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f08db42b1c
Commit ebb3f994dd ("mm/damon/dbgfs: fix 'struct pid' leaks in
'dbgfs_target_ids_write()'") fixes a pid leak bug in DAMON debugfs
interface, namely dbgfs_target_ids_write() function. Add a selftest for
the issue to prevent the problem from mistakenly recurring.
Link: https://lkml.kernel.org/r/20240207203134.69976-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
69 lines
1.2 KiB
C
69 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Author: SeongJae Park <sj@kernel.org>
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*/
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#define _GNU_SOURCE
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#include <fcntl.h>
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#include <stdbool.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <sys/time.h>
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#include <unistd.h>
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#define DBGFS_TARGET_IDS "/sys/kernel/debug/damon/target_ids"
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static void write_targetid_exit(void)
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{
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int target_ids_fd = open(DBGFS_TARGET_IDS, O_RDWR);
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char pid_str[128];
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snprintf(pid_str, sizeof(pid_str), "%d", getpid());
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write(target_ids_fd, pid_str, sizeof(pid_str));
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close(target_ids_fd);
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exit(0);
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}
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unsigned long msec_timestamp(void)
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{
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struct timeval tv;
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gettimeofday(&tv, NULL);
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return tv.tv_sec * 1000UL + tv.tv_usec / 1000;
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}
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int main(int argc, char *argv[])
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{
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unsigned long start_ms;
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int time_to_run, nr_forks = 0;
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if (argc != 2) {
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fprintf(stderr, "Usage: %s <msecs to run>\n", argv[0]);
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exit(1);
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}
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time_to_run = atoi(argv[1]);
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start_ms = msec_timestamp();
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while (true) {
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int pid = fork();
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if (pid < 0) {
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fprintf(stderr, "fork() failed\n");
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exit(1);
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}
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if (pid == 0)
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write_targetid_exit();
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wait(NULL);
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nr_forks++;
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if (msec_timestamp() - start_ms > time_to_run)
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break;
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}
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printf("%d\n", nr_forks);
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return 0;
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}
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