If we try to access argument which is pointer to const void, it's an
UNKNOWN type, verifier will fail to load.
Use is_void_or_int_ptr to check if type is void or int pointer.
Add a selftest to check it.
---
KaFai Wan (2):
bpf: Allow access to const void pointer arguments in tracing programs
selftests/bpf: Add test to access const void pointer argument in
tracing program
kernel/bpf/btf.c | 13 +++----------
net/bpf/test_run.c | 8 +++++++-
.../selftests/bpf/progs/verifier_btf_ctx_access.c | 12 ++++++++++++
3 files changed, 22 insertions(+), 11 deletions(-)
Changelog:
v2->v3: Addressed comments from jirka
- remove duplicate checks for void pointer
Details in here:
https://lore.kernel.org/bpf/20250416161756.1079178-1-kafai.wan@hotmail.com/
v1->v2: Addressed comments from jirka
- use btf_type_is_void to check if type is void
- merge is_void_ptr and is_int_ptr to is_void_or_int_ptr
- fix selftests
Details in here:
https://lore.kernel.org/all/20250412170626.3638516-1-kafai.wan@hotmail.com/
--
2.43.0
When the select of PRIME_MUMBERS was removed from it's KUnit test
Kconfig nothing was added to the KUnit configs, meaning that when run
via the KUnit runner the tests are neither built nor run. Add
PRIME_NUMBERS to all_tests.config so they are enabled when the KUnit
runner builds the kernel.
Fixes: 3f2925174f8b ("lib/prime_numbers: KUnit test should not select PRIME_NUMBERS")
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
tools/testing/kunit/configs/all_tests.config | 2 ++
1 file changed, 2 insertions(+)
diff --git a/tools/testing/kunit/configs/all_tests.config b/tools/testing/kunit/configs/all_tests.config
index cdd9782f9646..7bb885b0c32d 100644
--- a/tools/testing/kunit/configs/all_tests.config
+++ b/tools/testing/kunit/configs/all_tests.config
@@ -43,6 +43,8 @@ CONFIG_REGMAP_BUILD=y
CONFIG_AUDIT=y
+CONFIG_PRIME_NUMBERS=y
+
CONFIG_SECURITY=y
CONFIG_SECURITY_APPARMOR=y
CONFIG_SECURITY_LANDLOCK=y
---
base-commit: 9c32cda43eb78f78c73aee4aa344b777714e259b
change-id: 20250422-lib-fix-prime-numbers-kunit-323659c2cfe2
Best regards,
--
Mark Brown <broonie(a)kernel.org>
From: Steven Rostedt <rostedt(a)goodmis.org>
Running the following commands was broken:
# cd /sys/kernel/tracing
# echo "filename.ustring ~ \"/proc*\"" > events/syscalls/sys_enter_openat/filter
# echo 1 > events/syscalls/sys_enter_openat/enable
# ls /proc/$$/maps
# cat trace
And would produce nothing when it should have produced something like:
ls-1192 [007] ..... 8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)
Add a test to check this case so that it will be caught if it breaks
again.
Link: https://lore.kernel.org/linux-trace-kernel/20250417183003.505835fb@gandalf.…
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
---
Changes since v1: https://lore.kernel.org/20250417223323.3edb4f6c@batman.local.home
- Use $TMPDIR instead of $TESTDIR as test file (Masami Hiramatsu)
.../test.d/filter/event-filter-function.tc | 20 +++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
index 118247b8dd84..c62165fabd0c 100644
--- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
+++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
@@ -80,6 +80,26 @@ if [ $misscnt -gt 0 ]; then
exit_fail
fi
+# Check strings too
+if [ -f events/syscalls/sys_enter_openat/filter ]; then
+ DIRNAME=`basename $TMPDIR`
+ echo "filename.ustring ~ \"*$DIRNAME*\"" > events/syscalls/sys_enter_openat/filter
+ echo 1 > events/syscalls/sys_enter_openat/enable
+ echo 1 > tracing_on
+ ls /bin/sh
+ nocnt=`grep openat trace | wc -l`
+ ls $TMPDIR
+ echo 0 > tracing_on
+ hitcnt=`grep openat trace | wc -l`;
+ echo 0 > events/syscalls/sys_enter_openat/enable
+ if [ $nocnt -gt 0 ]; then
+ exit_fail
+ fi
+ if [ $hitcnt -eq 0 ]; then
+ exit_fail
+ fi
+fi
+
reset_events_filter
exit 0
--
2.47.2
Enabling a (modular) test should not silently enable additional kernel
functionality, as that may increase the attack vector of a product.
Fix this by making PRIME_NUMBERS_KUNIT_TEST depend on PRIME_NUMBERS
instead of selecting it.
After this, one can safely enable CONFIG_KUNIT_ALL_TESTS=m to build
modules for all appropriate tests for ones system, without pulling in
extra unwanted functionality, while still allowing a tester to manually
enable PRIME_NUMBERS and this test suite on a system where PRIME_NUMBERS
is not enabled by default. Resurrect CONFIG_PRIME_NUMBERS=m in
tools/testing/selftests/lib/config for the latter use case.
Fixes: 313b38a6ecb46db4 ("lib/prime_numbers: convert self-test to KUnit")
Signed-off-by: Geert Uytterhoeven <geert(a)linux-m68k.org>
Acked-by: Tamir Duberstein <tamird(a)gmail.com>
---
v2:
- Add Acked-by,
- Resurrect CONFIG_PRIME_NUMBERS=m in
tools/testing/selftests/lib/config.
---
lib/Kconfig.debug | 2 +-
tools/testing/selftests/lib/config | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 4060a89866626c0a..51722f5d041970aa 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -3326,7 +3326,7 @@ config GCD_KUNIT_TEST
config PRIME_NUMBERS_KUNIT_TEST
tristate "Prime number generator test" if !KUNIT_ALL_TESTS
depends on KUNIT
- select PRIME_NUMBERS
+ depends on PRIME_NUMBERS
default KUNIT_ALL_TESTS
help
This option enables the KUnit test suite for the {is,next}_prime_number
diff --git a/tools/testing/selftests/lib/config b/tools/testing/selftests/lib/config
index 81a1f64a22e860a6..377b3699ff312933 100644
--- a/tools/testing/selftests/lib/config
+++ b/tools/testing/selftests/lib/config
@@ -1,2 +1,3 @@
CONFIG_TEST_BITMAP=m
+CONFIG_PRIME_NUMBERS=m
CONFIG_TEST_BITOPS=m
--
2.43.0
This started with a patch that enabled `clippy::ptr_as_ptr`. Benno
Lossin suggested I also look into `clippy::ptr_cast_constness` and I
discovered `clippy::as_ptr_cast_mut`. This series now enables all 3
lints. It also enables `clippy::as_underscore` which ensures other
pointer casts weren't missed.
As a later addition, `clippy::cast_lossless` and `clippy::ref_as_ptr`
are also enabled.
This series depends on "rust: retain pointer mut-ness in
`container_of!`"[1].
Link: https://lore.kernel.org/all/20250409-container-of-mutness-v1-1-64f472b94534… [1]
Signed-off-by: Tamir Duberstein <tamird(a)gmail.com>
---
Changes in v9:
- Replace ref-to-ptr coercion using `let` bindings with
`core::ptr::from_{ref,mut}`. (Boqun Feng).
- Link to v8: https://lore.kernel.org/r/20250409-ptr-as-ptr-v8-0-3738061534ef@gmail.com
Changes in v8:
- Use coercion to go ref -> ptr.
- rustfmt.
- Rebase on v6.15-rc1.
- Extract first commit to its own series as it is shared with other
series.
- Link to v7: https://lore.kernel.org/r/20250325-ptr-as-ptr-v7-0-87ab452147b9@gmail.com
Changes in v7:
- Add patch to enable `clippy::ref_as_ptr`.
- Link to v6: https://lore.kernel.org/r/20250324-ptr-as-ptr-v6-0-49d1b7fd4290@gmail.com
Changes in v6:
- Drop strict provenance patch.
- Fix URLs in doc comments.
- Add patch to enable `clippy::cast_lossless`.
- Rebase on rust-next.
- Link to v5: https://lore.kernel.org/r/20250317-ptr-as-ptr-v5-0-5b5f21fa230a@gmail.com
Changes in v5:
- Use `pointer::addr` in OF. (Boqun Feng)
- Add documentation on stubs. (Benno Lossin)
- Mark stubs `#[inline]`.
- Pick up Alice's RB on a shared commit from
https://lore.kernel.org/all/Z9f-3Aj3_FWBZRrm@google.com/.
- Link to v4: https://lore.kernel.org/r/20250315-ptr-as-ptr-v4-0-b2d72c14dc26@gmail.com
Changes in v4:
- Add missing SoB. (Benno Lossin)
- Use `without_provenance_mut` in alloc. (Boqun Feng)
- Limit strict provenance lints to the `kernel` crate to avoid complex
logic in the build system. This can be revisited on MSRV >= 1.84.0.
- Rebase on rust-next.
- Link to v3: https://lore.kernel.org/r/20250314-ptr-as-ptr-v3-0-e7ba61048f4a@gmail.com
Changes in v3:
- Fixed clippy warning in rust/kernel/firmware.rs. (kernel test robot)
Link: https://lore.kernel.org/all/202503120332.YTCpFEvv-lkp@intel.com/
- s/as u64/as bindings::phys_addr_t/g. (Benno Lossin)
- Use strict provenance APIs and enable lints. (Benno Lossin)
- Link to v2: https://lore.kernel.org/r/20250309-ptr-as-ptr-v2-0-25d60ad922b7@gmail.com
Changes in v2:
- Fixed typo in first commit message.
- Added additional patches, converted to series.
- Link to v1: https://lore.kernel.org/r/20250307-ptr-as-ptr-v1-1-582d06514c98@gmail.com
---
Tamir Duberstein (6):
rust: enable `clippy::ptr_as_ptr` lint
rust: enable `clippy::ptr_cast_constness` lint
rust: enable `clippy::as_ptr_cast_mut` lint
rust: enable `clippy::as_underscore` lint
rust: enable `clippy::cast_lossless` lint
rust: enable `clippy::ref_as_ptr` lint
Makefile | 6 ++++++
drivers/gpu/drm/drm_panic_qr.rs | 2 +-
rust/bindings/lib.rs | 3 +++
rust/kernel/alloc/allocator_test.rs | 2 +-
rust/kernel/alloc/kvec.rs | 4 ++--
rust/kernel/block/mq/operations.rs | 2 +-
rust/kernel/block/mq/request.rs | 6 +++---
rust/kernel/device.rs | 4 ++--
rust/kernel/device_id.rs | 4 ++--
rust/kernel/devres.rs | 19 ++++++++++---------
rust/kernel/dma.rs | 6 +++---
rust/kernel/error.rs | 2 +-
rust/kernel/firmware.rs | 3 ++-
rust/kernel/fs/file.rs | 2 +-
rust/kernel/io.rs | 18 +++++++++---------
rust/kernel/kunit.rs | 11 +++++++----
rust/kernel/list/impl_list_item_mod.rs | 2 +-
rust/kernel/miscdevice.rs | 2 +-
rust/kernel/net/phy.rs | 4 ++--
rust/kernel/of.rs | 6 +++---
rust/kernel/pci.rs | 11 +++++++----
rust/kernel/platform.rs | 4 +++-
rust/kernel/print.rs | 6 +++---
rust/kernel/seq_file.rs | 2 +-
rust/kernel/str.rs | 14 +++++++-------
rust/kernel/sync/poll.rs | 2 +-
rust/kernel/time/hrtimer/pin.rs | 2 +-
rust/kernel/time/hrtimer/pin_mut.rs | 2 +-
rust/kernel/uaccess.rs | 4 ++--
rust/kernel/workqueue.rs | 12 ++++++------
rust/uapi/lib.rs | 3 +++
31 files changed, 96 insertions(+), 74 deletions(-)
---
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
change-id: 20250307-ptr-as-ptr-21b1867fc4d4
prerequisite-change-id: 20250409-container-of-mutness-b153dab4388d:v1
prerequisite-patch-id: 53d5889db599267f87642bb0ae3063c29bc24863
Best regards,
--
Tamir Duberstein <tamird(a)gmail.com>
v7:
- Skip the vmscan change as the mem_cgroup_usage() check for now as
it is currently redundant.
v6:
- The memcg_test_low failure is indeed due to the memory_recursiveprot
mount option which is enabled by default in systemd cgroup v2 setting.
So adopt Michal's suggestion to adjust the low event checking
according to whether memory_recursiveprot is enabled or not.
v5:
- Use mem_cgroup_usage() in patch 1 as originally suggested by Johannes.
The test_memcontrol selftest consistently fails its test_memcg_low
sub-test (with memory_recursiveprot enabled) and sporadically fails
its test_memcg_min sub-test. This patchset fixes the test_memcg_min
and test_memcg_low failures by adjusting the test_memcontrol selftest
to fix these test failures.
Waiman Long (2):
selftests: memcg: Allow low event with no memory.low and
memory_recursiveprot on
selftests: memcg: Increase error tolerance of child memory.current
check in test_memcg_protection()
.../selftests/cgroup/test_memcontrol.c | 20 ++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
--
2.49.0
The guard regions feature was initially implemented to support anonymous
mappings only, excluding shmem.
This was done such as to introduce the feature carefully and incrementally
and to be conservative when considering the various caveats and corner
cases that are applicable to file-backed mappings but not to anonymous
ones.
Now this feature has landed in 6.13, it is time to revisit this and to
extend this functionality to file-backed and shmem mappings.
In order to make this maximally useful, and since one may map file-backed
mappings read-only (for instance ELF images), we also remove the
restriction on read-only mappings and permit the establishment of guard
regions in any non-hugetlb, non-mlock()'d mapping.
It is permissible to permit the establishment of guard regions in read-only
mappings because the guard regions only reduce access to the mapping, and
when removed simply reinstate the existing attributes of the underlying
VMA, meaning no access violations can occur.
While the change in kernel code introduced in this series is small, the
majority of the effort here is spent in extending the testing to assert
that the feature works correctly across numerous file-backed mapping
scenarios.
Every single guard region self-test performed against anonymous memory
(which is relevant and not anon-only) has now been updated to also be
performed against shmem and a mapping of a file in the working directory.
This confirms that all cases also function correctly for file-backed guard
regions.
In addition a number of other tests are added for specific file-backed
mapping scenarios.
There are a number of other concerns that one might have with regard to
guard regions, addressed below:
Readahead
~~~~~~~~~
Readahead is a process through which the page cache is populated on the
assumption that sequential reads will occur, thus amortising I/O and,
through a clever use of the PG_readahead folio flag establishing during
major fault and checked upon minor fault, provides for asynchronous I/O to
occur as dat is processed, reducing I/O stalls as data is faulted in.
Guard regions do not alter this mechanism which operations at the folio and
fault level, but do of course prevent the faulting of folios that would
otherwise be mapped.
In the instance of a major fault prior to a guard region, synchronous
readahead will occur including populating folios in the page cache which
the guard regions will, in the case of the mapping in question, prevent
access to.
In addition, if PG_readahead is placed in a folio that is now inaccessible,
this will prevent asynchronous readahead from occurring as it would
otherwise do.
However, there are mechanisms for heuristically resetting this within
readahead regardless, which will 'recover' correct readahead behaviour.
Readahead presumes sequential data access, the presence of a guard region
clearly indicates that, at least in the guard region, no such sequential
access will occur, as it cannot occur there.
So this should have very little impact on any real workload. The far more
important point is as to whether readahead causes incorrect or
inappropriate mapping of ranges disallowed by the presence of guard
regions - this is not the case, as readahead does not 'pre-fault' memory in
this fashion.
At any rate, any mechanism which would attempt to do so would hit the usual
page fault paths, which correctly handle PTE markers as with anonymous
mappings.
Fault-Around
~~~~~~~~~~~~
The fault-around logic, in a similar vein to readahead, attempts to improve
efficiency with regard to file-backed memory mappings, however it differs
in that it does not try to fetch folios into the page cache that are about
to be accessed, but rather pre-maps a range of folios around the faulting
address.
Guard regions making use of PTE markers makes this relatively trivial, as
this case is already handled - see filemap_map_folio_range() and
filemap_map_order0_folio() - in both instances, the solution is to simply
keep the established page table mappings and let the fault handler take
care of PTE markers, as per the comment:
/*
* NOTE: If there're PTE markers, we'll leave them to be
* handled in the specific fault path, and it'll prohibit
* the fault-around logic.
*/
This works, as establishing guard regions results in page table mappings
with PTE markers, and clearing them removes them.
Truncation
~~~~~~~~~~
File truncation will not eliminate existing guard regions, as the
truncation operation will ultimately zap the range via
unmap_mapping_range(), which specifically excludes PTE markers.
Zapping
~~~~~~~
Zapping is, as with anonymous mappings, handled by zap_nonpresent_ptes(),
which specifically deals with guard entries, leaving them intact except in
instances such as process teardown or munmap() where they need to be
removed.
Reclaim
~~~~~~~
When reclaim is performed on file-backed folios, it ultimately invokes
try_to_unmap_one() via the rmap. If the folio is non-large, then map_pte()
will ultimately abort the operation for the guard region mapping. If large,
then check_pte() will determine that this is a non-device private
entry/device-exclusive entry 'swap' PTE and thus abort the operation in
that instance.
Therefore, no odd things happen in the instance of reclaim being attempted
upon a file-backed guard region.
Hole Punching
~~~~~~~~~~~~~
This updates the page cache and ultimately invokes unmap_mapping_range(),
which explicitly leaves PTE markers in place.
Because the establishment of guard regions zapped any existing mappings to
file-backed folios, once the guard regions are removed then the
hole-punched region will be faulted in as usual and everything will behave
as expected.
Lorenzo Stoakes (4):
mm: allow guard regions in file-backed and read-only mappings
selftests/mm: rename guard-pages to guard-regions
tools/selftests: expand all guard region tests to file-backed
tools/selftests: add file/shmem-backed mapping guard region tests
mm/madvise.c | 8 +-
tools/testing/selftests/mm/.gitignore | 2 +-
tools/testing/selftests/mm/Makefile | 2 +-
.../mm/{guard-pages.c => guard-regions.c} | 921 ++++++++++++++++--
4 files changed, 821 insertions(+), 112 deletions(-)
rename tools/testing/selftests/mm/{guard-pages.c => guard-regions.c} (58%)
--
2.48.1