From 3b5992eaf730bf6c48e2dc8b4ebf360c43e973a7 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Mon, 7 Oct 2024 23:45:56 +0200 Subject: selftests: vDSO: unconditionally build chacha test Rather than using symlinks to find the vgetrandom-chacha.S file for each arch, store this in a file that uses the compiler to determine architecture, and then make use of weak symbols to skip the test on architectures that don't provide the code. Signed-off-by: Jason A. Donenfeld Signed-off-by: Shuah Khan --- tools/arch/arm64/vdso | 1 - tools/arch/loongarch/vdso | 1 - tools/arch/powerpc/vdso | 1 - tools/arch/s390/vdso | 1 - tools/arch/x86/vdso | 1 - tools/testing/selftests/vDSO/Makefile | 6 +++--- tools/testing/selftests/vDSO/vdso_test_chacha.c | 9 +++++---- tools/testing/selftests/vDSO/vgetrandom-chacha.S | 18 ++++++++++++++++++ 8 files changed, 26 insertions(+), 12 deletions(-) delete mode 120000 tools/arch/arm64/vdso delete mode 120000 tools/arch/loongarch/vdso delete mode 120000 tools/arch/powerpc/vdso delete mode 120000 tools/arch/s390/vdso delete mode 120000 tools/arch/x86/vdso create mode 100644 tools/testing/selftests/vDSO/vgetrandom-chacha.S (limited to 'tools') diff --git a/tools/arch/arm64/vdso b/tools/arch/arm64/vdso deleted file mode 120000 index 233c7a26f6e5..000000000000 --- a/tools/arch/arm64/vdso +++ /dev/null @@ -1 +0,0 @@ -../../../arch/arm64/kernel/vdso \ No newline at end of file diff --git a/tools/arch/loongarch/vdso b/tools/arch/loongarch/vdso deleted file mode 120000 index ebda43a82db7..000000000000 --- a/tools/arch/loongarch/vdso +++ /dev/null @@ -1 +0,0 @@ -../../../arch/loongarch/vdso \ No newline at end of file diff --git a/tools/arch/powerpc/vdso b/tools/arch/powerpc/vdso deleted file mode 120000 index 4e676d1d1cb4..000000000000 --- a/tools/arch/powerpc/vdso +++ /dev/null @@ -1 +0,0 @@ -../../../arch/powerpc/kernel/vdso \ No newline at end of file diff --git a/tools/arch/s390/vdso b/tools/arch/s390/vdso deleted file mode 120000 index 6cf4c1cebdcd..000000000000 --- a/tools/arch/s390/vdso +++ /dev/null @@ -1 +0,0 @@ -../../../arch/s390/kernel/vdso64 \ No newline at end of file diff --git a/tools/arch/x86/vdso b/tools/arch/x86/vdso deleted file mode 120000 index 7eb962fd3454..000000000000 --- a/tools/arch/x86/vdso +++ /dev/null @@ -1 +0,0 @@ -../../../arch/x86/entry/vdso/ \ No newline at end of file diff --git a/tools/testing/selftests/vDSO/Makefile b/tools/testing/selftests/vDSO/Makefile index af9cedbf5357..45641386c662 100644 --- a/tools/testing/selftests/vDSO/Makefile +++ b/tools/testing/selftests/vDSO/Makefile @@ -11,8 +11,8 @@ endif TEST_GEN_PROGS += vdso_test_correctness ifeq ($(ARCH)$(CONFIG_X86_32),$(filter $(ARCH)$(CONFIG_X86_32),x86 x86_64 loongarch arm64 powerpc s390)) TEST_GEN_PROGS += vdso_test_getrandom -TEST_GEN_PROGS += vdso_test_chacha endif +TEST_GEN_PROGS += vdso_test_chacha CFLAGS := -std=gnu99 -O2 @@ -37,9 +37,9 @@ $(OUTPUT)/vdso_test_getrandom: CFLAGS += -isystem $(top_srcdir)/tools/include \ $(KHDR_INCLUDES) \ -isystem $(top_srcdir)/include/uapi -$(OUTPUT)/vdso_test_chacha: $(top_srcdir)/tools/arch/$(SRCARCH)/vdso/vgetrandom-chacha.S +$(OUTPUT)/vdso_test_chacha: vgetrandom-chacha.S $(OUTPUT)/vdso_test_chacha: CFLAGS += -idirafter $(top_srcdir)/tools/include \ -idirafter $(top_srcdir)/tools/include/generated \ -idirafter $(top_srcdir)/arch/$(SRCARCH)/include \ -idirafter $(top_srcdir)/include \ - -D__ASSEMBLY__ -Wa,--noexecstack + -Wa,--noexecstack diff --git a/tools/testing/selftests/vDSO/vdso_test_chacha.c b/tools/testing/selftests/vDSO/vdso_test_chacha.c index b1ea532c5996..c66eb9df89bd 100644 --- a/tools/testing/selftests/vDSO/vdso_test_chacha.c +++ b/tools/testing/selftests/vDSO/vdso_test_chacha.c @@ -3,6 +3,7 @@ * Copyright (C) 2022-2024 Jason A. Donenfeld . All Rights Reserved. */ +#include #include #include #include @@ -73,10 +74,10 @@ static void reference_chacha20_blocks(uint8_t *dst_bytes, const uint32_t *key, u counter[1] = s[13]; } -typedef uint8_t u8; -typedef uint32_t u32; -typedef uint64_t u64; -#include +void __weak __arch_chacha20_blocks_nostack(uint8_t *dst_bytes, const uint32_t *key, uint32_t *counter, size_t nblocks) +{ + ksft_exit_skip("Not implemented on architecture\n"); +} int main(int argc, char *argv[]) { diff --git a/tools/testing/selftests/vDSO/vgetrandom-chacha.S b/tools/testing/selftests/vDSO/vgetrandom-chacha.S new file mode 100644 index 000000000000..d6e09af7c0a9 --- /dev/null +++ b/tools/testing/selftests/vDSO/vgetrandom-chacha.S @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2024 Jason A. Donenfeld . All Rights Reserved. + */ + +#define __ASSEMBLY__ + +#if defined(__aarch64__) +#include "../../../../arch/arm64/kernel/vdso/vgetrandom-chacha.S" +#elif defined(__loongarch__) +#include "../../../../arch/loongarch/vdso/vgetrandom-chacha.S" +#elif defined(__powerpc__) || defined(__powerpc64__) +#include "../../../../arch/powerpc/kernel/vdso/vgetrandom-chacha.S" +#elif defined(__s390x__) +#include "../../../../arch/s390/kernel/vdso64/vgetrandom-chacha.S" +#elif defined(__x86_64__) +#include "../../../../arch/x86/entry/vdso/vgetrandom-chacha.S" +#endif -- cgit v1.2.3 From fe6305cbc753766191da33b819f82f88986d3ca1 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Mon, 7 Oct 2024 23:45:57 +0200 Subject: selftests: vDSO: unconditionally build getrandom test Rather than building on supported archs, build on all archs, and then use the presence of the symbol in the vDSO to either skip the test or move forward with it. Note that this means that this test no longer checks whether the symbol was correctly added to the kernel. But hopefully this will be clear enough to developers and we'll cross our fingers that symbols aren't removed by accident and not caught after this change. Signed-off-by: Jason A. Donenfeld Signed-off-by: Shuah Khan --- tools/testing/selftests/vDSO/Makefile | 2 -- tools/testing/selftests/vDSO/vdso_test_getrandom.c | 2 +- 2 files changed, 1 insertion(+), 3 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vDSO/Makefile b/tools/testing/selftests/vDSO/Makefile index 45641386c662..1cf14a8da438 100644 --- a/tools/testing/selftests/vDSO/Makefile +++ b/tools/testing/selftests/vDSO/Makefile @@ -9,9 +9,7 @@ ifeq ($(ARCH),$(filter $(ARCH),x86 x86_64)) TEST_GEN_PROGS += vdso_standalone_test_x86 endif TEST_GEN_PROGS += vdso_test_correctness -ifeq ($(ARCH)$(CONFIG_X86_32),$(filter $(ARCH)$(CONFIG_X86_32),x86 x86_64 loongarch arm64 powerpc s390)) TEST_GEN_PROGS += vdso_test_getrandom -endif TEST_GEN_PROGS += vdso_test_chacha CFLAGS := -std=gnu99 -O2 diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c index e5e83dbec589..95ec894ac2d1 100644 --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c @@ -121,7 +121,7 @@ static void vgetrandom_init(void) vgrnd.fn = (__typeof__(vgrnd.fn))vdso_sym(version, name); if (!vgrnd.fn) { printf("%s is missing!\n", name); - exit(KSFT_FAIL); + exit(KSFT_SKIP); } ret = VDSO_CALL(vgrnd.fn, 5, NULL, 0, 0, &vgrnd.params, ~0UL); if (ret == -ENOSYS) { -- cgit v1.2.3 From 3953a1d1375247eafeeee24e69abb622f6acbd79 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Mon, 7 Oct 2024 23:45:58 +0200 Subject: selftests: vDSO: improve getrandom and chacha error messages Improve the error and skip condition messages to let the developer know precisely where a test has failed. Also make better use of the ksft api for this. Signed-off-by: Jason A. Donenfeld Signed-off-by: Shuah Khan --- tools/testing/selftests/vDSO/vdso_test_chacha.c | 27 ++++---- tools/testing/selftests/vDSO/vdso_test_getrandom.c | 75 ++++++++++------------ 2 files changed, 49 insertions(+), 53 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/vDSO/vdso_test_chacha.c b/tools/testing/selftests/vDSO/vdso_test_chacha.c index c66eb9df89bd..8757f738b0b1 100644 --- a/tools/testing/selftests/vDSO/vdso_test_chacha.c +++ b/tools/testing/selftests/vDSO/vdso_test_chacha.c @@ -91,10 +91,8 @@ int main(int argc, char *argv[]) ksft_set_plan(1); for (unsigned int trial = 0; trial < TRIALS; ++trial) { - if (getrandom(key, sizeof(key), 0) != sizeof(key)) { - printf("getrandom() failed!\n"); - return KSFT_SKIP; - } + if (getrandom(key, sizeof(key), 0) != sizeof(key)) + ksft_exit_skip("getrandom() failed unexpectedly\n"); memset(counter1, 0, sizeof(counter1)); reference_chacha20_blocks(output1, key, counter1, BLOCKS); for (unsigned int split = 0; split < BLOCKS; ++split) { @@ -103,8 +101,10 @@ int main(int argc, char *argv[]) if (split) __arch_chacha20_blocks_nostack(output2, key, counter2, split); __arch_chacha20_blocks_nostack(output2 + split * BLOCK_SIZE, key, counter2, BLOCKS - split); - if (memcmp(output1, output2, sizeof(output1)) || memcmp(counter1, counter2, sizeof(counter1))) - return KSFT_FAIL; + if (memcmp(output1, output2, sizeof(output1))) + ksft_exit_fail_msg("Main loop outputs do not match on trial %u, split %u\n", trial, split); + if (memcmp(counter1, counter2, sizeof(counter1))) + ksft_exit_fail_msg("Main loop counters do not match on trial %u, split %u\n", trial, split); } } memset(counter1, 0, sizeof(counter1)); @@ -114,14 +114,19 @@ int main(int argc, char *argv[]) reference_chacha20_blocks(output1, key, counter1, BLOCKS); __arch_chacha20_blocks_nostack(output2, key, counter2, BLOCKS); - if (memcmp(output1, output2, sizeof(output1)) || memcmp(counter1, counter2, sizeof(counter1))) - return KSFT_FAIL; + if (memcmp(output1, output2, sizeof(output1))) + ksft_exit_fail_msg("Block limit outputs do not match after first round\n"); + if (memcmp(counter1, counter2, sizeof(counter1))) + ksft_exit_fail_msg("Block limit counters do not match after first round\n"); reference_chacha20_blocks(output1, key, counter1, BLOCKS); __arch_chacha20_blocks_nostack(output2, key, counter2, BLOCKS); - if (memcmp(output1, output2, sizeof(output1)) || memcmp(counter1, counter2, sizeof(counter1))) - return KSFT_FAIL; + if (memcmp(output1, output2, sizeof(output1))) + ksft_exit_fail_msg("Block limit outputs do not match after second round\n"); + if (memcmp(counter1, counter2, sizeof(counter1))) + ksft_exit_fail_msg("Block limit counters do not match after second round\n"); ksft_test_result_pass("chacha: PASS\n"); - return KSFT_PASS; + ksft_exit_pass(); + return 0; } diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c index 95ec894ac2d1..da1210c4df02 100644 --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c @@ -40,6 +40,9 @@ } while (0) #endif +#define ksft_assert(condition) \ + do { if (!(condition)) ksft_exit_fail_msg("Assertion failed: %s\n", #condition); } while (0) + static struct { pthread_mutex_t lock; void **states; @@ -111,26 +114,19 @@ static void vgetrandom_init(void) const char *version = versions[VDSO_VERSION]; const char *name = names[VDSO_NAMES][6]; unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR); - size_t ret; + ssize_t ret; - if (!sysinfo_ehdr) { - printf("AT_SYSINFO_EHDR is not present!\n"); - exit(KSFT_SKIP); - } + if (!sysinfo_ehdr) + ksft_exit_skip("AT_SYSINFO_EHDR is not present\n"); vdso_init_from_sysinfo_ehdr(sysinfo_ehdr); vgrnd.fn = (__typeof__(vgrnd.fn))vdso_sym(version, name); - if (!vgrnd.fn) { - printf("%s is missing!\n", name); - exit(KSFT_SKIP); - } + if (!vgrnd.fn) + ksft_exit_skip("%s@%s symbol is missing from vDSO\n", name, version); ret = VDSO_CALL(vgrnd.fn, 5, NULL, 0, 0, &vgrnd.params, ~0UL); - if (ret == -ENOSYS) { - printf("unsupported architecture\n"); - exit(KSFT_SKIP); - } else if (ret) { - printf("failed to fetch vgetrandom params!\n"); - exit(KSFT_FAIL); - } + if (ret == -ENOSYS) + ksft_exit_skip("CPU does not have runtime support\n"); + else if (ret) + ksft_exit_fail_msg("Failed to fetch vgetrandom params: %zd\n", ret); } static ssize_t vgetrandom(void *buf, size_t len, unsigned long flags) @@ -139,10 +135,7 @@ static ssize_t vgetrandom(void *buf, size_t len, unsigned long flags) if (!state) { state = vgetrandom_get_state(); - if (!state) { - printf("vgetrandom_get_state failed!\n"); - exit(KSFT_FAIL); - } + ksft_assert(state); } return VDSO_CALL(vgrnd.fn, 5, buf, len, flags, state, vgrnd.params.size_of_opaque_state); } @@ -154,7 +147,7 @@ static void *test_vdso_getrandom(void *ctx) for (size_t i = 0; i < TRIALS; ++i) { unsigned int val; ssize_t ret = vgetrandom(&val, sizeof(val), 0); - assert(ret == sizeof(val)); + ksft_assert(ret == sizeof(val)); } return NULL; } @@ -164,7 +157,7 @@ static void *test_libc_getrandom(void *ctx) for (size_t i = 0; i < TRIALS; ++i) { unsigned int val; ssize_t ret = getrandom(&val, sizeof(val), 0); - assert(ret == sizeof(val)); + ksft_assert(ret == sizeof(val)); } return NULL; } @@ -174,7 +167,7 @@ static void *test_syscall_getrandom(void *ctx) for (size_t i = 0; i < TRIALS; ++i) { unsigned int val; ssize_t ret = syscall(__NR_getrandom, &val, sizeof(val), 0); - assert(ret == sizeof(val)); + ksft_assert(ret == sizeof(val)); } return NULL; } @@ -209,7 +202,7 @@ static void bench_multi(void) clock_gettime(CLOCK_MONOTONIC, &start); for (size_t i = 0; i < THREADS; ++i) - assert(pthread_create(&threads[i], NULL, test_vdso_getrandom, NULL) == 0); + ksft_assert(pthread_create(&threads[i], NULL, test_vdso_getrandom, NULL) == 0); for (size_t i = 0; i < THREADS; ++i) pthread_join(threads[i], NULL); clock_gettime(CLOCK_MONOTONIC, &end); @@ -218,7 +211,7 @@ static void bench_multi(void) clock_gettime(CLOCK_MONOTONIC, &start); for (size_t i = 0; i < THREADS; ++i) - assert(pthread_create(&threads[i], NULL, test_libc_getrandom, NULL) == 0); + ksft_assert(pthread_create(&threads[i], NULL, test_libc_getrandom, NULL) == 0); for (size_t i = 0; i < THREADS; ++i) pthread_join(threads[i], NULL); clock_gettime(CLOCK_MONOTONIC, &end); @@ -227,7 +220,7 @@ static void bench_multi(void) clock_gettime(CLOCK_MONOTONIC, &start); for (size_t i = 0; i < THREADS; ++i) - assert(pthread_create(&threads[i], NULL, test_syscall_getrandom, NULL) == 0); + ksft_assert(pthread_create(&threads[i], NULL, test_syscall_getrandom, NULL) == 0); for (size_t i = 0; i < THREADS; ++i) pthread_join(threads[i], NULL); clock_gettime(CLOCK_MONOTONIC, &end); @@ -252,48 +245,46 @@ static void kselftest(void) for (size_t i = 0; i < 1000; ++i) { ssize_t ret = vgetrandom(weird_size, sizeof(weird_size), 0); - if (ret != sizeof(weird_size)) - exit(KSFT_FAIL); + ksft_assert(ret == sizeof(weird_size)); } ksft_test_result_pass("getrandom: PASS\n"); unshare(CLONE_NEWUSER); - assert(unshare(CLONE_NEWTIME) == 0); + ksft_assert(unshare(CLONE_NEWTIME) == 0); child = fork(); - assert(child >= 0); + ksft_assert(child >= 0); if (!child) { vgetrandom_init(); child = getpid(); - assert(ptrace(PTRACE_TRACEME, 0, NULL, NULL) == 0); - assert(kill(child, SIGSTOP) == 0); - assert(vgetrandom(weird_size, sizeof(weird_size), 0) == sizeof(weird_size)); + ksft_assert(ptrace(PTRACE_TRACEME, 0, NULL, NULL) == 0); + ksft_assert(kill(child, SIGSTOP) == 0); + ksft_assert(vgetrandom(weird_size, sizeof(weird_size), 0) == sizeof(weird_size)); _exit(0); } for (;;) { struct ptrace_syscall_info info = { 0 }; int status, ret; - assert(waitpid(child, &status, 0) >= 0); + ksft_assert(waitpid(child, &status, 0) >= 0); if (WIFEXITED(status)) { - if (WEXITSTATUS(status) != 0) - exit(KSFT_FAIL); + ksft_assert(WEXITSTATUS(status) == 0); break; } - assert(WIFSTOPPED(status)); + ksft_assert(WIFSTOPPED(status)); if (WSTOPSIG(status) == SIGSTOP) - assert(ptrace(PTRACE_SETOPTIONS, child, 0, PTRACE_O_TRACESYSGOOD) == 0); + ksft_assert(ptrace(PTRACE_SETOPTIONS, child, 0, PTRACE_O_TRACESYSGOOD) == 0); else if (WSTOPSIG(status) == (SIGTRAP | 0x80)) { - assert(ptrace(PTRACE_GET_SYSCALL_INFO, child, sizeof(info), &info) > 0); + ksft_assert(ptrace(PTRACE_GET_SYSCALL_INFO, child, sizeof(info), &info) > 0); if (info.op == PTRACE_SYSCALL_INFO_ENTRY && info.entry.nr == __NR_getrandom && info.entry.args[0] == (uintptr_t)weird_size && info.entry.args[1] == sizeof(weird_size)) - exit(KSFT_FAIL); + ksft_exit_fail_msg("vgetrandom passed buffer to syscall getrandom unexpectedly\n"); } - assert(ptrace(PTRACE_SYSCALL, child, 0, 0) == 0); + ksft_assert(ptrace(PTRACE_SYSCALL, child, 0, 0) == 0); } ksft_test_result_pass("getrandom timens: PASS\n"); - exit(KSFT_PASS); + ksft_exit_pass(); } static void usage(const char *argv0) -- cgit v1.2.3 From 34d5b600172b846161e507bdce132c98d9cc9701 Mon Sep 17 00:00:00 2001 From: Yu Liao Date: Tue, 8 Oct 2024 10:33:32 +0800 Subject: selftests: vDSO: Explicitly include sched.h The previous commit introduced the use of CLONE_NEWTIME without including which contains its definition. Add an explicit include of to ensure that CLONE_NEWTIME is correctly defined before it is used. Fixes: 2aec90036dcd ("selftests: vDSO: ensure vgetrandom works in a time namespace") Signed-off-by: Yu Liao Signed-off-by: Shuah Khan --- tools/testing/selftests/vDSO/vdso_test_getrandom.c | 1 + 1 file changed, 1 insertion(+) (limited to 'tools') diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c index da1210c4df02..95057f7567db 100644 --- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c +++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include -- cgit v1.2.3 From a0cc649353bb726d4aa0db60dce467432197b746 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Tue, 8 Oct 2024 21:28:01 -0400 Subject: selftests/rseq: Fix mm_cid test failure Adapt the rseq.c/rseq.h code to follow GNU C library changes introduced by: glibc commit 2e456ccf0c34 ("Linux: Make __rseq_size useful for feature detection (bug 31965)") Without this fix, rseq selftests for mm_cid fail: ./run_param_test.sh Default parameters Running test spinlock Running compare-twice test spinlock Running mm_cid test spinlock Error: cpu id getter unavailable Fixes: 18c2355838e7 ("selftests/rseq: Implement rseq mm_cid field support") Signed-off-by: Mathieu Desnoyers Cc: Peter Zijlstra CC: Boqun Feng CC: "Paul E. McKenney" Cc: Shuah Khan CC: Carlos O'Donell CC: Florian Weimer CC: linux-kselftest@vger.kernel.org CC: stable@vger.kernel.org Signed-off-by: Shuah Khan --- tools/testing/selftests/rseq/rseq.c | 110 ++++++++++++++++++++++++------------ tools/testing/selftests/rseq/rseq.h | 10 +--- 2 files changed, 77 insertions(+), 43 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 96e812bdf8a4..5b9772cdf265 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -60,12 +60,6 @@ unsigned int rseq_size = -1U; /* Flags used during rseq registration. */ unsigned int rseq_flags; -/* - * rseq feature size supported by the kernel. 0 if the registration was - * unsuccessful. - */ -unsigned int rseq_feature_size = -1U; - static int rseq_ownership; static int rseq_reg_success; /* At least one rseq registration has succeded. */ @@ -111,6 +105,43 @@ int rseq_available(void) } } +/* The rseq areas need to be at least 32 bytes. */ +static +unsigned int get_rseq_min_alloc_size(void) +{ + unsigned int alloc_size = rseq_size; + + if (alloc_size < ORIG_RSEQ_ALLOC_SIZE) + alloc_size = ORIG_RSEQ_ALLOC_SIZE; + return alloc_size; +} + +/* + * Return the feature size supported by the kernel. + * + * Depending on the value returned by getauxval(AT_RSEQ_FEATURE_SIZE): + * + * 0: Return ORIG_RSEQ_FEATURE_SIZE (20) + * > 0: Return the value from getauxval(AT_RSEQ_FEATURE_SIZE). + * + * It should never return a value below ORIG_RSEQ_FEATURE_SIZE. + */ +static +unsigned int get_rseq_kernel_feature_size(void) +{ + unsigned long auxv_rseq_feature_size, auxv_rseq_align; + + auxv_rseq_align = getauxval(AT_RSEQ_ALIGN); + assert(!auxv_rseq_align || auxv_rseq_align <= RSEQ_THREAD_AREA_ALLOC_SIZE); + + auxv_rseq_feature_size = getauxval(AT_RSEQ_FEATURE_SIZE); + assert(!auxv_rseq_feature_size || auxv_rseq_feature_size <= RSEQ_THREAD_AREA_ALLOC_SIZE); + if (auxv_rseq_feature_size) + return auxv_rseq_feature_size; + else + return ORIG_RSEQ_FEATURE_SIZE; +} + int rseq_register_current_thread(void) { int rc; @@ -119,7 +150,7 @@ int rseq_register_current_thread(void) /* Treat libc's ownership as a successful registration. */ return 0; } - rc = sys_rseq(&__rseq_abi, rseq_size, 0, RSEQ_SIG); + rc = sys_rseq(&__rseq_abi, get_rseq_min_alloc_size(), 0, RSEQ_SIG); if (rc) { if (RSEQ_READ_ONCE(rseq_reg_success)) { /* Incoherent success/failure within process. */ @@ -140,28 +171,12 @@ int rseq_unregister_current_thread(void) /* Treat libc's ownership as a successful unregistration. */ return 0; } - rc = sys_rseq(&__rseq_abi, rseq_size, RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG); + rc = sys_rseq(&__rseq_abi, get_rseq_min_alloc_size(), RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG); if (rc) return -1; return 0; } -static -unsigned int get_rseq_feature_size(void) -{ - unsigned long auxv_rseq_feature_size, auxv_rseq_align; - - auxv_rseq_align = getauxval(AT_RSEQ_ALIGN); - assert(!auxv_rseq_align || auxv_rseq_align <= RSEQ_THREAD_AREA_ALLOC_SIZE); - - auxv_rseq_feature_size = getauxval(AT_RSEQ_FEATURE_SIZE); - assert(!auxv_rseq_feature_size || auxv_rseq_feature_size <= RSEQ_THREAD_AREA_ALLOC_SIZE); - if (auxv_rseq_feature_size) - return auxv_rseq_feature_size; - else - return ORIG_RSEQ_FEATURE_SIZE; -} - static __attribute__((constructor)) void rseq_init(void) { @@ -178,28 +193,54 @@ void rseq_init(void) } if (libc_rseq_size_p && libc_rseq_offset_p && libc_rseq_flags_p && *libc_rseq_size_p != 0) { + unsigned int libc_rseq_size; + /* rseq registration owned by glibc */ rseq_offset = *libc_rseq_offset_p; - rseq_size = *libc_rseq_size_p; + libc_rseq_size = *libc_rseq_size_p; rseq_flags = *libc_rseq_flags_p; - rseq_feature_size = get_rseq_feature_size(); - if (rseq_feature_size > rseq_size) - rseq_feature_size = rseq_size; + + /* + * Previous versions of glibc expose the value + * 32 even though the kernel only supported 20 + * bytes initially. Therefore treat 32 as a + * special-case. glibc 2.40 exposes a 20 bytes + * __rseq_size without using getauxval(3) to + * query the supported size, while still allocating a 32 + * bytes area. Also treat 20 as a special-case. + * + * Special-cases are handled by using the following + * value as active feature set size: + * + * rseq_size = min(32, get_rseq_kernel_feature_size()) + */ + switch (libc_rseq_size) { + case ORIG_RSEQ_FEATURE_SIZE: + fallthrough; + case ORIG_RSEQ_ALLOC_SIZE: + { + unsigned int rseq_kernel_feature_size = get_rseq_kernel_feature_size(); + + if (rseq_kernel_feature_size < ORIG_RSEQ_ALLOC_SIZE) + rseq_size = rseq_kernel_feature_size; + else + rseq_size = ORIG_RSEQ_ALLOC_SIZE; + break; + } + default: + /* Otherwise just use the __rseq_size from libc as rseq_size. */ + rseq_size = libc_rseq_size; + break; + } return; } rseq_ownership = 1; if (!rseq_available()) { rseq_size = 0; - rseq_feature_size = 0; return; } rseq_offset = (void *)&__rseq_abi - rseq_thread_pointer(); rseq_flags = 0; - rseq_feature_size = get_rseq_feature_size(); - if (rseq_feature_size == ORIG_RSEQ_FEATURE_SIZE) - rseq_size = ORIG_RSEQ_ALLOC_SIZE; - else - rseq_size = RSEQ_THREAD_AREA_ALLOC_SIZE; } static __attribute__((destructor)) @@ -209,7 +250,6 @@ void rseq_exit(void) return; rseq_offset = 0; rseq_size = -1U; - rseq_feature_size = -1U; rseq_ownership = 0; } diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h index d7364ea4d201..4e217b620e0c 100644 --- a/tools/testing/selftests/rseq/rseq.h +++ b/tools/testing/selftests/rseq/rseq.h @@ -68,12 +68,6 @@ extern unsigned int rseq_size; /* Flags used during rseq registration. */ extern unsigned int rseq_flags; -/* - * rseq feature size supported by the kernel. 0 if the registration was - * unsuccessful. - */ -extern unsigned int rseq_feature_size; - enum rseq_mo { RSEQ_MO_RELAXED = 0, RSEQ_MO_CONSUME = 1, /* Unused */ @@ -193,7 +187,7 @@ static inline uint32_t rseq_current_cpu(void) static inline bool rseq_node_id_available(void) { - return (int) rseq_feature_size >= rseq_offsetofend(struct rseq_abi, node_id); + return (int) rseq_size >= rseq_offsetofend(struct rseq_abi, node_id); } /* @@ -207,7 +201,7 @@ static inline uint32_t rseq_current_node_id(void) static inline bool rseq_mm_cid_available(void) { - return (int) rseq_feature_size >= rseq_offsetofend(struct rseq_abi, mm_cid); + return (int) rseq_size >= rseq_offsetofend(struct rseq_abi, mm_cid); } static inline uint32_t rseq_current_mm_cid(void) -- cgit v1.2.3 From 4ee5ca9a29384fcf3f18232fdf8474166dea8dca Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 10 Oct 2024 16:52:35 -0400 Subject: ftrace/selftest: Test combination of function_graph tracer and function profiler Masami reported a bug when running function graph tracing then the function profiler. The following commands would cause a kernel crash: # cd /sys/kernel/tracing/ # echo function_graph > current_tracer # echo 1 > function_profile_enabled In that order. Create a test to test this two to make sure this does not come back as a regression. Link: https://lore.kernel.org/172398528350.293426.8347220120333730248.stgit@devnote2 Link: https://lore.kernel.org/all/20241010165235.35122877@gandalf.local.home/ Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) Signed-off-by: Shuah Khan --- .../ftrace/test.d/ftrace/fgraph-profiler.tc | 31 ++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc (limited to 'tools') diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc new file mode 100644 index 000000000000..ffff8646733c --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-profiler.tc @@ -0,0 +1,31 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: ftrace - function profiler with function graph tracing +# requires: function_profile_enabled set_ftrace_filter function_graph:tracer + +# The function graph tracer can now be run along side of the function +# profiler. But there was a bug that caused the combination of the two +# to crash. It also required the function graph tracer to be started +# first. +# +# This test triggers that bug +# +# We need both function_graph and profiling to run this test + +fail() { # mesg + echo $1 + exit_fail +} + +echo "Enabling function graph tracer:" +echo function_graph > current_tracer +echo "enable profiler" + +# Older kernels do not allow function_profile to be enabled with +# function graph tracer. If the below fails, mark it as unsupported +echo 1 > function_profile_enabled || exit_unsupported + +# Let it run for a bit to make sure nothing explodes +sleep 1 + +exit 0 -- cgit v1.2.3