From 0658a0961b0ace06b4cf0e1b73a4f20e349f4346 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Mon, 8 Nov 2021 18:31:30 -0800 Subject: procfs: do not list TID 0 in /proc//task If a task exits concurrently, task_pid_nr_ns may return 0. [akpm@linux-foundation.org: coding style tweaks] [adobriyan@gmail.com: test that /proc/*/task doesn't contain "0"] Link: https://lkml.kernel.org/r/YV88AnVzHxPafQ9o@localhost.localdomain Link: https://lkml.kernel.org/r/8735pn5dx7.fsf@oldenburg.str.redhat.com Signed-off-by: Florian Weimer Signed-off-by: Alexey Dobriyan Acked-by: Christian Brauner Reviewed-by: Alexey Dobriyan Cc: Kees Cook Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/selftests/proc/.gitignore | 1 + tools/testing/selftests/proc/Makefile | 2 + tools/testing/selftests/proc/proc-tid0.c | 81 ++++++++++++++++++++++++++++++++ 3 files changed, 84 insertions(+) create mode 100644 tools/testing/selftests/proc/proc-tid0.c (limited to 'tools/testing') diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore index 8f3e72e626fa..c4e6a34f9657 100644 --- a/tools/testing/selftests/proc/.gitignore +++ b/tools/testing/selftests/proc/.gitignore @@ -11,6 +11,7 @@ /proc-self-syscall /proc-self-wchan /proc-subset-pid +/proc-tid0 /proc-uptime-001 /proc-uptime-002 /read diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile index 1054e40a499a..219fc6113847 100644 --- a/tools/testing/selftests/proc/Makefile +++ b/tools/testing/selftests/proc/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only CFLAGS += -Wall -O2 -Wno-unused-function CFLAGS += -D_GNU_SOURCE +LDFLAGS += -pthread TEST_GEN_PROGS := TEST_GEN_PROGS += fd-001-lookup @@ -13,6 +14,7 @@ TEST_GEN_PROGS += proc-self-map-files-002 TEST_GEN_PROGS += proc-self-syscall TEST_GEN_PROGS += proc-self-wchan TEST_GEN_PROGS += proc-subset-pid +TEST_GEN_PROGS += proc-tid0 TEST_GEN_PROGS += proc-uptime-001 TEST_GEN_PROGS += proc-uptime-002 TEST_GEN_PROGS += read diff --git a/tools/testing/selftests/proc/proc-tid0.c b/tools/testing/selftests/proc/proc-tid0.c new file mode 100644 index 000000000000..58c1d7c90a8e --- /dev/null +++ b/tools/testing/selftests/proc/proc-tid0.c @@ -0,0 +1,81 @@ +/* + * Copyright (c) 2021 Alexey Dobriyan + * + * 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 that /proc/*/task never contains "0". +#include +#include +#include +#include +#include +#include +#include +#include + +static pid_t pid = -1; + +static void atexit_hook(void) +{ + if (pid > 0) { + kill(pid, SIGKILL); + } +} + +static void *f(void *_) +{ + return NULL; +} + +static void sigalrm(int _) +{ + exit(0); +} + +int main(void) +{ + pid = fork(); + if (pid == 0) { + /* child */ + while (1) { + pthread_t pth; + pthread_create(&pth, NULL, f, NULL); + pthread_join(pth, NULL); + } + } else if (pid > 0) { + /* parent */ + atexit(atexit_hook); + + char buf[64]; + snprintf(buf, sizeof(buf), "/proc/%u/task", pid); + + signal(SIGALRM, sigalrm); + alarm(1); + + while (1) { + DIR *d = opendir(buf); + struct dirent *de; + while ((de = readdir(d))) { + if (strcmp(de->d_name, "0") == 0) { + exit(1); + } + } + closedir(d); + } + + return 0; + } else { + perror("fork"); + return 1; + } +} -- cgit v1.2.3 From 303f8e2d02002dbe331cab7813ee091aead3cd39 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Mon, 8 Nov 2021 18:35:56 -0800 Subject: selftests/kselftest/runner/run_one(): allow running non-executable files When running a test program, 'run_one()' checks if the program has the execution permission and fails if it doesn't. However, it's easy to mistakenly lose the permissions, as some common tools like 'diff' don't support the permission change well[1]. Compared to that, making mistakes in the test program's path would only rare, as those are explicitly listed in 'TEST_PROGS'. Therefore, it might make more sense to resolve the situation on our own and run the program. For this reason, this commit makes the test program runner function still print the warning message but to try parsing the interpreter of the program and to explicitly run it with the interpreter, in this case. [1] https://lore.kernel.org/mm-commits/YRJisBs9AunccCD4@kroah.com/ Link: https://lkml.kernel.org/r/20210810164534.25902-1-sj38.park@gmail.com Signed-off-by: SeongJae Park Suggested-by: Greg Kroah-Hartman Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/selftests/kselftest/runner.sh | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) (limited to 'tools/testing') diff --git a/tools/testing/selftests/kselftest/runner.sh b/tools/testing/selftests/kselftest/runner.sh index cc9c846585f0..a9ba782d8ca0 100644 --- a/tools/testing/selftests/kselftest/runner.sh +++ b/tools/testing/selftests/kselftest/runner.sh @@ -33,9 +33,9 @@ tap_timeout() { # Make sure tests will time out if utility is available. if [ -x /usr/bin/timeout ] ; then - /usr/bin/timeout --foreground "$kselftest_timeout" "$1" + /usr/bin/timeout --foreground "$kselftest_timeout" $1 else - "$1" + $1 fi } @@ -65,17 +65,25 @@ run_one() TEST_HDR_MSG="selftests: $DIR: $BASENAME_TEST" echo "# $TEST_HDR_MSG" - if [ ! -x "$TEST" ]; then - echo -n "# Warning: file $TEST is " - if [ ! -e "$TEST" ]; then - echo "missing!" - else - echo "not executable, correct this." - fi + if [ ! -e "$TEST" ]; then + echo "# Warning: file $TEST is missing!" echo "not ok $test_num $TEST_HDR_MSG" else + cmd="./$BASENAME_TEST" + if [ ! -x "$TEST" ]; then + echo "# Warning: file $TEST is not executable" + + if [ $(head -n 1 "$TEST" | cut -c -2) = "#!" ] + then + interpreter=$(head -n 1 "$TEST" | cut -c 3-) + cmd="$interpreter ./$BASENAME_TEST" + else + echo "not ok $test_num $TEST_HDR_MSG" + return + fi + fi cd `dirname $TEST` > /dev/null - ((((( tap_timeout ./$BASENAME_TEST 2>&1; echo $? >&3) | + ((((( tap_timeout "$cmd" 2>&1; echo $? >&3) | tap_prefix >&4) 3>&1) | (read xs; exit $xs)) 4>>"$logfile" && echo "ok $test_num $TEST_HDR_MSG") || -- cgit v1.2.3