From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- tools/testing/selftests/fchmodat2/.gitignore | 2 + tools/testing/selftests/fchmodat2/Makefile | 15 ++ tools/testing/selftests/fchmodat2/fchmodat2_test.c | 200 +++++++++++++++++++++ 3 files changed, 217 insertions(+) create mode 100644 tools/testing/selftests/fchmodat2/.gitignore create mode 100644 tools/testing/selftests/fchmodat2/Makefile create mode 100644 tools/testing/selftests/fchmodat2/fchmodat2_test.c (limited to 'tools/testing/selftests/fchmodat2') diff --git a/tools/testing/selftests/fchmodat2/.gitignore b/tools/testing/selftests/fchmodat2/.gitignore new file mode 100644 index 000000000..82a4846cb --- /dev/null +++ b/tools/testing/selftests/fchmodat2/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +/*_test diff --git a/tools/testing/selftests/fchmodat2/Makefile b/tools/testing/selftests/fchmodat2/Makefile new file mode 100644 index 000000000..4373cea79 --- /dev/null +++ b/tools/testing/selftests/fchmodat2/Makefile @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0-or-later + +CFLAGS += -Wall -O2 -g -fsanitize=address -fsanitize=undefined $(KHDR_INCLUDES) + +# gcc requires -static-libasan in order to ensure that Address Sanitizer's +# library is the first one loaded. However, clang already statically links the +# Address Sanitizer if -fsanitize is specified. Therefore, simply omit +# -static-libasan for clang builds. +ifeq ($(LLVM),) + CFLAGS += -static-libasan +endif + +TEST_GEN_PROGS := fchmodat2_test + +include ../lib.mk diff --git a/tools/testing/selftests/fchmodat2/fchmodat2_test.c b/tools/testing/selftests/fchmodat2/fchmodat2_test.c new file mode 100644 index 000000000..8e1b6384b --- /dev/null +++ b/tools/testing/selftests/fchmodat2/fchmodat2_test.c @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#define _GNU_SOURCE +#include +#include +#include +#include +#include + +#include "kselftest.h" + +struct testdir { + char *dirname; + int dfd; +}; + +int sys_fchmodat2(int dfd, const char *filename, mode_t mode, int flags) +{ + int ret = syscall(__NR_fchmodat2, dfd, filename, mode, flags); + + return ret >= 0 ? ret : -errno; +} + +static void setup_testdir(struct testdir *testdir) +{ + int ret, dfd; + char dirname[] = "/tmp/ksft-fchmodat2.XXXXXX"; + + /* Make the top-level directory. */ + if (!mkdtemp(dirname)) + ksft_exit_fail_msg("%s: failed to create tmpdir\n", __func__); + + dfd = open(dirname, O_PATH | O_DIRECTORY); + if (dfd < 0) { + ksft_perror("failed to open tmpdir"); + goto err; + } + + ret = openat(dfd, "regfile", O_CREAT | O_WRONLY | O_TRUNC, 0644); + if (ret < 0) { + ksft_perror("failed to create file in tmpdir"); + goto err; + } + close(ret); + + ret = symlinkat("regfile", dfd, "symlink"); + if (ret < 0) { + ksft_perror("symlinkat() failed"); + goto err_regfile; + } + + testdir->dirname = strdup(dirname); + if (!testdir->dirname) { + ksft_perror("Out of memory"); + goto err_symlink; + } + testdir->dfd = dfd; + + return; + +err_symlink: + unlinkat(testdir->dfd, "symlink", 0); +err_regfile: + unlinkat(testdir->dfd, "regfile", 0); +err: + unlink(dirname); + ksft_exit_fail(); +} + +static void cleanup_testdir(struct testdir *testdir) +{ + unlinkat(testdir->dfd, "regfile", 0); + unlinkat(testdir->dfd, "symlink", 0); + rmdir(testdir->dirname); + free(testdir->dirname); +} + +int expect_mode(int dfd, const char *filename, mode_t expect_mode) +{ + struct stat st; + int ret = fstatat(dfd, filename, &st, AT_SYMLINK_NOFOLLOW); + + if (ret) { + ksft_perror("fstatat() failed\n"); + return 0; + } + + return (st.st_mode == expect_mode); +} + +void test_regfile(void) +{ + struct testdir testdir; + int ret; + + setup_testdir(&testdir); + + ret = sys_fchmodat2(testdir.dfd, "regfile", 0640, 0); + + if (ret < 0) { + ksft_perror("fchmodat2(noflag) failed"); + goto out; + } + + if (!expect_mode(testdir.dfd, "regfile", 0100640)) { + ksft_print_msg("%s: wrong file mode bits after fchmodat2\n", + __func__); + ret = 1; + goto out; + } + + ret = sys_fchmodat2(testdir.dfd, "regfile", 0600, AT_SYMLINK_NOFOLLOW); + + if (ret < 0) { + ksft_perror("fchmodat2(AT_SYMLINK_NOFOLLOW) failed"); + goto out; + } + + if (!expect_mode(testdir.dfd, "regfile", 0100600)) { + ksft_print_msg("%s: wrong file mode bits after fchmodat2 with nofollow\n", + __func__); + ret = 1; + } + +out: + ksft_test_result(ret == 0, "fchmodat2(regfile)\n"); + cleanup_testdir(&testdir); +} + +void test_symlink(void) +{ + struct testdir testdir; + int ret; + + setup_testdir(&testdir); + + ret = sys_fchmodat2(testdir.dfd, "symlink", 0640, 0); + + if (ret < 0) { + ksft_perror("fchmodat2(noflag) failed"); + goto err; + } + + if (!expect_mode(testdir.dfd, "regfile", 0100640)) { + ksft_print_msg("%s: wrong file mode bits after fchmodat2\n", + __func__); + goto err; + } + + if (!expect_mode(testdir.dfd, "symlink", 0120777)) { + ksft_print_msg("%s: wrong symlink mode bits after fchmodat2\n", + __func__); + goto err; + } + + ret = sys_fchmodat2(testdir.dfd, "symlink", 0600, AT_SYMLINK_NOFOLLOW); + + /* + * On certain filesystems (xfs or btrfs), chmod operation fails. So we + * first check the symlink target but if the operation fails we mark the + * test as skipped. + * + * https://sourceware.org/legacy-ml/libc-alpha/2020-02/msg00467.html + */ + if (ret == 0 && !expect_mode(testdir.dfd, "symlink", 0120600)) { + ksft_print_msg("%s: wrong symlink mode bits after fchmodat2 with nofollow\n", + __func__); + ret = 1; + goto err; + } + + if (!expect_mode(testdir.dfd, "regfile", 0100640)) { + ksft_print_msg("%s: wrong file mode bits after fchmodat2 with nofollow\n", + __func__); + } + + if (ret != 0) + ksft_test_result_skip("fchmodat2(symlink)\n"); + else + ksft_test_result_pass("fchmodat2(symlink)\n"); + cleanup_testdir(&testdir); + return; + +err: + ksft_test_result_fail("fchmodat2(symlink)\n"); + cleanup_testdir(&testdir); +} + +#define NUM_TESTS 2 + +int main(int argc, char **argv) +{ + ksft_print_header(); + ksft_set_plan(NUM_TESTS); + + test_regfile(); + test_symlink(); + + ksft_finished(); +} -- cgit v1.3.1