This patch will add the new test, which covers the prctl call with PR_SET_VMA command. The test tries to give a name to the anonymous VMA within the process memory map, and then checks the result of the operation by parsing 'maps' virtual file.

Additionally, the test tries to call the prctl PR_SET_VMA command with invalid arguments, and checks the error codes for correctness.

At the moment anonymous VMA naming through prctl call functionality is not covered with any tests, so I think implementing it makes sense.

In version 2 of this patch I consider the selftest Makefile rule about TARGETS entries order - I moved the 'prctl' entry in the Makefile to follow the lexicographic order. In version 1 it was placed at the end of the list.

Signed-off-by: Ivan Orlov ivan.orlov0322@gmail.com --- tools/testing/selftests/Makefile | 1 + tools/testing/selftests/prctl/.gitignore | 1 + tools/testing/selftests/prctl/Makefile | 2 +- tools/testing/selftests/prctl/config | 1 + .../selftests/prctl/set-anon-vma-name-test.c | 104 ++++++++++++++++++ 5 files changed, 108 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/prctl/config create mode 100644 tools/testing/selftests/prctl/set-anon-vma-name-test.c

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 13a6837a0c6b..97dcdaa656f6 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -58,6 +58,7 @@ TARGETS += nsfs TARGETS += pidfd TARGETS += pid_namespace TARGETS += powerpc +TARGETS += prctl TARGETS += proc TARGETS += pstore TARGETS += ptrace diff --git a/tools/testing/selftests/prctl/.gitignore b/tools/testing/selftests/prctl/.gitignore index 91af2b631bc9..7a657b25f686 100644 --- a/tools/testing/selftests/prctl/.gitignore +++ b/tools/testing/selftests/prctl/.gitignore @@ -2,3 +2,4 @@ disable-tsc-ctxt-sw-stress-test disable-tsc-on-off-stress-test disable-tsc-test +set-anon-vma-name-test diff --git a/tools/testing/selftests/prctl/Makefile b/tools/testing/selftests/prctl/Makefile index c7923b205222..c058b81eeb41 100644 --- a/tools/testing/selftests/prctl/Makefile +++ b/tools/testing/selftests/prctl/Makefile @@ -5,7 +5,7 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)

ifeq ($(ARCH),x86) TEST_PROGS := disable-tsc-ctxt-sw-stress-test disable-tsc-on-off-stress-test \ - disable-tsc-test + disable-tsc-test set-anon-vma-name-test all: $(TEST_PROGS)

include ../lib.mk diff --git a/tools/testing/selftests/prctl/config b/tools/testing/selftests/prctl/config new file mode 100644 index 000000000000..c6ed03c544e5 --- /dev/null +++ b/tools/testing/selftests/prctl/config @@ -0,0 +1 @@ +CONFIG_ANON_VMA_NAME=y diff --git a/tools/testing/selftests/prctl/set-anon-vma-name-test.c b/tools/testing/selftests/prctl/set-anon-vma-name-test.c new file mode 100644 index 000000000000..26d853c5a0c1 --- /dev/null +++ b/tools/testing/selftests/prctl/set-anon-vma-name-test.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This test covers the anonymous VMA naming functionality through prctl calls + */ + +#include <errno.h> +#include <sys/prctl.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/mman.h> +#include <string.h> + +#include "../kselftest_harness.h" + +#define AREA_SIZE 1024 + +#define GOOD_NAME "goodname" +#define BAD_NAME "badname\1" + +#ifndef PR_SET_VMA +#define PR_SET_VMA 0x53564d41 +#define PR_SET_VMA_ANON_NAME 0 +#endif + + +int rename_vma(unsigned long addr, unsigned long size, char *name) +{ + int res; + + res = prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, addr, size, name); + if (res < 0) + return -errno; + return res; +} + +int was_renaming_successful(char *target_name, unsigned long ptr) +{ + FILE *maps_file; + + char line_buf[512], name[128], mode[8]; + unsigned long start_addr, end_addr, offset; + unsigned int major_id, minor_id, node_id; + + char target_buf[128]; + int res = 0, sscanf_res; + + // The entry name in maps will be in format [anon:<target_name>] + sprintf(target_buf, "[anon:%s]", target_name); + maps_file = fopen("/proc/self/maps", "r"); + if (!maps_file) { + printf("## /proc/self/maps file opening error\n"); + return 0; + } + + // Parse the maps file to find the entry we renamed + while (fgets(line_buf, sizeof(line_buf), maps_file)) { + sscanf_res = sscanf(line_buf, "%lx-%lx %7s %lx %u:%u %u %s", &start_addr, + &end_addr, mode, &offset, &major_id, + &minor_id, &node_id, name); + if (sscanf_res == EOF) { + res = 0; + printf("## EOF while parsing the maps file\n"); + break; + } + if (!strcmp(name, target_buf) && start_addr == ptr) { + res = 1; + break; + } + } + fclose(maps_file); + return res; +} + +FIXTURE(vma) { + void *ptr_anon, *ptr_not_anon; +}; + +FIXTURE_SETUP(vma) { + self->ptr_anon = mmap(NULL, AREA_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, 0, 0); + ASSERT_NE(self->ptr_anon, NULL); + self->ptr_not_anon = mmap(NULL, AREA_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE, 0, 0); + ASSERT_NE(self->ptr_not_anon, NULL); +} + +FIXTURE_TEARDOWN(vma) { + munmap(self->ptr_anon, AREA_SIZE); + munmap(self->ptr_not_anon, AREA_SIZE); +} + +TEST_F(vma, renaming) { + TH_LOG("Try to rename the VMA with correct parameters"); + EXPECT_GE(rename_vma((unsigned long)self->ptr_anon, AREA_SIZE, GOOD_NAME), 0); + EXPECT_TRUE(was_renaming_successful(GOOD_NAME, (unsigned long)self->ptr_anon)); + + TH_LOG("Try to pass invalid name (with non-printable character \1) to rename the VMA"); + EXPECT_EQ(rename_vma((unsigned long)self->ptr_anon, AREA_SIZE, BAD_NAME), -EINVAL); + + TH_LOG("Try to rename non-anonynous VMA"); + EXPECT_EQ(rename_vma((unsigned long) self->ptr_not_anon, AREA_SIZE, GOOD_NAME), -EINVAL); +} + +TEST_HARNESS_MAIN