Hi,
here comes the v9 of the HID-BPF series.
Again, for a full explanation of HID-BPF, please refer to the last patch
in this series (23/23).
This version sees some minor improvements compared to v7 and v8, only
focusing on the reviews I got. (v8 was a single patch update)
- patch 1/24 in v7 was dropped as it is already fixed upstream
- patch 1/23 in v9 is now capable of handling all functions, not just
kfuncs (tested with the selftests only)
- some minor nits from Greg's review
- a rebase on top of the current bpf-next tree as the kfunc definition
changed (for the better).
Cheers,
Benjamin
Benjamin Tissoires (23):
bpf/verifier: allow all functions to read user provided context
bpf/verifier: do not clear meta in check_mem_size
selftests/bpf: add test for accessing ctx from syscall program type
bpf/verifier: allow kfunc to return an allocated mem
selftests/bpf: Add tests for kfunc returning a memory pointer
bpf: prepare for more bpf syscall to be used from kernel and user
space.
libbpf: add map_get_fd_by_id and map_delete_elem in light skeleton
HID: core: store the unique system identifier in hid_device
HID: export hid_report_type to uapi
HID: convert defines of HID class requests into a proper enum
HID: Kconfig: split HID support and hid-core compilation
HID: initial BPF implementation
selftests/bpf: add tests for the HID-bpf initial implementation
HID: bpf: allocate data memory for device_event BPF programs
selftests/bpf/hid: add test to change the report size
HID: bpf: introduce hid_hw_request()
selftests/bpf: add tests for bpf_hid_hw_request
HID: bpf: allow to change the report descriptor
selftests/bpf: add report descriptor fixup tests
selftests/bpf: Add a test for BPF_F_INSERT_HEAD
samples/bpf: HID: add new hid_mouse example
samples/bpf: HID: add Surface Dial example
Documentation: add HID-BPF docs
Documentation/hid/hid-bpf.rst | 512 +++++++++
Documentation/hid/index.rst | 1 +
drivers/Makefile | 2 +-
drivers/hid/Kconfig | 20 +-
drivers/hid/Makefile | 2 +
drivers/hid/bpf/Kconfig | 17 +
drivers/hid/bpf/Makefile | 11 +
drivers/hid/bpf/entrypoints/Makefile | 93 ++
drivers/hid/bpf/entrypoints/README | 4 +
drivers/hid/bpf/entrypoints/entrypoints.bpf.c | 66 ++
.../hid/bpf/entrypoints/entrypoints.lskel.h | 682 ++++++++++++
drivers/hid/bpf/hid_bpf_dispatch.c | 526 ++++++++++
drivers/hid/bpf/hid_bpf_dispatch.h | 28 +
drivers/hid/bpf/hid_bpf_jmp_table.c | 577 ++++++++++
drivers/hid/hid-core.c | 49 +-
include/linux/bpf.h | 9 +-
include/linux/btf.h | 10 +
include/linux/hid.h | 38 +-
include/linux/hid_bpf.h | 148 +++
include/uapi/linux/hid.h | 26 +-
include/uapi/linux/hid_bpf.h | 25 +
kernel/bpf/btf.c | 109 +-
kernel/bpf/syscall.c | 10 +-
kernel/bpf/verifier.c | 64 +-
net/bpf/test_run.c | 21 +
samples/bpf/.gitignore | 2 +
samples/bpf/Makefile | 27 +
samples/bpf/hid_mouse.bpf.c | 134 +++
samples/bpf/hid_mouse.c | 161 +++
samples/bpf/hid_surface_dial.bpf.c | 161 +++
samples/bpf/hid_surface_dial.c | 232 ++++
tools/include/uapi/linux/hid.h | 62 ++
tools/include/uapi/linux/hid_bpf.h | 25 +
tools/lib/bpf/skel_internal.h | 23 +
tools/testing/selftests/bpf/Makefile | 5 +-
tools/testing/selftests/bpf/config | 3 +
tools/testing/selftests/bpf/prog_tests/hid.c | 990 ++++++++++++++++++
.../selftests/bpf/prog_tests/kfunc_call.c | 76 ++
tools/testing/selftests/bpf/progs/hid.c | 206 ++++
.../selftests/bpf/progs/kfunc_call_test.c | 125 +++
40 files changed, 5198 insertions(+), 84 deletions(-)
create mode 100644 Documentation/hid/hid-bpf.rst
create mode 100644 drivers/hid/bpf/Kconfig
create mode 100644 drivers/hid/bpf/Makefile
create mode 100644 drivers/hid/bpf/entrypoints/Makefile
create mode 100644 drivers/hid/bpf/entrypoints/README
create mode 100644 drivers/hid/bpf/entrypoints/entrypoints.bpf.c
create mode 100644 drivers/hid/bpf/entrypoints/entrypoints.lskel.h
create mode 100644 drivers/hid/bpf/hid_bpf_dispatch.c
create mode 100644 drivers/hid/bpf/hid_bpf_dispatch.h
create mode 100644 drivers/hid/bpf/hid_bpf_jmp_table.c
create mode 100644 include/linux/hid_bpf.h
create mode 100644 include/uapi/linux/hid_bpf.h
create mode 100644 samples/bpf/hid_mouse.bpf.c
create mode 100644 samples/bpf/hid_mouse.c
create mode 100644 samples/bpf/hid_surface_dial.bpf.c
create mode 100644 samples/bpf/hid_surface_dial.c
create mode 100644 tools/include/uapi/linux/hid.h
create mode 100644 tools/include/uapi/linux/hid_bpf.h
create mode 100644 tools/testing/selftests/bpf/prog_tests/hid.c
create mode 100644 tools/testing/selftests/bpf/progs/hid.c
--
2.36.1
From: Roberto Sassu <roberto.sassu(a)huawei.com>
One of the desirable features in security is the ability to restrict import
of data to a given system based on data authenticity. If data import can be
restricted, it would be possible to enforce a system-wide policy based on
the signing keys the system owner trusts.
This feature is widely used in the kernel. For example, if the restriction
is enabled, kernel modules can be plugged in only if they are signed with a
key whose public part is in the primary or secondary keyring.
For eBPF, it can be useful as well. For example, it might be useful to
authenticate data an eBPF program makes security decisions on.
After a discussion in the eBPF mailing list, it was decided that the stated
goal should be accomplished by introducing four new kfuncs:
bpf_lookup_user_key() and bpf_lookup_system_key(), for retrieving a keyring
with keys trusted for signature verification, respectively from its serial
and from a pre-determined ID; bpf_key_put(), to release the reference
obtained with the former two kfuncs, bpf_verify_pkcs7_signature(), for
verifying PKCS#7 signatures.
Other than the key serial, bpf_lookup_user_key() also accepts key lookup
flags, that influence the behavior of the lookup. bpf_lookup_system_key()
accepts pre-determined IDs defined in include/linux/verification.h.
bpf_key_put() accepts the new bpf_key structure, introduced to tell whether
the other structure member, a key pointer, is valid or not. The reason is
that verify_pkcs7_signature() also accepts invalid pointers, set with the
pre-determined ID, to select a system-defined keyring. key_put() must be
called only for valid key pointers.
Since the two key lookup functions allocate memory and one increments a key
reference count, they must be used in conjunction with bpf_key_put(). The
latter must be called only if the lookup functions returned a non-NULL
pointer. The verifier denies the execution of eBPF programs that don't
respect this rule.
The two key lookup functions should be used in alternative, depending on
the use case. While bpf_lookup_user_key() provides great flexibility, it
seems suboptimal in terms of security guarantees, as even if the eBPF
program is assumed to be trusted, the serial used to obtain the key pointer
might come from untrusted user space not choosing one that the system
administrator approves to enforce a mandatory policy.
bpf_lookup_system_key() instead provides much stronger guarantees,
especially if the pre-determined ID is not passed by user space but is
hardcoded in the eBPF program, and that program is signed. In this case,
bpf_verify_pkcs7_signature() will always perform signature verification
with a key that the system administrator approves, i.e. the primary,
secondary or platform keyring.
Nevertheless, key permission checks need to be done accurately. Since
bpf_lookup_user_key() cannot determine how a key will be used by other
kfuncs, it has to defer the permission check to the actual kfunc using the
key. It does it by calling lookup_user_key() with KEY_DEFER_PERM_CHECK as
needed permission. Later, bpf_verify_pkcs7_signature(), if called,
completes the permission check by calling key_validate(). It does not need
to call key_task_permission() with permission KEY_NEED_SEARCH, as it is
already done elsewhere by the key subsystem. Future kfuncs using the
bpf_key structure need to implement the proper checks as well.
Finally, the last kfunc, bpf_verify_pkcs7_signature(), accepts the data and
signature to verify as eBPF dynamic pointers, to minimize the number of
kfunc parameters, and the keyring with keys for signature verification as a
bpf_key structure, returned by one of the two key lookup functions.
bpf_lookup_user_key() and bpf_verify_pkcs7_signature() can be called only
from sleepable programs, because of memory allocation and crypto
operations. For example, the lsm.s/bpf attach point is suitable,
fexit/array_map_update_elem is not.
The correctness of implementation of the new kfuncs and of their usage is
checked with the introduced tests.
The patch set includes a patch from another author (dependency) for sake of
completeness. It is organized as follows.
Patch 1 from KP Singh allows kfuncs to be used by LSM programs. Patch 2
splits is_dynptr_reg_valid_init() and introduces is_dynptr_type_expected(),
to know more precisely the cause of a negative result of a dynamic pointer
check. Patch 3 allows dynamic pointers to be used as kfunc parameters.
Patch 4 exports bpf_dynptr_get_size(), to obtain the real size of data
carried by a dynamic pointer. Patch 5 makes available for new eBPF kfuncs
some key-related definitions. Patch 6 introduces the bpf_lookup_*_key() and
bpf_key_put() kfuncs. Patch 7 introduces the bpf_verify_pkcs7_signature()
kfunc. Patch 8 changes the testing kernel configuration to compile
everything as built-in. Finally, patches 9-12 introduce the tests.
Changelog
v13:
- Split is_dynptr_reg_valid_init() and introduce is_dynptr_type_expected()
to see if the dynamic pointer type passed as argument to a kfunc is
supported (suggested by Kumar)
- Add forward declaration of struct key in include/linux/bpf.h (suggested
by Song)
- Declare mask for key lookup flags, remove key_lookup_flags_check()
(suggested by Jarkko and KP)
- Allow only certain dynamic pointer types (currently, local) to be passed
as argument to kfuncs (suggested by Kumar)
- For each dynamic pointer parameter in kfunc, additionally check if the
passed pointer is to the stack (suggested by Kumar)
- Split the validity/initialization and dynamic pointer type check also in
the verifier, and adjust the expected error message in the test (a test
for an unexpected dynptr type passed to a helper cannot be added due to
missing suitable helpers, but this case has been tested manually)
- Add verifier tests to check the dynamic pointers passed as argument to
kfuncs (suggested by Kumar)
v12:
- Put lookup_key and verify_pkcs7_sig tests in deny list for s390x (JIT
does not support calling kernel function)
v11:
- Move stringify_struct() macro to include/linux/btf.h (suggested by
Daniel)
- Change kernel configuration options in
tools/testing/selftests/bpf/config* from =m to =y
v10:
- Introduce key_lookup_flags_check() and system_keyring_id_check() inline
functions to check parameters (suggested by KP)
- Fix descriptions and comment of key-related kfuncs (suggested by KP)
- Register kfunc set only once (suggested by Alexei)
- Move needed kernel options to the architecture-independent configuration
for testing
v9:
- Drop patch to introduce KF_SLEEPABLE kfunc flag (already merged)
- Rename valid_ptr member of bpf_key to has_ref (suggested by Daniel)
- Check dynamic pointers in kfunc definition with bpf_dynptr_kern struct
definition instead of string, to detect structure renames (suggested by
Daniel)
- Explicitly say that we permit initialized dynamic pointers in kfunc
definition (suggested by Daniel)
- Remove noinline __weak from kfuncs definition (reported by Daniel)
- Simplify key lookup flags check in bpf_lookup_user_key() (suggested by
Daniel)
- Explain the reason for deferring key permission check (suggested by
Daniel)
- Allocate memory with GFP_ATOMIC in bpf_lookup_system_key(), and remove
KF_SLEEPABLE kfunc flag from kfunc declaration (suggested by Daniel)
- Define only one kfunc set and remove the loop for registration
(suggested by Alexei)
v8:
- Define the new bpf_key structure to carry the key pointer and whether
that pointer is valid or not (suggested by Daniel)
- Drop patch to mark a kfunc parameter with the __maybe_null suffix
- Improve documentation of kfuncs
- Introduce bpf_lookup_system_key() to obtain a key pointer suitable for
verify_pkcs7_signature() (suggested by Daniel)
- Use the new kfunc registration API
- Drop patch to test the __maybe_null suffix
- Add tests for bpf_lookup_system_key()
v7:
- Add support for using dynamic and NULL pointers in kfunc (suggested by
Alexei)
- Add new kfunc-related tests
v6:
- Switch back to key lookup helpers + signature verification (until v5),
and defer permission check from bpf_lookup_user_key() to
bpf_verify_pkcs7_signature()
- Add additional key lookup test to illustrate the usage of the
KEY_LOOKUP_CREATE flag and validate the flags (suggested by Daniel)
- Make description of flags of bpf_lookup_user_key() more user-friendly
(suggested by Daniel)
- Fix validation of flags parameter in bpf_lookup_user_key() (reported by
Daniel)
- Rename bpf_verify_pkcs7_signature() keyring-related parameters to
user_keyring and system_keyring to make their purpose more clear
- Accept keyring-related parameters of bpf_verify_pkcs7_signature() as
alternatives (suggested by KP)
- Replace unsigned long type with u64 in helper declaration (suggested by
Daniel)
- Extend the bpf_verify_pkcs7_signature() test by calling the helper
without data, by ensuring that the helper enforces the keyring-related
parameters as alternatives, by ensuring that the helper rejects
inaccessible and expired keyrings, and by checking all system keyrings
- Move bpf_lookup_user_key() and bpf_key_put() usage tests to
ref_tracking.c (suggested by John)
- Call bpf_lookup_user_key() and bpf_key_put() only in sleepable programs
v5:
- Move KEY_LOOKUP_ to include/linux/key.h
for validation of bpf_verify_pkcs7_signature() parameter
- Remove bpf_lookup_user_key() and bpf_key_put() helpers, and the
corresponding tests
- Replace struct key parameter of bpf_verify_pkcs7_signature() with the
keyring serial and lookup flags
- Call lookup_user_key() and key_put() in bpf_verify_pkcs7_signature()
code, to ensure that the retrieved key is used according to the
permission requested at lookup time
- Clarified keyring precedence in the description of
bpf_verify_pkcs7_signature() (suggested by John)
- Remove newline in the second argument of ASSERT_
- Fix helper prototype regular expression in bpf_doc.py
v4:
- Remove bpf_request_key_by_id(), don't return an invalid pointer that
other helpers can use
- Pass the keyring ID (without ULONG_MAX, suggested by Alexei) to
bpf_verify_pkcs7_signature()
- Introduce bpf_lookup_user_key() and bpf_key_put() helpers (suggested by
Alexei)
- Add lookup_key_norelease test, to ensure that the verifier blocks eBPF
programs which don't decrement the key reference count
- Parse raw PKCS#7 signature instead of module-style signature in the
verify_pkcs7_signature test (suggested by Alexei)
- Parse kernel module in user space and pass raw PKCS#7 signature to the
eBPF program for signature verification
v3:
- Rename bpf_verify_signature() back to bpf_verify_pkcs7_signature() to
avoid managing different parameters for each signature verification
function in one helper (suggested by Daniel)
- Use dynamic pointers and export bpf_dynptr_get_size() (suggested by
Alexei)
- Introduce bpf_request_key_by_id() to give more flexibility to the caller
of bpf_verify_pkcs7_signature() to retrieve the appropriate keyring
(suggested by Alexei)
- Fix test by reordering the gcc command line, always compile sign-file
- Improve helper support check mechanism in the test
v2:
- Rename bpf_verify_pkcs7_signature() to a more generic
bpf_verify_signature() and pass the signature type (suggested by KP)
- Move the helper and prototype declaration under #ifdef so that user
space can probe for support for the helper (suggested by Daniel)
- Describe better the keyring types (suggested by Daniel)
- Include linux/bpf.h instead of vmlinux.h to avoid implicit or
redeclaration
- Make the test selfcontained (suggested by Alexei)
v1:
- Don't define new map flag but introduce simple wrapper of
verify_pkcs7_signature() (suggested by Alexei and KP)
KP Singh (1):
bpf: Allow kfuncs to be used in LSM programs
Roberto Sassu (11):
bpf: Move dynptr type check to is_dynptr_type_expected()
btf: Allow dynamic pointer parameters in kfuncs
bpf: Export bpf_dynptr_get_size()
KEYS: Move KEY_LOOKUP_ to include/linux/key.h and set
KEY_LOOKUP_FLAGS_ALL
bpf: Add bpf_lookup_*_key() and bpf_key_put() kfuncs
bpf: Add bpf_verify_pkcs7_signature() kfunc
selftests/bpf: Compile kernel with everything as built-in
selftests/bpf: Add verifier tests for bpf_lookup_*_key() and
bpf_key_put()
selftests/bpf: Add additional tests for bpf_lookup_*_key()
selftests/bpf: Add test for bpf_verify_pkcs7_signature() kfunc
selftests/bpf: Add verifier tests for dynamic pointers parameters in
kfuncs
include/linux/bpf.h | 9 +
include/linux/bpf_verifier.h | 5 +
include/linux/btf.h | 9 +
include/linux/key.h | 4 +
include/linux/verification.h | 8 +
kernel/bpf/btf.c | 34 ++
kernel/bpf/helpers.c | 2 +-
kernel/bpf/verifier.c | 35 +-
kernel/trace/bpf_trace.c | 180 ++++++++
security/keys/internal.h | 2 -
tools/testing/selftests/bpf/DENYLIST.s390x | 2 +
tools/testing/selftests/bpf/Makefile | 14 +-
tools/testing/selftests/bpf/config | 32 +-
tools/testing/selftests/bpf/config.x86_64 | 7 +-
.../testing/selftests/bpf/prog_tests/dynptr.c | 2 +-
.../selftests/bpf/prog_tests/lookup_key.c | 112 +++++
.../bpf/prog_tests/verify_pkcs7_sig.c | 399 ++++++++++++++++++
.../selftests/bpf/progs/test_lookup_key.c | 46 ++
.../bpf/progs/test_verify_pkcs7_sig.c | 100 +++++
tools/testing/selftests/bpf/test_verifier.c | 3 +-
.../bpf/verifier/kfunc_dynptr_param.c | 72 ++++
.../selftests/bpf/verifier/ref_tracking.c | 139 ++++++
.../testing/selftests/bpf/verify_sig_setup.sh | 104 +++++
23 files changed, 1285 insertions(+), 35 deletions(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/lookup_key.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/verify_pkcs7_sig.c
create mode 100644 tools/testing/selftests/bpf/progs/test_lookup_key.c
create mode 100644 tools/testing/selftests/bpf/progs/test_verify_pkcs7_sig.c
create mode 100644 tools/testing/selftests/bpf/verifier/kfunc_dynptr_param.c
create mode 100755 tools/testing/selftests/bpf/verify_sig_setup.sh
--
2.25.1
This series enables the ring-based dirty memory tracking for ARM64.
The feature has been available and enabled on x86 for a while. It
is beneficial when the number of dirty pages is small in a checkpointing
system or live migration scenario. More details can be found from
fb04a1eddb1a ("KVM: X86: Implement ring-based dirty memory tracking").
The generic part has been comprehensive enough, meaning there isn't too
much work, needed to extend it to ARM64.
- PATCH[1] enables the feature on ARM64
- PATCH[2-5] improves kvm/selftests/dirty_log_test
Testing
=======
- kvm/selftests/dirty_log_test
- Live migration by QEMU
- Host with 4KB or 64KB base page size
Gavin Shan (5):
KVM: arm64: Enable ring-based dirty memory tracking
KVM: selftests: Use host page size to map ring buffer in
dirty_log_test
KVM: selftests: Dirty host pages in dirty_log_test
KVM: selftests: Clear dirty ring states between two modes in
dirty_log_test
KVM: selftests: Automate choosing dirty ring size in dirty_log_test
Documentation/virt/kvm/api.rst | 2 +-
arch/arm64/include/uapi/asm/kvm.h | 1 +
arch/arm64/kvm/Kconfig | 1 +
arch/arm64/kvm/arm.c | 8 ++
tools/testing/selftests/kvm/dirty_log_test.c | 101 ++++++++++++++-----
tools/testing/selftests/kvm/lib/kvm_util.c | 2 +-
6 files changed, 88 insertions(+), 27 deletions(-)
--
2.23.0
Commit c272612cb4a2 ("kunit: Taint the kernel when KUnit tests are run")
added a new taint flag for when in-kernel tests run. This commit adds
recognition of this new flag in kernel-chktaint.
Reviewed-by: David Gow <davidgow(a)google.com>
Signed-off-by: Joe Fradley <joefradley(a)google.com>
---
Changes in v2:
- based off of kselftest/kunit branch
- Added David's Reviewed-by tag
tools/debugging/kernel-chktaint | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/tools/debugging/kernel-chktaint b/tools/debugging/kernel-chktaint
index f1af27ce9f20..279be06332be 100755
--- a/tools/debugging/kernel-chktaint
+++ b/tools/debugging/kernel-chktaint
@@ -187,6 +187,7 @@ else
echo " * auxiliary taint, defined for and used by distros (#16)"
fi
+
T=`expr $T / 2`
if [ `expr $T % 2` -eq 0 ]; then
addout " "
@@ -195,6 +196,14 @@ else
echo " * kernel was built with the struct randomization plugin (#17)"
fi
+T=`expr $T / 2`
+if [ `expr $T % 2` -eq 0 ]; then
+ addout " "
+else
+ addout "N"
+ echo " * an in-kernel test (such as a KUnit test) has been run (#18)"
+fi
+
echo "For a more detailed explanation of the various taint flags see"
echo " Documentation/admin-guide/tainted-kernels.rst in the Linux kernel sources"
echo " or https://kernel.org/doc/html/latest/admin-guide/tainted-kernels.html"
--
2.37.1.595.g718a3a8f04-goog