documentation fixes and amending typos.
- Link to v4: https://lore.kernel.org/all/20240912231650.3740732-1-debug@rivosinc.com/
v3:
- envcfg
logic to pick up base envcfg had a bug where `ENVCFG_CBZE` could have been
picked on per task basis, even though CPU didn't implement it. Fixed in
this series.
- dt-bindings
As suggested, split into separate commit. fixed the messaging that spec is
in public review
- arch_is_shadow_stack change
arch_is_shadow_stack changed to vma_is_shadow_stack
- hwprobe
zicfiss / zicfilp if present will get enumerated in hwprobe
- selftests
As suggested, added object and binary filenames to .gitignore
Selftest binary anyways need to be compiled with cfi enabled compiler which
will make sure that landing pad and shadow stack are enabled. Thus removed
separate enable/disable tests. Cleaned up tests a bit.
- Link to v3: https://lore.kernel.org/lkml/20240403234054.2020347-1-debug@rivosinc.com/
v2:
- Using config `CONFIG_RISCV_USER_CFI`, kernel support for riscv control flow
integrity for user mode programs can be compiled in the kernel.
- Enabling of control flow integrity for user programs is left to user runtime
- This patch series introduces arch agnostic `prctls` to enable shadow stack
and indirect branch tracking. And implements them on riscv.
---
Changes in v20:
- Link to v19: https://lore.kernel.org/r/20250731-v5_user_cfi_series-v19-0-09b468d7beab@ri…
Changes in v19:
- Link to v18: https://lore.kernel.org/r/20250711-v5_user_cfi_series-v18-0-a8ee62f9f38e@ri…
Changes in v18:
- Link to v17: https://lore.kernel.org/r/20250604-v5_user_cfi_series-v17-0-4565c2cf869f@ri…
Changes in v17:
- Link to v16: https://lore.kernel.org/r/20250522-v5_user_cfi_series-v16-0-64f61a35eee7@ri…
Changes in v16:
- Link to v15: https://lore.kernel.org/r/20250502-v5_user_cfi_series-v15-0-914966471885@ri…
Changes in v15:
- changelog posted just below cover letter
- Link to v14: https://lore.kernel.org/r/20250429-v5_user_cfi_series-v14-0-5239410d012a@ri…
Changes in v14:
- changelog posted just below cover letter
- Link to v13: https://lore.kernel.org/r/20250424-v5_user_cfi_series-v13-0-971437de586a@ri…
Changes in v13:
- changelog posted just below cover letter
- Link to v12: https://lore.kernel.org/r/20250314-v5_user_cfi_series-v12-0-e51202b53138@ri…
Changes in v12:
- changelog posted just below cover letter
- Link to v11: https://lore.kernel.org/r/20250310-v5_user_cfi_series-v11-0-86b36cbfb910@ri…
Changes in v11:
- changelog posted just below cover letter
- Link to v10: https://lore.kernel.org/r/20250210-v5_user_cfi_series-v10-0-163dcfa31c60@ri…
---
Andy Chiu (1):
riscv: signal: abstract header saving for setup_sigcontext
Deepak Gupta (26):
mm: VM_SHADOW_STACK definition for riscv
dt-bindings: riscv: zicfilp and zicfiss in dt-bindings (extensions.yaml)
riscv: zicfiss / zicfilp enumeration
riscv: zicfiss / zicfilp extension csr and bit definitions
riscv: usercfi state for task and save/restore of CSR_SSP on trap entry/exit
riscv/mm : ensure PROT_WRITE leads to VM_READ | VM_WRITE
riscv/mm: manufacture shadow stack pte
riscv/mm: teach pte_mkwrite to manufacture shadow stack PTEs
riscv/mm: write protect and shadow stack
riscv/mm: Implement map_shadow_stack() syscall
riscv/shstk: If needed allocate a new shadow stack on clone
riscv: Implements arch agnostic shadow stack prctls
prctl: arch-agnostic prctl for indirect branch tracking
riscv: Implements arch agnostic indirect branch tracking prctls
riscv/traps: Introduce software check exception and uprobe handling
riscv/signal: save and restore of shadow stack for signal
riscv/kernel: update __show_regs to print shadow stack register
riscv/ptrace: riscv cfi status and state via ptrace and in core files
riscv/hwprobe: zicfilp / zicfiss enumeration in hwprobe
riscv: kernel command line option to opt out of user cfi
riscv: enable kernel access to shadow stack memory via FWFT sbi call
arch/riscv: dual vdso creation logic and select vdso based on hw
riscv: create a config for shadow stack and landing pad instr support
riscv: Documentation for landing pad / indirect branch tracking
riscv: Documentation for shadow stack on riscv
kselftest/riscv: kselftest for user mode cfi
Jim Shu (1):
arch/riscv: compile vdso with landing pad and shadow stack note
Documentation/admin-guide/kernel-parameters.txt | 8 +
Documentation/arch/riscv/index.rst | 2 +
Documentation/arch/riscv/zicfilp.rst | 115 +++++
Documentation/arch/riscv/zicfiss.rst | 179 +++++++
.../devicetree/bindings/riscv/extensions.yaml | 14 +
arch/riscv/Kconfig | 21 +
arch/riscv/Makefile | 8 +-
arch/riscv/configs/hardening.config | 4 +
arch/riscv/include/asm/asm-prototypes.h | 1 +
arch/riscv/include/asm/assembler.h | 44 ++
arch/riscv/include/asm/cpufeature.h | 12 +
arch/riscv/include/asm/csr.h | 16 +
arch/riscv/include/asm/entry-common.h | 2 +
arch/riscv/include/asm/hwcap.h | 2 +
arch/riscv/include/asm/mman.h | 26 +
arch/riscv/include/asm/mmu_context.h | 7 +
arch/riscv/include/asm/pgtable.h | 30 +-
arch/riscv/include/asm/processor.h | 1 +
arch/riscv/include/asm/thread_info.h | 3 +
arch/riscv/include/asm/usercfi.h | 95 ++++
arch/riscv/include/asm/vdso.h | 7 +-
arch/riscv/include/asm/vector.h | 3 +
arch/riscv/include/uapi/asm/hwprobe.h | 2 +
arch/riscv/include/uapi/asm/ptrace.h | 34 ++
arch/riscv/include/uapi/asm/sigcontext.h | 1 +
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/asm-offsets.c | 10 +
arch/riscv/kernel/cpufeature.c | 27 +
arch/riscv/kernel/entry.S | 38 ++
arch/riscv/kernel/head.S | 27 +
arch/riscv/kernel/process.c | 27 +-
arch/riscv/kernel/ptrace.c | 95 ++++
arch/riscv/kernel/signal.c | 148 +++++-
arch/riscv/kernel/sys_hwprobe.c | 2 +
arch/riscv/kernel/sys_riscv.c | 10 +
arch/riscv/kernel/traps.c | 54 ++
arch/riscv/kernel/usercfi.c | 545 +++++++++++++++++++++
arch/riscv/kernel/vdso.c | 7 +
arch/riscv/kernel/vdso/Makefile | 40 +-
arch/riscv/kernel/vdso/flush_icache.S | 4 +
arch/riscv/kernel/vdso/gen_vdso_offsets.sh | 4 +-
arch/riscv/kernel/vdso/getcpu.S | 4 +
arch/riscv/kernel/vdso/note.S | 3 +
arch/riscv/kernel/vdso/rt_sigreturn.S | 4 +
arch/riscv/kernel/vdso/sys_hwprobe.S | 4 +
arch/riscv/kernel/vdso/vgetrandom-chacha.S | 5 +-
arch/riscv/kernel/vdso_cfi/Makefile | 25 +
arch/riscv/kernel/vdso_cfi/vdso-cfi.S | 11 +
arch/riscv/mm/init.c | 2 +-
arch/riscv/mm/pgtable.c | 16 +
include/linux/cpu.h | 4 +
include/linux/mm.h | 7 +
include/uapi/linux/elf.h | 2 +
include/uapi/linux/prctl.h | 27 +
kernel/sys.c | 30 ++
tools/testing/selftests/riscv/Makefile | 2 +-
tools/testing/selftests/riscv/cfi/.gitignore | 3 +
tools/testing/selftests/riscv/cfi/Makefile | 16 +
tools/testing/selftests/riscv/cfi/cfi_rv_test.h | 82 ++++
tools/testing/selftests/riscv/cfi/riscv_cfi_test.c | 173 +++++++
tools/testing/selftests/riscv/cfi/shadowstack.c | 385 +++++++++++++++
tools/testing/selftests/riscv/cfi/shadowstack.h | 27 +
62 files changed, 2468 insertions(+), 41 deletions(-)
---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20240930-v5_user_cfi_series-3dc332f8f5b2
--
- debug
v21: fixed build errors.
Basics and overview
===================
Software with larger attack surfaces (e.g. network facing apps like databases,
browsers or apps relying on browser runtimes) suffer from memory corruption
issues which can be utilized by attackers to bend control flow of the program
to eventually gain control (by making their payload executable). Attackers are
able to perform such attacks by leveraging call-sites which rely on indirect
calls or return sites which rely on obtaining return address from stack memory.
To mitigate such attacks, risc-v extension zicfilp enforces that all indirect
calls must land on a landing pad instruction `lpad` else cpu will raise software
check exception (a new cpu exception cause code on riscv).
Similarly for return flow, risc-v extension zicfiss extends architecture with
- `sspush` instruction to push return address on a shadow stack
- `sspopchk` instruction to pop return address from shadow stack
and compare with input operand (i.e. return address on stack)
- `sspopchk` to raise software check exception if comparision above
was a mismatch
- Protection mechanism using which shadow stack is not writeable via
regular store instructions
More information an details can be found at extensions github repo [1].
Equivalent to landing pad (zicfilp) on x86 is `ENDBRANCH` instruction in Intel
CET [3] and branch target identification (BTI) [4] on arm.
Similarly x86's Intel CET has shadow stack [5] and arm64 has guarded control
stack (GCS) [6] which are very similar to risc-v's zicfiss shadow stack.
x86 and arm64 support for user mode shadow stack is already in mainline.
Kernel awareness for user control flow integrity
================================================
This series picks up Samuel Holland's envcfg changes [2] as well. So if those are
being applied independently, they should be removed from this series.
Enabling:
In order to maintain compatibility and not break anything in user mode, kernel
doesn't enable control flow integrity cpu extensions on binary by default.
Instead exposes a prctl interface to enable, disable and lock the shadow stack
or landing pad feature for a task. This allows userspace (loader) to enumerate
if all objects in its address space are compiled with shadow stack and landing
pad support and accordingly enable the feature. Additionally if a subsequent
`dlopen` happens on a library, user mode can take a decision again to disable
the feature (if incoming library is not compiled with support) OR terminate the
task (if user mode policy is strict to have all objects in address space to be
compiled with control flow integirty cpu feature). prctl to enable shadow stack
results in allocating shadow stack from virtual memory and activating for user
address space. x86 and arm64 are also following same direction due to similar
reason(s).
clone/fork:
On clone and fork, cfi state for task is inherited by child. Shadow stack is
part of virtual memory and is a writeable memory from kernel perspective
(writeable via a restricted set of instructions aka shadow stack instructions)
Thus kernel changes ensure that this memory is converted into read-only when
fork/clone happens and COWed when fault is taken due to sspush, sspopchk or
ssamoswap. In case `CLONE_VM` is specified and shadow stack is to be enabled,
kernel will automatically allocate a shadow stack for that clone call.
map_shadow_stack:
x86 introduced `map_shadow_stack` system call to allow user space to explicitly
map shadow stack memory in its address space. It is useful to allocate shadow
for different contexts managed by a single thread (green threads or contexts)
risc-v implements this system call as well.
signal management:
If shadow stack is enabled for a task, kernel performs an asynchronous control
flow diversion to deliver the signal and eventually expects userspace to issue
sigreturn so that original execution can be resumed. Even though resume context
is prepared by kernel, it is in user space memory and is subject to memory
corruption and corruption bugs can be utilized by attacker in this race window
to perform arbitrary sigreturn and eventually bypass cfi mechanism.
Another issue is how to ensure that cfi related state on sigcontext area is not
trampled by legacy apps or apps compiled with old kernel headers.
In order to mitigate control-flow hijacting, kernel prepares a token and place
it on shadow stack before signal delivery and places address of token in
sigcontext structure. During sigreturn, kernel obtains address of token from
sigcontext struture, reads token from shadow stack and validates it and only
then allow sigreturn to succeed. Compatiblity issue is solved by adopting
dynamic sigcontext management introduced for vector extension. This series
re-factor the code little bit to allow future sigcontext management easy (as
proposed by Andy Chiu from SiFive)
config and compilation:
Introduce a new risc-v config option `CONFIG_RISCV_USER_CFI`. Selecting this
config option picks the kernel support for user control flow integrity. This
optin is presented only if toolchain has shadow stack and landing pad support.
And is on purpose guarded by toolchain support. Reason being that eventually
vDSO also needs to be compiled in with shadow stack and landing pad support.
vDSO compile patches are not included as of now because landing pad labeling
scheme is yet to settle for usermode runtime.
To get more information on kernel interactions with respect to
zicfilp and zicfiss, patch series adds documentation for
`zicfilp` and `zicfiss` in following:
Documentation/arch/riscv/zicfiss.rst
Documentation/arch/riscv/zicfilp.rst
How to test this series
=======================
Toolchain
---------
$ git clone git@github.com:sifive/riscv-gnu-toolchain.git -b cfi-dev
$ riscv-gnu-toolchain/configure --prefix=<path-to-where-to-build> --with-arch=rv64gc_zicfilp_zicfiss --enable-linux --disable-gdb --with-extra-multilib-test="rv64gc_zicfilp_zicfiss-lp64d:-static"
$ make -j$(nproc)
Qemu
----
Get the lastest qemu
$ cd qemu
$ mkdir build
$ cd build
$ ../configure --target-list=riscv64-softmmu
$ make -j$(nproc)
Opensbi
-------
$ git clone git@github.com:deepak0414/opensbi.git -b v6_cfi_spec_split_opensbi
$ make CROSS_COMPILE=<your riscv toolchain> -j$(nproc) PLATFORM=generic
Linux
-----
Running defconfig is fine. CFI is enabled by default if the toolchain
supports it.
$ make ARCH=riscv CROSS_COMPILE=<path-to-cfi-riscv-gnu-toolchain>/build/bin/riscv64-unknown-linux-gnu- -j$(nproc) defconfig
$ make ARCH=riscv CROSS_COMPILE=<path-to-cfi-riscv-gnu-toolchain>/build/bin/riscv64-unknown-linux-gnu- -j$(nproc)
Running
-------
Modify your qemu command to have:
-bios <path-to-cfi-opensbi>/build/platform/generic/firmware/fw_dynamic.bin
-cpu rv64,zicfilp=true,zicfiss=true,zimop=true,zcmop=true
References
==========
[1] - https://github.com/riscv/riscv-cfi
[2] - https://lore.kernel.org/all/20240814081126.956287-1-samuel.holland@sifive.c…
[3] - https://lwn.net/Articles/889475/
[4] - https://developer.arm.com/documentation/109576/0100/Branch-Target-Identific…
[5] - https://www.intel.com/content/dam/develop/external/us/en/documents/catc17-i…
[6] - https://lwn.net/Articles/940403/
To: Thomas Gleixner <tglx(a)linutronix.de>
To: Ingo Molnar <mingo(a)redhat.com>
To: Borislav Petkov <bp(a)alien8.de>
To: Dave Hansen <dave.hansen(a)linux.intel.com>
To: x86(a)kernel.org
To: H. Peter Anvin <hpa(a)zytor.com>
To: Andrew Morton <akpm(a)linux-foundation.org>
To: Liam R. Howlett <Liam.Howlett(a)oracle.com>
To: Vlastimil Babka <vbabka(a)suse.cz>
To: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
To: Paul Walmsley <paul.walmsley(a)sifive.com>
To: Palmer Dabbelt <palmer(a)dabbelt.com>
To: Albert Ou <aou(a)eecs.berkeley.edu>
To: Conor Dooley <conor(a)kernel.org>
To: Rob Herring <robh(a)kernel.org>
To: Krzysztof Kozlowski <krzk+dt(a)kernel.org>
To: Arnd Bergmann <arnd(a)arndb.de>
To: Christian Brauner <brauner(a)kernel.org>
To: Peter Zijlstra <peterz(a)infradead.org>
To: Oleg Nesterov <oleg(a)redhat.com>
To: Eric Biederman <ebiederm(a)xmission.com>
To: Kees Cook <kees(a)kernel.org>
To: Jonathan Corbet <corbet(a)lwn.net>
To: Shuah Khan <shuah(a)kernel.org>
To: Jann Horn <jannh(a)google.com>
To: Conor Dooley <conor+dt(a)kernel.org>
To: Miguel Ojeda <ojeda(a)kernel.org>
To: Alex Gaynor <alex.gaynor(a)gmail.com>
To: Boqun Feng <boqun.feng(a)gmail.com>
To: Gary Guo <gary(a)garyguo.net>
To: Björn Roy Baron <bjorn3_gh(a)protonmail.com>
To: Benno Lossin <benno.lossin(a)proton.me>
To: Andreas Hindborg <a.hindborg(a)kernel.org>
To: Alice Ryhl <aliceryhl(a)google.com>
To: Trevor Gross <tmgross(a)umich.edu>
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-fsdevel(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Cc: linux-riscv(a)lists.infradead.org
Cc: devicetree(a)vger.kernel.org
Cc: linux-arch(a)vger.kernel.org
Cc: linux-doc(a)vger.kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Cc: alistair.francis(a)wdc.com
Cc: richard.henderson(a)linaro.org
Cc: jim.shu(a)sifive.com
Cc: andybnac(a)gmail.com
Cc: kito.cheng(a)sifive.com
Cc: charlie(a)rivosinc.com
Cc: atishp(a)rivosinc.com
Cc: evan(a)rivosinc.com
Cc: cleger(a)rivosinc.com
Cc: alexghiti(a)rivosinc.com
Cc: samitolvanen(a)google.com
Cc: broonie(a)kernel.org
Cc: rick.p.edgecombe(a)intel.com
Cc: rust-for-linux(a)vger.kernel.org
changelog
---------
v21:
- Fixing build errors due to changes in arch/riscv/include/asm/vdso.h
Using #ifdef instead of IS_ENABLED in arch/riscv/include/asm/vdso.h
vdso-cfi-offsets.h should be included only when CONFIG_RISCV_USER_CFI
is selected.
v20:
- rebased on v6.18-rc1.
- Added two vDSO support. If `CONFIG_RISCV_USER_CFI` is selected
two vDSOs are compiled (one for hardware prior to RVA23 and one
for RVA23 onwards). Kernel exposes RVA23 vDSO if hardware/cpu
implements zimop else exposes existing vDSO to userspace.
- default selection for `CONFIG_RISCV_USER_CFI` is "Yes".
- replaced "__ASSEMBLY__" with "__ASSEMBLER__"
v19:
- riscv_nousercfi was `int`. changed it to unsigned long.
Thanks to Alex Ghiti for reporting it. It was a bug.
- ELP is cleared on trap entry only when CONFIG_64BIT.
- restore ssp back on return to usermode was being done
before `riscv_v_context_nesting_end` on trap exit path.
If kernel shadow stack were enabled this would result in
kernel operating on user shadow stack and panic (as I found
in my testing of kcfi patch series). So fixed that.
v18:
- rebased on 6.16-rc1
- uprobe handling clears ELP in sstatus image in pt_regs
- vdso was missing shadow stack elf note for object files.
added that. Additional asm file for vdso needed the elf marker
flag. toolchain should complain if `-fcf-protection=full` and
marker is missing for object generated from asm file. Asked
toolchain folks to fix this. Although no reason to gate the merge
on that.
- Split up compile options for march and fcf-protection in vdso
Makefile
- CONFIG_RISCV_USER_CFI option is moved under "Kernel features" menu
Added `arch/riscv/configs/hardening.config` fragment which selects
CONFIG_RISCV_USER_CFI
v17:
- fixed warnings due to empty macros in usercfi.h (reported by alexg)
- fixed prefixes in commit titles reported by alexg
- took below uprobe with fcfi v2 patch from Zong Li and squashed it with
"riscv/traps: Introduce software check exception and uprobe handling"
https://lore.kernel.org/all/20250604093403.10916-1-zong.li@sifive.com/
v16:
- If FWFT is not implemented or returns error for shadow stack activation, then
no_usercfi is set to disable shadow stack. Although this should be picked up
by extension validation and activation. Fixed this bug for zicfilp and zicfiss
both. Thanks to Charlie Jenkins for reporting this.
- If toolchain doesn't support cfi, cfi kselftest shouldn't build. Suggested by
Charlie Jenkins.
- Default for CONFIG_RISCV_USER_CFI is set to no. Charlie/Atish suggested to
keep it off till we have more hardware availibility with RVA23 profile and
zimop/zcmop implemented. Else this will start breaking people's workflow
- Includes the fix if "!RV64 and !SBI" then definitions for FWFT in
asm-offsets.c error.
v15:
- Toolchain has been updated to include `-fcf-protection` flag. This
exists for x86 as well. Updated kernel patches to compile vDSO and
selftest to compile with `fcf-protection=full` flag.
- selecting CONFIG_RISCV_USERCFI selects CONFIG_RISCV_SBI.
- Patch to enable shadow stack for kernel wasn't hidden behind
CONFIG_RISCV_USERCFI and CONFIG_RISCV_SBI. fixed that.
v14:
- rebased on top of palmer/sbi-v3. Thus dropped clement's FWFT patches
Updated RISCV_ISA_EXT_XXXX in hwcap and hwprobe constants.
- Took Radim's suggestions on bitfields.
- Placed cfi_state at the end of thread_info block so that current situation
is not disturbed with respect to member fields of thread_info in single
cacheline.
v13:
- cpu_supports_shadow_stack/cpu_supports_indirect_br_lp_instr uses
riscv_has_extension_unlikely()
- uses nops(count) to create nop slide
- RISCV_ACQUIRE_BARRIER is not needed in `amo_user_shstk`. Removed it
- changed ternaries to simply use implicit casting to convert to bool.
- kernel command line allows to disable zicfilp and zicfiss independently.
updated kernel-parameters.txt.
- ptrace user abi for cfi uses bitmasks instead of bitfields. Added ptrace
kselftest.
- cosmetic and grammatical changes to documentation.
v12:
- It seems like I had accidently squashed arch agnostic indirect branch
tracking prctl and riscv implementation of those prctls. Split them again.
- set_shstk_status/set_indir_lp_status perform CSR writes only when CPU
support is available. As suggested by Zong Li.
- Some minor clean up in kselftests as suggested by Zong Li.
v11:
- patch "arch/riscv: compile vdso with landing pad" was unconditionally
selecting `_zicfilp` for vDSO compile. fixed that. Changed `lpad 1` to
to `lpad 0`.
v10:
- dropped "mm: helper `is_shadow_stack_vma` to check shadow stack vma". This patch
is not that interesting to this patch series for risc-v. There are instances in
arch directories where VM_SHADOW_STACK flag is anyways used. Dropping this patch
to expedite merging in riscv tree.
- Took suggestions from `Clement` on "riscv: zicfiss / zicfilp enumeration" to
validate presence of cfi based on config.
- Added a patch for vDSO to have `lpad 0`. I had omitted this earlier to make sure
we add single vdso object with cfi enabled. But a vdso object with scheme of
zero labeled landing pad is least common denominator and should work with all
objects of zero labeled as well as function-signature labeled objects.
v9:
- rebased on master (39a803b754d5 fix braino in "9p: fix ->rename_sem exclusion")
- dropped "mm: Introduce ARCH_HAS_USER_SHADOW_STACK" (master has it from arm64/gcs)
- dropped "prctl: arch-agnostic prctl for shadow stack" (master has it from arm64/gcs)
v8:
- rebased on palmer/for-next
- dropped samuel holland's `envcfg` context switch patches.
they are in parlmer/for-next
v7:
- Removed "riscv/Kconfig: enable HAVE_EXIT_THREAD for riscv"
Instead using `deactivate_mm` flow to clean up.
see here for more context
https://lore.kernel.org/all/20230908203655.543765-1-rick.p.edgecombe@intel.…
- Changed the header include in `kselftest`. Hopefully this fixes compile
issue faced by Zong Li at SiFive.
- Cleaned up an orphaned change to `mm/mmap.c` in below patch
"riscv/mm : ensure PROT_WRITE leads to VM_READ | VM_WRITE"
- Lock interfaces for shadow stack and indirect branch tracking expect arg == 0
Any future evolution of this interface should accordingly define how arg should
be setup.
- `mm/map.c` has an instance of using `VM_SHADOW_STACK`. Fixed it to use helper
`is_shadow_stack_vma`.
- Link to v6: https://lore.kernel.org/r/20241008-v5_user_cfi_series-v6-0-60d9fe073f37@riv…
v6:
- Picked up Samuel Holland's changes as is with `envcfg` placed in
`thread` instead of `thread_info`
- fixed unaligned newline escapes in kselftest
- cleaned up messages in kselftest and included test output in commit message
- fixed a bug in clone path reported by Zong Li
- fixed a build issue if CONFIG_RISCV_ISA_V is not selected
(this was introduced due to re-factoring signal context
management code)
v5:
- rebased on v6.12-rc1
- Fixed schema related issues in device tree file
- Fixed some of the documentation related issues in zicfilp/ss.rst
(style issues and added index)
- added `SHADOW_STACK_SET_MARKER` so that implementation can define base
of shadow stack.
- Fixed warnings on definitions added in usercfi.h when
CONFIG_RISCV_USER_CFI is not selected.
- Adopted context header based signal handling as proposed by Andy Chiu
- Added support for enabling kernel mode access to shadow stack using
FWFT
(https://github.com/riscv-non-isa/riscv-sbi-doc/blob/master/src/ext-firmware…)
- Link to v5: https://lore.kernel.org/r/20241001-v5_user_cfi_series-v1-0-3ba65b6e550f@riv…
(Note: I had an issue in my workflow due to which version number wasn't
picked up correctly while sending out patches)
v4:
- rebased on 6.11-rc6
- envcfg: Converged with Samuel Holland's patches for envcfg management on per-
thread basis.
- vma_is_shadow_stack is renamed to is_vma_shadow_stack
- picked up Mark Brown's `ARCH_HAS_USER_SHADOW_STACK` patch
- signal context: using extended context management to maintain compatibility.
- fixed `-Wmissing-prototypes` compiler warnings for prctl functions
- Documentation fixes and amending typos.
- Link to v4: https://lore.kernel.org/all/20240912231650.3740732-1-debug@rivosinc.com/
v3:
- envcfg
logic to pick up base envcfg had a bug where `ENVCFG_CBZE` could have been
picked on per task basis, even though CPU didn't implement it. Fixed in
this series.
- dt-bindings
As suggested, split into separate commit. fixed the messaging that spec is
in public review
- arch_is_shadow_stack change
arch_is_shadow_stack changed to vma_is_shadow_stack
- hwprobe
zicfiss / zicfilp if present will get enumerated in hwprobe
- selftests
As suggested, added object and binary filenames to .gitignore
Selftest binary anyways need to be compiled with cfi enabled compiler which
will make sure that landing pad and shadow stack are enabled. Thus removed
separate enable/disable tests. Cleaned up tests a bit.
- Link to v3: https://lore.kernel.org/lkml/20240403234054.2020347-1-debug@rivosinc.com/
v2:
- Using config `CONFIG_RISCV_USER_CFI`, kernel support for riscv control flow
integrity for user mode programs can be compiled in the kernel.
- Enabling of control flow integrity for user programs is left to user runtime
- This patch series introduces arch agnostic `prctls` to enable shadow stack
and indirect branch tracking. And implements them on riscv.
---
Changes in v21:
- Link to v20: https://lore.kernel.org/r/20251013-v5_user_cfi_series-v20-0-b9de4be9912e@ri…
Changes in v20:
- Link to v19: https://lore.kernel.org/r/20250731-v5_user_cfi_series-v19-0-09b468d7beab@ri…
Changes in v19:
- Link to v18: https://lore.kernel.org/r/20250711-v5_user_cfi_series-v18-0-a8ee62f9f38e@ri…
Changes in v18:
- Link to v17: https://lore.kernel.org/r/20250604-v5_user_cfi_series-v17-0-4565c2cf869f@ri…
Changes in v17:
- Link to v16: https://lore.kernel.org/r/20250522-v5_user_cfi_series-v16-0-64f61a35eee7@ri…
Changes in v16:
- Link to v15: https://lore.kernel.org/r/20250502-v5_user_cfi_series-v15-0-914966471885@ri…
Changes in v15:
- changelog posted just below cover letter
- Link to v14: https://lore.kernel.org/r/20250429-v5_user_cfi_series-v14-0-5239410d012a@ri…
Changes in v14:
- changelog posted just below cover letter
- Link to v13: https://lore.kernel.org/r/20250424-v5_user_cfi_series-v13-0-971437de586a@ri…
Changes in v13:
- changelog posted just below cover letter
- Link to v12: https://lore.kernel.org/r/20250314-v5_user_cfi_series-v12-0-e51202b53138@ri…
Changes in v12:
- changelog posted just below cover letter
- Link to v11: https://lore.kernel.org/r/20250310-v5_user_cfi_series-v11-0-86b36cbfb910@ri…
Changes in v11:
- changelog posted just below cover letter
- Link to v10: https://lore.kernel.org/r/20250210-v5_user_cfi_series-v10-0-163dcfa31c60@ri…
---
Andy Chiu (1):
riscv: signal: abstract header saving for setup_sigcontext
Deepak Gupta (26):
mm: VM_SHADOW_STACK definition for riscv
dt-bindings: riscv: zicfilp and zicfiss in dt-bindings (extensions.yaml)
riscv: zicfiss / zicfilp enumeration
riscv: zicfiss / zicfilp extension csr and bit definitions
riscv: usercfi state for task and save/restore of CSR_SSP on trap entry/exit
riscv/mm : ensure PROT_WRITE leads to VM_READ | VM_WRITE
riscv/mm: manufacture shadow stack pte
riscv/mm: teach pte_mkwrite to manufacture shadow stack PTEs
riscv/mm: write protect and shadow stack
riscv/mm: Implement map_shadow_stack() syscall
riscv/shstk: If needed allocate a new shadow stack on clone
riscv: Implements arch agnostic shadow stack prctls
prctl: arch-agnostic prctl for indirect branch tracking
riscv: Implements arch agnostic indirect branch tracking prctls
riscv/traps: Introduce software check exception and uprobe handling
riscv/signal: save and restore of shadow stack for signal
riscv/kernel: update __show_regs to print shadow stack register
riscv/ptrace: riscv cfi status and state via ptrace and in core files
riscv/hwprobe: zicfilp / zicfiss enumeration in hwprobe
riscv: kernel command line option to opt out of user cfi
riscv: enable kernel access to shadow stack memory via FWFT sbi call
arch/riscv: dual vdso creation logic and select vdso based on hw
riscv: create a config for shadow stack and landing pad instr support
riscv: Documentation for landing pad / indirect branch tracking
riscv: Documentation for shadow stack on riscv
kselftest/riscv: kselftest for user mode cfi
Jim Shu (1):
arch/riscv: compile vdso with landing pad and shadow stack note
Documentation/admin-guide/kernel-parameters.txt | 8 +
Documentation/arch/riscv/index.rst | 2 +
Documentation/arch/riscv/zicfilp.rst | 115 +++++
Documentation/arch/riscv/zicfiss.rst | 179 +++++++
.../devicetree/bindings/riscv/extensions.yaml | 14 +
arch/riscv/Kconfig | 21 +
arch/riscv/Makefile | 8 +-
arch/riscv/configs/hardening.config | 4 +
arch/riscv/include/asm/asm-prototypes.h | 1 +
arch/riscv/include/asm/assembler.h | 44 ++
arch/riscv/include/asm/cpufeature.h | 12 +
arch/riscv/include/asm/csr.h | 16 +
arch/riscv/include/asm/entry-common.h | 2 +
arch/riscv/include/asm/hwcap.h | 2 +
arch/riscv/include/asm/mman.h | 26 +
arch/riscv/include/asm/mmu_context.h | 7 +
arch/riscv/include/asm/pgtable.h | 30 +-
arch/riscv/include/asm/processor.h | 1 +
arch/riscv/include/asm/thread_info.h | 3 +
arch/riscv/include/asm/usercfi.h | 95 ++++
arch/riscv/include/asm/vdso.h | 13 +-
arch/riscv/include/asm/vector.h | 3 +
arch/riscv/include/uapi/asm/hwprobe.h | 2 +
arch/riscv/include/uapi/asm/ptrace.h | 34 ++
arch/riscv/include/uapi/asm/sigcontext.h | 1 +
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/asm-offsets.c | 10 +
arch/riscv/kernel/cpufeature.c | 27 +
arch/riscv/kernel/entry.S | 38 ++
arch/riscv/kernel/head.S | 27 +
arch/riscv/kernel/process.c | 27 +-
arch/riscv/kernel/ptrace.c | 95 ++++
arch/riscv/kernel/signal.c | 148 +++++-
arch/riscv/kernel/sys_hwprobe.c | 2 +
arch/riscv/kernel/sys_riscv.c | 10 +
arch/riscv/kernel/traps.c | 54 ++
arch/riscv/kernel/usercfi.c | 545 +++++++++++++++++++++
arch/riscv/kernel/vdso.c | 7 +
arch/riscv/kernel/vdso/Makefile | 40 +-
arch/riscv/kernel/vdso/flush_icache.S | 4 +
arch/riscv/kernel/vdso/gen_vdso_offsets.sh | 4 +-
arch/riscv/kernel/vdso/getcpu.S | 4 +
arch/riscv/kernel/vdso/note.S | 3 +
arch/riscv/kernel/vdso/rt_sigreturn.S | 4 +
arch/riscv/kernel/vdso/sys_hwprobe.S | 4 +
arch/riscv/kernel/vdso/vgetrandom-chacha.S | 5 +-
arch/riscv/kernel/vdso_cfi/Makefile | 25 +
arch/riscv/kernel/vdso_cfi/vdso-cfi.S | 11 +
arch/riscv/mm/init.c | 2 +-
arch/riscv/mm/pgtable.c | 16 +
include/linux/cpu.h | 4 +
include/linux/mm.h | 7 +
include/uapi/linux/elf.h | 2 +
include/uapi/linux/prctl.h | 27 +
kernel/sys.c | 30 ++
tools/testing/selftests/riscv/Makefile | 2 +-
tools/testing/selftests/riscv/cfi/.gitignore | 3 +
tools/testing/selftests/riscv/cfi/Makefile | 16 +
tools/testing/selftests/riscv/cfi/cfi_rv_test.h | 82 ++++
tools/testing/selftests/riscv/cfi/riscv_cfi_test.c | 173 +++++++
tools/testing/selftests/riscv/cfi/shadowstack.c | 385 +++++++++++++++
tools/testing/selftests/riscv/cfi/shadowstack.h | 27 +
62 files changed, 2474 insertions(+), 41 deletions(-)
---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20240930-v5_user_cfi_series-3dc332f8f5b2
--
- debug