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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316/* SPDX-License-Identifier: GPL-2.0 *//* Helpers shared by the binfmt_misc selftests. */#ifndef __SELFTESTS_EXEC_BINFMT_MISC_COMMON_H#define __SELFTESTS_EXEC_BINFMT_MISC_COMMON_H
#include <elf.h>#include <errno.h>#include <fcntl.h>#include <libgen.h>#include <limits.h>#include <link.h>#include <stdbool.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <sys/mount.h>#include <sys/types.h>#include <sys/wait.h>#include <unistd.h>
#define BINFMT_DIR "/proc/sys/fs/binfmt_misc"#define BINFMT_REG BINFMT_DIR "/register"
/* comm holds 15 usable chars; a read of /proc/self/comm appends a newline. */#define TASK_COMM_LEN 16
/* The canonical payload argv: run_payload() passes it, the payloads assert it. */#define PAYLOAD_ARGV0 "payload-argv0"#define PAYLOAD_ARG1 "argone"#define PAYLOAD_ARG2 "argtwo"
/* Marker the loader tests poke into the payload's e_ident padding. */#define LOADER_MARKER "LDRTST"
/* Exit status run_payload() reports when the exec was refused as unhandled. */#define RUN_ENOEXEC 42
static inline int copy_file(const char *src, const char *dst){ char buf[4096]; int in, out; ssize_t n;
in = open(src, O_RDONLY); if (in < 0) return -1; /* The tests share /tmp, so never write through a name they don't own. */ unlink(dst); out = open(dst, O_WRONLY | O_CREAT | O_EXCL, 0755); if (out < 0) { close(in); return -1; } while ((n = read(in, buf, sizeof(buf))) > 0) { if (write(out, buf, n) != n) { close(in); close(out); return -1; } } close(in); close(out); return n < 0 ? -1 : 0;}
/* Write @rule to the register file, preserving the write's errno. */static inline int write_reg(const char *rule){ int fd, saved; ssize_t n;
fd = open(BINFMT_REG, O_WRONLY); if (fd < 0) return -1; n = write(fd, rule, strlen(rule)); saved = errno; close(fd); errno = saved; return n < 0 ? -1 : 0;}
static inline void unregister(const char *name){ char path[PATH_MAX]; int fd;
snprintf(path, sizeof(path), BINFMT_DIR "/%s", name); fd = open(path, O_WRONLY); if (fd >= 0) { if (write(fd, "-1", 2) < 0) ; /* best effort */ close(fd); }}
/* Write @line to @entry's file, reporting the errno it was refused with. */static inline int entry_command(const char *entry, const char *line){ char path[PATH_MAX]; int fd, retval = 0; size_t len = strlen(line);
snprintf(path, sizeof(path), BINFMT_DIR "/%s", entry); fd = open(path, O_WRONLY | O_CLOEXEC); if (fd < 0) return -errno; if (write(fd, line, len) != (ssize_t)len) retval = -errno; close(fd); return retval;}
/* Does @entry's file report @line? */static inline bool entry_shows(const char *entry, const char *line){ char path[PATH_MAX], buf[PATH_MAX]; bool found = false; FILE *fp;
snprintf(path, sizeof(path), BINFMT_DIR "/%s", entry); fp = fopen(path, "r"); if (!fp) return false; while (fgets(buf, sizeof(buf), fp)) { buf[strcspn(buf, "\n")] = '\0'; if (!strcmp(buf, line)) { found = true; break; } } fclose(fp); return found;}
/* Mount binfmt_misc unless it already is, and report whether it is usable. */static inline bool binfmt_misc_available(void){ if (access(BINFMT_REG, F_OK) < 0) mount("binfmt_misc", BINFMT_DIR, "binfmt_misc", 0, NULL); return access(BINFMT_REG, F_OK) == 0;}
/* Absolute path of @name in the directory this test was built into. */static inline int artifact_path(char *out, size_t sz, const char *name){ char exe[PATH_MAX]; ssize_t n;
n = readlink("/proc/self/exe", exe, sizeof(exe) - 1); if (n < 0) return -1; exe[n] = '\0'; if ((size_t)snprintf(out, sz, "%s/%s", dirname(exe), name) >= sz) return -1; return 0;}
/* Probe kernel support for a registration flag with a throwaway entry. */static inline bool binfmt_flag_supported(char flag){ char rule[64];
snprintf(rule, sizeof(rule), ":bm_flag_probe:E::bmprobe::/bin/true:%c", flag); if (write_reg(rule)) return false; unregister("bm_flag_probe"); return true;}
/* * Run @path with the canonical payload argv and return its exit status, or * RUN_ENOEXEC when the exec itself was refused as unhandled. */static inline int run_payload(const char *path){ int status; pid_t pid;
pid = fork(); if (pid == 0) { execl(path, PAYLOAD_ARGV0, PAYLOAD_ARG1, PAYLOAD_ARG2, (char *)NULL); _exit(errno == ENOEXEC ? RUN_ENOEXEC : 126); } if (pid < 0 || waitpid(pid, &status, 0) != pid || !WIFEXITED(status)) return -1; return WEXITSTATUS(status);}
/* Does the exe link name @path? */static inline bool exe_is(const char *path){ char exe[PATH_MAX], real[PATH_MAX]; ssize_t n;
n = readlink("/proc/self/exe", exe, sizeof(exe) - 1); if (n <= 0 || !realpath(path, real)) return false; exe[n] = '\0'; return !strcmp(exe, real);}
/* Is comm @name truncated to what a comm can hold? */static inline bool comm_is(const char *name){ char comm[TASK_COMM_LEN + 2], expect[TASK_COMM_LEN]; ssize_t n; int fd;
fd = open("/proc/self/comm", O_RDONLY); if (fd < 0) return false; n = read(fd, comm, sizeof(comm) - 1); close(fd); if (n <= 0) return false; if (comm[n - 1] == '\n') n--; comm[n] = '\0'; snprintf(expect, sizeof(expect), "%s", name); return !strcmp(comm, expect);}
/* Opening @path for writing has to fail with ETXTBSY. */static inline bool write_denied(const char *path){ int fd = open(path, O_WRONLY);
if (fd >= 0) { close(fd); return false; } return errno == ETXTBSY;}
static inline int patch_file(const char *path, off_t off, const void *data, size_t len){ ssize_t n; int fd;
fd = open(path, O_WRONLY); if (fd < 0) return -1; n = pwrite(fd, data, len, off); close(fd); return n == (ssize_t)len ? 0 : -1;}
/* start_code and end_code are the 26th and 27th fields of /proc/pid/stat. */static inline int stat_codes(pid_t pid, unsigned long *start_code, unsigned long *end_code){ char buf[4096], path[64], *p; ssize_t n; int fd, i;
snprintf(path, sizeof(path), "/proc/%d/stat", pid); fd = open(path, O_RDONLY); if (fd < 0) return -1; n = read(fd, buf, sizeof(buf) - 1); close(fd); if (n <= 0) return -1; buf[n] = '\0';
/* Skip "pid (comm)", then start_code is the 24th field after it. */ p = strrchr(buf, ')'); if (!p) return -1; p++; for (i = 0; i < 23; i++) { p = strchr(p + 1, ' '); if (!p) return -1; } if (sscanf(p, " %lu %lu", start_code, end_code) != 2) return -1; return 0;}
/* Find the system loader through our own PT_INTERP. */static inline int find_loader(char *out, size_t sz){ ElfW(Ehdr) eh; ElfW(Phdr) ph; int fd, i, ret = -1;
fd = open("/proc/self/exe", O_RDONLY); if (fd < 0) return -1; if (pread(fd, &eh, sizeof(eh), 0) != sizeof(eh)) goto out; for (i = 0; i < eh.e_phnum; i++) { if (pread(fd, &ph, sizeof(ph), eh.e_phoff + i * eh.e_phentsize) != sizeof(ph)) goto out; if (ph.p_type != PT_INTERP) continue; if (!ph.p_filesz || ph.p_filesz > sz) goto out; if (pread(fd, out, ph.p_filesz, ph.p_offset) != (ssize_t)ph.p_filesz) goto out; out[ph.p_filesz - 1] = '\0'; ret = 0; break; }out: close(fd); return ret;}
#endif /* __SELFTESTS_EXEC_BINFMT_MISC_COMMON_H */