From: Alexey Dobriyan <adobriyan@xxxxxxxxx> Subject: proc: fix /proc/*/map_files lookup some more I totally forgot that _parse_integer() accepts arbitrary amount of leading zeroes leading to the following lookups: OK # readlink /proc/1/map_files/56427ecba000-56427eddc000 /lib/systemd/systemd bogus # readlink /proc/1/map_files/00000000000056427ecba000-56427eddc000 /lib/systemd/systemd # readlink /proc/1/map_files/56427ecba000-00000000000056427eddc000 /lib/systemd/systemd Link: http://lkml.kernel.org/r/20180303215130.GA23480@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Reviewed-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/base.c | 4 tools/testing/selftests/proc/.gitignore | 4 tools/testing/selftests/proc/Makefile | 2 tools/testing/selftests/proc/proc-self-map-files-001.c | 82 +++++++++ tools/testing/selftests/proc/proc-self-map-files-002.c | 85 ++++++++++ 5 files changed, 176 insertions(+), 1 deletion(-) diff -puN fs/proc/base.c~proc-fix-proc-map_files-lookup-some-more fs/proc/base.c --- a/fs/proc/base.c~proc-fix-proc-map_files-lookup-some-more +++ a/fs/proc/base.c @@ -1913,6 +1913,8 @@ static int dname_to_vma_addr(struct dent unsigned long long sval, eval; unsigned int len; + if (str[0] == '0' && str[1] != '-') + return -EINVAL; len = _parse_integer(str, 16, &sval); if (len & KSTRTOX_OVERFLOW) return -EINVAL; @@ -1924,6 +1926,8 @@ static int dname_to_vma_addr(struct dent return -EINVAL; str++; + if (str[0] == '0' && str[1]) + return -EINVAL; len = _parse_integer(str, 16, &eval); if (len & KSTRTOX_OVERFLOW) return -EINVAL; diff -puN tools/testing/selftests/proc/.gitignore~proc-fix-proc-map_files-lookup-some-more tools/testing/selftests/proc/.gitignore --- a/tools/testing/selftests/proc/.gitignore~proc-fix-proc-map_files-lookup-some-more +++ a/tools/testing/selftests/proc/.gitignore @@ -1,2 +1,4 @@ -/proc-self-mem +/proc-self-map-files-001 +/proc-self-map-files-002 /proc-self-syscall +/proc-self-wchan diff -puN tools/testing/selftests/proc/Makefile~proc-fix-proc-map_files-lookup-some-more tools/testing/selftests/proc/Makefile --- a/tools/testing/selftests/proc/Makefile~proc-fix-proc-map_files-lookup-some-more +++ a/tools/testing/selftests/proc/Makefile @@ -1,6 +1,8 @@ CFLAGS += -Wall -O2 TEST_GEN_PROGS := +TEST_GEN_PROGS += proc-self-map-files-001 +TEST_GEN_PROGS += proc-self-map-files-002 TEST_GEN_PROGS += proc-self-syscall TEST_GEN_PROGS += proc-self-wchan diff -puN /dev/null tools/testing/selftests/proc/proc-self-map-files-001.c --- /dev/null +++ a/tools/testing/selftests/proc/proc-self-map-files-001.c @@ -0,0 +1,82 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@xxxxxxxxx> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test readlink /proc/self/map_files/... */ +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <stdlib.h> + +static void pass(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1) + exit(1); +} + +static void fail(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT) + return; + exit(1); +} + +int main(void) +{ + const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE); + void *p; + int fd; + unsigned long a, b; + + fd = open("/dev/zero", O_RDONLY); + if (fd == -1) + return 1; + + p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0); + if (p == MAP_FAILED) + return 1; + + a = (unsigned long)p; + b = (unsigned long)p + PAGE_SIZE; + + pass("/proc/self/map_files/%lx-%lx", a, b); + fail("/proc/self/map_files/ %lx-%lx", a, b); + fail("/proc/self/map_files/%lx -%lx", a, b); + fail("/proc/self/map_files/%lx- %lx", a, b); + fail("/proc/self/map_files/%lx-%lx ", a, b); + fail("/proc/self/map_files/0%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-0%lx", a, b); + if (sizeof(long) == 4) { + fail("/proc/self/map_files/100000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-100000000%lx", a, b); + } else if (sizeof(long) == 8) { + fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b); + } else + return 1; + + return 0; +} diff -puN /dev/null tools/testing/selftests/proc/proc-self-map-files-002.c --- /dev/null +++ a/tools/testing/selftests/proc/proc-self-map-files-002.c @@ -0,0 +1,85 @@ +/* + * Copyright _ 2018 Alexey Dobriyan <adobriyan@xxxxxxxxx> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test readlink /proc/self/map_files/... with address 0. */ +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <stdlib.h> + +static void pass(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1) + exit(1); +} + +static void fail(const char *fmt, unsigned long a, unsigned long b) +{ + char name[64]; + char buf[64]; + + snprintf(name, sizeof(name), fmt, a, b); + if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT) + return; + exit(1); +} + +int main(void) +{ + const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE); + void *p; + int fd; + unsigned long a, b; + + fd = open("/dev/zero", O_RDONLY); + if (fd == -1) + return 1; + + p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0); + if (p == MAP_FAILED) { + if (errno == EPERM) + return 2; + return 1; + } + + a = (unsigned long)p; + b = (unsigned long)p + PAGE_SIZE; + + pass("/proc/self/map_files/%lx-%lx", a, b); + fail("/proc/self/map_files/ %lx-%lx", a, b); + fail("/proc/self/map_files/%lx -%lx", a, b); + fail("/proc/self/map_files/%lx- %lx", a, b); + fail("/proc/self/map_files/%lx-%lx ", a, b); + fail("/proc/self/map_files/0%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-0%lx", a, b); + if (sizeof(long) == 4) { + fail("/proc/self/map_files/100000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-100000000%lx", a, b); + } else if (sizeof(long) == 8) { + fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b); + fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b); + } else + return 1; + + return 0; +} _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
