June 2025 - Linux-kselftest-mirror

[PATCH v3 0/6] KVM: guest_memfd: support for uffd minor

by Nikita Kalyazin

This series is built on top of the Fuad's v7 "mapping guest_memfd backed memory at the host" [1]. With James's KVM userfault [2], it is possible to handle stage-2 faults in guest_memfd in userspace. However, KVM itself also triggers faults in guest_memfd in some cases, for example: PV interfaces like kvmclock, PV EOI and page table walking code when fetching the MMIO instruction on x86. It was agreed in the guest_memfd upstream call on 23 Jan 2025 [3] that KVM would be accessing those pages via userspace page tables. In order for such faults to be handled in userspace, guest_memfd needs to support userfaultfd. Changes since v2 [4]: - James: Fix sgp type when calling shmem_get_folio_gfp - James: Improved vm_ops->fault() error handling - James: Add and make use of the can_userfault() VMA operation - James: Add UFFD_FEATURE_MINOR_GUEST_MEMFD feature flag - James: Fix typos and add more checks in the test Nikita [1] https://lore.kernel.org/kvm/20250318161823.4005529-1-tabba@google.com/T/ [2] https://lore.kernel.org/kvm/20250109204929.1106563-1-jthoughton@google.com/… [3] https://docs.google.com/document/d/1M6766BzdY1Lhk7LiR5IqVR8B8mG3cr-cxTxOrAo… [4] https://lore.kernel.org/kvm/20250402160721.97596-1-kalyazin@amazon.com/T/ Nikita Kalyazin (6): mm: userfaultfd: generic continue for non hugetlbfs mm: provide can_userfault vma operation mm: userfaultfd: use can_userfault vma operation KVM: guest_memfd: add support for userfaultfd minor mm: userfaultfd: add UFFD_FEATURE_MINOR_GUEST_MEMFD KVM: selftests: test userfaultfd minor for guest_memfd fs/userfaultfd.c | 3 +- include/linux/mm.h | 5 + include/linux/mm_types.h | 4 + include/linux/userfaultfd_k.h | 10 +- include/uapi/linux/userfaultfd.h | 8 +- mm/hugetlb.c | 9 +- mm/shmem.c | 17 +++- mm/userfaultfd.c | 47 ++++++--- .../testing/selftests/kvm/guest_memfd_test.c | 99 +++++++++++++++++++ virt/kvm/guest_memfd.c | 10 ++ 10 files changed, 188 insertions(+), 24 deletions(-) base-commit: 3cc51efc17a2c41a480eed36b31c1773936717e0 -- 2.47.1

5 months, 3 weeks

7
27
0 0

[PATCH] selftests/filesystems/mount-notify: remove __kernel_fsid_t

by Chen Linxuan

When build kernel selftests on Ubuntu 24.04, I got a compiler error: mount-notify_test.c:22:3: error: conflicting types for ‘__kernel_fsid_t’; have ‘struct <anonymous>’ 22 | } __kernel_fsid_t; | ^~~~~~~~~~~~~~~ In file included from .../linux/usr/include/asm/posix_types_64.h:18, from .../linux/usr/include/asm/posix_types.h:7, from .../linux/usr/include/linux/posix_types.h:36, from .../linux/usr/include/linux/types.h:9, from .../linux/usr/include/linux/stat.h:5, from /usr/include/x86_64-linux-gnu/bits/statx.h:31, from /usr/include/x86_64-linux-gnu/sys/stat.h:465, from mount-notify_test.c:9: .../linux/usr/include/asm-generic/posix_types.h:81:3: note: previous declaration of ‘__kernel_fsid_t’ with type ‘__kernel_fsid_t’ 81 | } __kernel_fsid_t; | ^~~~~~~~~~~~~~~ Signed-off-by: Chen Linxuan <chenlinxuan(a)uniontech.com> --- .../selftests/filesystems/mount-notify/mount-notify_test.c | 7 ------- .../filesystems/mount-notify/mount-notify_test_ns.c | 7 ------- 2 files changed, 14 deletions(-) diff --git a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c index b4cb494206e5d..2d197ad8cb75a 100644 --- a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c +++ b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c @@ -15,13 +15,6 @@ #include "../statmount/statmount.h" #include "../utils.h" -// Needed for linux/fanotify.h -#ifndef __kernel_fsid_t -typedef struct { - int val[2]; -} __kernel_fsid_t; -#endif - #include <sys/fanotify.h> static const char root_mntpoint_templ[] = "/tmp/mount-notify_test_root.XXXXXX"; diff --git a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test_ns.c b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test_ns.c index 1bd090e9c8dd5..d6a6a7ee87028 100644 --- a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test_ns.c +++ b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test_ns.c @@ -16,13 +16,6 @@ #include "../statmount/statmount.h" #include "../utils.h" -// Needed for linux/fanotify.h -#ifndef __kernel_fsid_t -typedef struct { - int val[2]; -} __kernel_fsid_t; -#endif - #include <sys/fanotify.h> static const char root_mntpoint_templ[] = "/tmp/mount-notify_test_root.XXXXXX"; -- 2.43.0

5 months, 3 weeks

2
1
0 0

[PATCH v3 00/16] kunit: Introduce UAPI testing framework

by Thomas Weißschuh

Currently testing of userspace and in-kernel API use two different frameworks. kselftests for the userspace ones and Kunit for the in-kernel ones. Besides their different scopes, both have different strengths and limitations: Kunit: * Tests are normal kernel code. * They use the regular kernel toolchain. * They can be packaged and distributed as modules conveniently. Kselftests: * Tests are normal userspace code * They need a userspace toolchain. A kernel cross toolchain is likely not enough. * A fair amout of userland is required to run the tests, which means a full distro or handcrafted rootfs. * There is no way to conveniently package and run kselftests with a given kernel image. * The kselftests makefiles are not as powerful as regular kbuild. For example they are missing proper header dependency tracking or more complex compiler option modifications. Therefore kunit is much easier to run against different kernel configurations and architectures. This series aims to combine kselftests and kunit, avoiding both their limitations. It works by compiling the userspace kselftests as part of the regular kernel build, embedding them into the kunit kernel or module and executing them from there. If the kernel toolchain is not fit to produce userspace because of a missing libc, the kernel's own nolibc can be used instead. The structured TAP output from the kselftest is integrated into the kunit KTAP output transparently, the kunit parser can parse the combined logs together. Further room for improvements: * Call each test in its completely dedicated namespace * Handle additional test files besides the test executable through archives. CPIO, cramfs, etc. * Compatibility with kselftest_harness.h (in progress) * Expose the blobs in debugfs * Provide some convience wrappers around compat userprogs * Figure out a migration path/coexistence solution for kunit UAPI and tools/testing/selftests/ Output from the kunit example testcase, note the output of "example_uapi_tests". $ ./tools/testing/kunit/kunit.py run --kunitconfig lib/kunit example ... Running tests with: $ .kunit/linux kunit.filter_glob=example kunit.enable=1 mem=1G console=tty kunit_shutdown=halt [11:53:53] ================== example (10 subtests) =================== [11:53:53] [PASSED] example_simple_test [11:53:53] [SKIPPED] example_skip_test [11:53:53] [SKIPPED] example_mark_skipped_test [11:53:53] [PASSED] example_all_expect_macros_test [11:53:53] [PASSED] example_static_stub_test [11:53:53] [PASSED] example_static_stub_using_fn_ptr_test [11:53:53] [PASSED] example_priv_test [11:53:53] =================== example_params_test =================== [11:53:53] [SKIPPED] example value 3 [11:53:53] [PASSED] example value 2 [11:53:53] [PASSED] example value 1 [11:53:53] [SKIPPED] example value 0 [11:53:53] =============== [PASSED] example_params_test =============== [11:53:53] [PASSED] example_slow_test [11:53:53] ======================= (4 subtests) ======================= [11:53:53] [PASSED] procfs [11:53:53] [PASSED] userspace test 2 [11:53:53] [SKIPPED] userspace test 3: some reason [11:53:53] [PASSED] userspace test 4 [11:53:53] ================ [PASSED] example_uapi_test ================ [11:53:53] ===================== [PASSED] example ===================== [11:53:53] ============================================================ [11:53:53] Testing complete. Ran 16 tests: passed: 11, skipped: 5 [11:53:53] Elapsed time: 67.543s total, 1.823s configuring, 65.655s building, 0.058s running Based on v6.15-rc1. Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de> --- Changes in v3: - Reintroduce CONFIG_CC_CAN_LINK_STATIC - Enable CONFIG_ARCH_HAS_NOLIBC for m68k and SPARC - Properly handle 'clean' target for userprogs - Use ramfs over tmpfs to reduce dependencies - Inherit userprogs byte order and ABI from kernel - Drop now unnecessary "#ifndef NOLIBC" - Pick up review tags - Drop usage of __private in blob.h, sparse complains and it is not really necessary - Fix execution on loongarch when using clang - Drop userprogs libgcc handling, it was ugly and is not yet necessary - Link to v2: https://lore.kernel.org/r/20250407-kunit-kselftests-v2-0-454114e287fd@linut… Changes in v2: - Rebase onto v6.15-rc1 - Add documentation and kernel docs - Resolve invalid kconfig breakages - Drop already applied patch "kbuild: implement CONFIG_HEADERS_INSTALL for Usermode Linux" - Drop userprogs CONFIG_WERROR integration, it doesn't need to be part of this series - Replace patch prefix "kconfig" with "kbuild" - Rename kunit_uapi_run_executable() to kunit_uapi_run_kselftest() - Generate private, conflict-free symbols in the blob framework - Handle kselftest exit codes - Handle SIGABRT - Forward output also to kunit debugfs log - Install a fd=0 stdin filedescriptor - Link to v1: https://lore.kernel.org/r/20250217-kunit-kselftests-v1-0-42b4524c3b0a@linut… --- Thomas Weißschuh (16): kbuild: userprogs: avoid duplicating of flags inherited from kernel kbuild: userprogs: also inherit byte order and ABI from kernel init: re-add CONFIG_CC_CAN_LINK_STATIC kbuild: userprogs: add nolibc support kbuild: introduce CONFIG_ARCH_HAS_NOLIBC kbuild: doc: add label for userprogs section kbuild: introduce blob framework kunit: tool: Add test for nested test result reporting kunit: tool: Don't overwrite test status based on subtest counts kunit: tool: Parse skipped tests from kselftest.h kunit: Always descend into kunit directory during build kunit: qemu_configs: loongarch: Enable LSX/LSAX kunit: Introduce UAPI testing framework kunit: uapi: Add example for UAPI tests kunit: uapi: Introduce preinit executable kunit: uapi: Validate usability of /proc Documentation/dev-tools/kunit/api/index.rst | 5 + Documentation/dev-tools/kunit/api/uapi.rst | 12 + Documentation/kbuild/makefiles.rst | 38 ++- MAINTAINERS | 2 + Makefile | 7 +- include/kunit/uapi.h | 24 ++ include/linux/blob.h | 31 +++ init/Kconfig | 7 + lib/Makefile | 4 - lib/kunit/Kconfig | 10 + lib/kunit/Makefile | 20 +- lib/kunit/kunit-example-test.c | 15 ++ lib/kunit/kunit-example-uapi.c | 54 ++++ lib/kunit/uapi-preinit.c | 63 +++++ lib/kunit/uapi.c | 294 +++++++++++++++++++++ scripts/Makefile.blobs | 19 ++ scripts/Makefile.build | 6 + scripts/Makefile.clean | 2 +- scripts/Makefile.userprogs | 13 +- scripts/blob-wrap.c | 27 ++ tools/include/nolibc/Kconfig.nolibc | 15 ++ tools/testing/kunit/kunit_parser.py | 13 +- tools/testing/kunit/kunit_tool_test.py | 9 + tools/testing/kunit/qemu_configs/loongarch.py | 2 + .../test_is_test_passed-failure-nested.log | 10 + .../test_data/test_is_test_passed-kselftest.log | 3 +- 26 files changed, 686 insertions(+), 19 deletions(-) --- base-commit: f07a3558c4a5d76f3fea004075e5151c4516d055 change-id: 20241015-kunit-kselftests-56273bc40442 Best regards, -- Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>

5 months, 3 weeks

4
43
0 0

[PATCH] selftests/nolibc: make stackprotector probing more robust

by Thomas Weißschuh

nolibc only supports symbol-based stackprotectors, based on the global variable __stack_chk_guard. Support for this differs between architectures and toolchains. Some use the symbol mode by default, some require a flag to enable it and some don't support it at all. Before the nolibc test Makefile required the availability of "-mstack-protector-guard=global" to enable stackprotectors. While this flag makes sure that the correct mode is available it doesn't work where the correct mode is the only supported one and therefore the flag is not implemented. Switch to a more dynamic probing mechanism. This correctly enables stack protectors for mips, loongarch and m68k. Signed-off-by: Thomas Weißschuh <linux(a)weissschuh.net> --- tools/testing/selftests/nolibc/Makefile | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile index 94176ffe46463548cc9bc787933b6cefa83d6502..853f3a846d4c0fb187922d3063ec3d1a9a30ae46 100644 --- a/tools/testing/selftests/nolibc/Makefile +++ b/tools/testing/selftests/nolibc/Makefile @@ -195,7 +195,10 @@ CFLAGS_sparc32 = $(call cc-option,-m32) ifeq ($(origin XARCH),command line) CFLAGS_XARCH = $(CFLAGS_$(XARCH)) endif -CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all)) +_CFLAGS_STACKPROTECTOR = $(call cc-option,-fstack-protector-all) $(call cc-option,-mstack-protector-guard=global) +CFLAGS_STACKPROTECTOR ?= $(call try-run, \ + echo 'void foo(void) {}' | $(CC) -x c - -o - -S $(_CFLAGS_STACKPROTECTOR) | grep -q __stack_chk_guard, \ + $(_CFLAGS_STACKPROTECTOR)) CFLAGS_SANITIZER ?= $(call cc-option,-fsanitize=undefined -fsanitize-trap=all) CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wextra \ $(call cc-option,-fno-stack-protector) $(call cc-option,-Wmissing-prototypes) \ --- base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494 change-id: 20250530-nolibc-stackprotector-robust-77c9f55a3921 Best regards, -- Thomas Weißschuh <linux(a)weissschuh.net>

5 months, 3 weeks

2
2
0 0

[PATCH 1/2] selftests: khugepaged: fix the shmem collapse failure

by Baolin Wang

When running the khugepaged selftest for shmem (./khugepaged all:shmem), I encountered the following test failures: " Run test: collapse_full (khugepaged:shmem) Collapse multiple fully populated PTE table.... Fail ... Run test: collapse_single_pte_entry (khugepaged:shmem) Collapse PTE table with single PTE entry present.... Fail ... Run test: collapse_full_of_compound (khugepaged:shmem) Allocate huge page... OK Split huge page leaving single PTE page table full of compound pages... OK Collapse PTE table full of compound pages.... Fail " The reason for the failure is that, it will set MADV_NOHUGEPAGE to prevent khugepaged from continuing to scan shmem VMA after khugepaged finishes scanning in the wait_for_scan() function. Moreover, shmem requires a refault to establish PMD mappings. However, after commit 2b0f922323cc, PMD mappings are prevented if the VMA is set with MADV_NOHUGEPAGE flag, so shmem cannot establish PMD mappings during refault. To fix this issue, we can set the MADV_NOHUGEPAGE flag after the shmem refault. With this fix, the shmem test case passes. Fixes: 2b0f922323cc ("mm: don't install PMD mappings when THPs are disabled by the hw/process/vma") Signed-off-by: Baolin Wang <baolin.wang(a)linux.alibaba.com> --- tools/testing/selftests/mm/khugepaged.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c index 8a4d34cce36b..d462f62d8116 100644 --- a/tools/testing/selftests/mm/khugepaged.c +++ b/tools/testing/selftests/mm/khugepaged.c @@ -561,8 +561,6 @@ static bool wait_for_scan(const char *msg, char *p, int nr_hpages, usleep(TICK); } - madvise(p, nr_hpages * hpage_pmd_size, MADV_NOHUGEPAGE); - return timeout == -1; } @@ -585,6 +583,7 @@ static void khugepaged_collapse(const char *msg, char *p, int nr_hpages, if (ops != &__anon_ops) ops->fault(p, 0, nr_hpages * hpage_pmd_size); + madvise(p, nr_hpages * hpage_pmd_size, MADV_NOHUGEPAGE); if (ops->check_huge(p, expect ? nr_hpages : 0)) success("OK"); else -- 2.43.5

5 months, 3 weeks

6
16
0 0

[PATCH RESEND] selftests/memfd: clean Makefile

by Chen Linxuan

When writing a test for fusectl, I referred to this Makefile as a reference for creating a FUSE daemon in the selftests. While doing so, I noticed that there is a minor issue in the Makefile. The fuse_mnt.c file is not actually compiled into fuse_mnt.o, and the code setting CFLAGS for it never takes effect. The reason fuse_mnt compiles successfully is because CFLAGS is set at the very beginning of the file. Signed-off-by: Chen Linxuan <chenlinxuan(a)uniontech.com> --- tools/testing/selftests/memfd/Makefile | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/tools/testing/selftests/memfd/Makefile b/tools/testing/selftests/memfd/Makefile index 163b6f68631c4..e9b886c65153d 100644 --- a/tools/testing/selftests/memfd/Makefile +++ b/tools/testing/selftests/memfd/Makefile @@ -1,5 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -CFLAGS += -D_FILE_OFFSET_BITS=64 CFLAGS += $(KHDR_INCLUDES) TEST_GEN_PROGS := memfd_test @@ -16,10 +15,9 @@ ifeq ($(VAR_LDLIBS),) VAR_LDLIBS := -lfuse -pthread endif -fuse_mnt.o: CFLAGS += $(VAR_CFLAGS) - include ../lib.mk +$(OUTPUT)/fuse_mnt: CFLAGS += $(VAR_CFLAGS) $(OUTPUT)/fuse_mnt: LDLIBS += $(VAR_LDLIBS) $(OUTPUT)/memfd_test: memfd_test.c common.c -- 2.43.0

5 months, 3 weeks

2
4
0 0

[PATCH RESEND] selftests: Suppress unused variable warning

by Chen Linxuan

When running `make kselftest`, the following compilation warning was encountered: mount-notify_test.c: In function ‘fanotify_rmdir’: mount-notify_test.c:490:17: warning: ignoring return value of ‘chdir’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 490 | chdir("/"); | ^~~~~~~~~~ This patch addresses the warning by explicitly suppressing the unused result of the `chdir` function. Signed-off-by: Chen Linxuan <chenlinxuan(a)uniontech.com> --- .../selftests/filesystems/mount-notify/mount-notify_test.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c index 63ce708d93ed0..34afe27b7978f 100644 --- a/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c +++ b/tools/testing/selftests/filesystems/mount-notify/mount-notify_test.c @@ -465,7 +465,9 @@ TEST_F(fanotify, rmdir) ASSERT_GE(ret, 0); if (ret == 0) { - chdir("/"); + // Suppress -Wunused-result + // Ref: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66425#c34 + (void) !chdir("/"); unshare(CLONE_NEWNS); mount("", "/", NULL, MS_REC|MS_PRIVATE, NULL); umount2("/a", MNT_DETACH); -- 2.43.0

5 months, 3 weeks

3
7
0 0

[PATCH net-next v4 0/4] netdevsim: implement RX statistics using NETDEV_PCPU_STAT_DSTATS

by Breno Leitao

The netdevsim driver previously lacked RX statistics support, which prevented its use with the GenerateTraffic() test framework, as this framework verifies traffic flow by checking RX byte counts. This patch migrates netdevsim from its custom statistics collection to the NETDEV_PCPU_STAT_DSTATS framework, as suggested by Jakub. This change not only standardizes the statistics handling but also adds the necessary RX statistics support required by the test framework. Signed-off-by: Breno Leitao <leitao(a)debian.org> --- Changes in v4: - Protect dev_dstats_rx_dropped_add() by disabling BH (Jakub) - Link to v3: https://lore.kernel.org/r/20250617-netdevsim_stat-v3-0-afe4bdcbf237@debian.… Changes in v3: - Rely on netdev from caller instead of napi->dev in nsim_queue_free(). - Link to v2: https://lore.kernel.org/r/20250613-netdevsim_stat-v2-0-98fa38836c48@debian.… Changes in v2: - Changed the RX collection place from nsim_napi_rx() to nsim_rcv (Joe Damato) - Collect RX dropped packets statistic in nsim_queue_free() (Jakub) - Added a helper in dstat to add values to RX dropped packets - Link to v1: https://lore.kernel.org/r/20250611-netdevsim_stat-v1-0-c11b657d96bf@debian.… --- Breno Leitao (4): netdevsim: migrate to dstats stats collection netdevsim: collect statistics at RX side net: add dev_dstats_rx_dropped_add() helper netdevsim: account dropped packet length in stats on queue free drivers/net/netdevsim/netdev.c | 56 ++++++++++++++++----------------------- drivers/net/netdevsim/netdevsim.h | 5 ---- include/linux/netdevice.h | 10 +++++++ 3 files changed, 33 insertions(+), 38 deletions(-) --- base-commit: 3b5b1c428260152e47c9584bc176f358b87ca82d change-id: 20250610-netdevsim_stat-95995921e03e Best regards, -- Breno Leitao <leitao(a)debian.org>

5 months, 3 weeks

2
5
0 0

[PATCH v2 2/2] selftests/bpf: Add testcases for BPF_ADD and BPF_SUB

by Harishankar Vishwanathan

The previous commit improves the precision in scalar(32)_min_max_add, and scalar(32)_min_max_sub. The improvement in precision occurs in cases when all outcomes overflow or underflow, respectively. This commit adds selftests that exercise those cases. Co-developed-by: Matan Shachnai <m.shachnai(a)rutgers.edu> Signed-off-by: Matan Shachnai <m.shachnai(a)rutgers.edu> Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan(a)gmail.com> --- .../selftests/bpf/progs/verifier_bounds.c | 85 +++++++++++++++++++ 1 file changed, 85 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/verifier_bounds.c b/tools/testing/selftests/bpf/progs/verifier_bounds.c index 30e16153fdf1..20fb0fef5719 100644 --- a/tools/testing/selftests/bpf/progs/verifier_bounds.c +++ b/tools/testing/selftests/bpf/progs/verifier_bounds.c @@ -1371,4 +1371,89 @@ __naked void mult_sign_ovf(void) __imm(bpf_skb_store_bytes) : __clobber_all); } + +SEC("socket") +__description("64-bit addition overflow, all outcomes overflow") +__success __log_level(2) +__msg("7: (0f) r5 += r3 {{.*}} R5_w=scalar(smin=0x800003d67e960f7d,umin=0x551ee3d67e960f7d,umax=0xc0149fffffffffff,smin32=0xfe960f7d,umin32=0x7e960f7d,var_off=(0x3d67e960f7d; 0xfffffc298169f082))") +__retval(0) +__naked void add64_ovf(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "r3 = r0;" + "r4 = 0x950a43d67e960f7d ll;" + "r3 |= r4;" + "r5 = 0xc014a00000000000 ll;" + "r5 += r3;" + "r0 = 0;" + "exit" + : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +SEC("socket") +__description("32-bit addition overflow, all outcomes overflow") +__success __log_level(2) +__msg("5: (0c) w5 += w3 {{.*}} R5_w=scalar(smin=umin=umin32=0x20130018,smax=umax=umax32=0x8000ffff,smin32=0x80000018,var_off=(0x18; 0xffffffe7))") +__retval(0) +__naked void add32_ovf(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "r3 = r0;" + "w4 = 0xa0120018;" + "w3 |= w4;" + "w5 = 0x80010000;" + "w5 += w3;" + "r0 = 0;" + "exit" + : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +SEC("socket") +__description("64-bit subtraction overflow, all outcomes underflow") +__success __log_level(2) +__msg("6: (1f) r3 -= r1 {{.*}} R3_w=scalar(umin=1,umax=0x8000000000000000)") +__retval(0) +__naked void sub64_ovf(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "r1 = r0;" + "r2 = 0x8000000000000000 ll;" + "r1 |= r2;" + "r3 = 0x0;" + "r3 -= r1;" + "r0 = 0;" + "exit" + : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +SEC("socket") +__description("32-bit subtraction overflow, all outcomes underflow") +__success __log_level(2) +__msg("5: (1c) w3 -= w1 {{.*}} R3_w=scalar(smin=umin=umin32=1,smax=umax=umax32=0x80000000,var_off=(0x0; 0xffffffff))") +__retval(0) +__naked void sub32_ovf(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "r1 = r0;" + "w2 = 0x80000000;" + "w1 |= w2;" + "r3 = 0x0;" + "w3 -= w1;" + "r0 = 0;" + "exit" + : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + char _license[] SEC("license") = "GPL"; -- 2.45.2

5 months, 3 weeks

2
4
0 0

[PATCH 0/2] mm/damon: fix memory leak in memcg_path sysfs file

by SeongJae Park

Users can leak memory by repeatedly writing a string to DAMOS sysfs memcg_path file. Fix it (patch 1) and add a selftest (patch 2) to avoid reoccurrance of the bug. SeongJae Park (2): mm/damon/sysfs-schemes: free old damon_sysfs_scheme_filter->memcg_path on write selftets/damon: add a test for memcg_path leak mm/damon/sysfs-schemes.c | 1 + tools/testing/selftests/damon/Makefile | 1 + .../selftests/damon/sysfs_memcg_path_leak.sh | 43 +++++++++++++++++++ 3 files changed, 45 insertions(+) create mode 100755 tools/testing/selftests/damon/sysfs_memcg_path_leak.sh base-commit: 05b89e828eb4f791f721cbdc65f36e1a8287a9d3 -- 2.39.5

5 months, 3 weeks

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Linux-kselftest-mirror June 2025