diff options
-rw-r--r-- | src/basic/fileio.c | 124 | ||||
-rw-r--r-- | src/basic/fileio.h | 6 | ||||
-rw-r--r-- | src/core/manager.c | 2 | ||||
-rw-r--r-- | src/coredump/coredump.c | 54 | ||||
-rw-r--r-- | src/journal-remote/journal-gatewayd.c | 4 | ||||
-rw-r--r-- | src/journal/journal-send.c | 2 | ||||
-rw-r--r-- | src/journal/journal-verify.c | 6 | ||||
-rw-r--r-- | src/test/test-tmpfiles.c | 26 |
8 files changed, 146 insertions, 78 deletions
diff --git a/src/basic/fileio.c b/src/basic/fileio.c index 69590941e5..2a9b6e46ad 100644 --- a/src/basic/fileio.c +++ b/src/basic/fileio.c @@ -1083,30 +1083,6 @@ int mkostemp_safe(char *pattern, int flags) { return fd; } -int open_tmpfile(const char *path, int flags) { - char *p; - int fd; - - assert(path); - -#ifdef O_TMPFILE - /* Try O_TMPFILE first, if it is supported */ - fd = open(path, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR); - if (fd >= 0) - return fd; -#endif - - /* Fall back to unguessable name + unlinking */ - p = strjoina(path, "/systemd-tmp-XXXXXX"); - - fd = mkostemp_safe(p, flags); - if (fd < 0) - return fd; - - unlink(p); - return fd; -} - int tempfn_xxxxxx(const char *p, const char *extra, char **ret) { const char *fn; char *t; @@ -1278,3 +1254,103 @@ int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space) return fputs(s, f); } + +int open_tmpfile_unlinkable(const char *directory, int flags) { + char *p; + int fd; + + assert(directory); + + /* Returns an unlinked temporary file that cannot be linked into the file system anymore */ + +#ifdef O_TMPFILE + /* Try O_TMPFILE first, if it is supported */ + fd = open(directory, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR); + if (fd >= 0) + return fd; +#endif + + /* Fall back to unguessable name + unlinking */ + p = strjoina(directory, "/systemd-tmp-XXXXXX"); + + fd = mkostemp_safe(p, flags); + if (fd < 0) + return fd; + + (void) unlink(p); + + return fd; +} + +int open_tmpfile_linkable(const char *target, int flags, char **ret_path) { + _cleanup_free_ char *tmp = NULL; + int r, fd; + + assert(target); + assert(ret_path); + + /* Don't allow O_EXCL, as that has a special meaning for O_TMPFILE */ + assert((flags & O_EXCL) == 0); + + /* Creates a temporary file, that shall be renamed to "target" later. If possible, this uses O_TMPFILE – in + * which case "ret_path" will be returned as NULL. If not possible a the tempoary path name used is returned in + * "ret_path". Use link_tmpfile() below to rename the result after writing the file in full. */ + +#ifdef O_TMPFILE + { + _cleanup_free_ char *dn = NULL; + + dn = dirname_malloc(target); + if (!dn) + return -ENOMEM; + + fd = open(dn, O_TMPFILE|flags, 0640); + if (fd >= 0) { + *ret_path = NULL; + return fd; + } + + log_debug_errno(errno, "Failed to use O_TMPFILE on %s: %m", dn); + } +#endif + + r = tempfn_random(target, NULL, &tmp); + if (r < 0) + return r; + + fd = open(tmp, O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY|flags, 0640); + if (fd < 0) + return -errno; + + *ret_path = tmp; + tmp = NULL; + + return fd; +} + +int link_tmpfile(int fd, const char *path, const char *target) { + + assert(fd >= 0); + assert(target); + + /* Moves a temporary file created with open_tmpfile() above into its final place. if "path" is NULL an fd + * created with O_TMPFILE is assumed, and linkat() is used. Otherwise it is assumed O_TMPFILE is not supported + * on the directory, and renameat2() is used instead. + * + * Note that in both cases we will not replace existing files. This is because linkat() dos not support this + * operation currently (renameat2() does), and there is no nice way to emulate this. */ + + if (path) { + if (rename_noreplace(AT_FDCWD, path, AT_FDCWD, target) < 0) + return -errno; + } else { + char proc_fd_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(fd) + 1]; + + xsprintf(proc_fd_path, "/proc/self/fd/%i", fd); + + if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0) + return -errno; + } + + return 0; +} diff --git a/src/basic/fileio.h b/src/basic/fileio.h index 8084895ff3..58dbc80c24 100644 --- a/src/basic/fileio.h +++ b/src/basic/fileio.h @@ -72,7 +72,6 @@ int fflush_and_check(FILE *f); int fopen_temporary(const char *path, FILE **_f, char **_temp_path); int mkostemp_safe(char *pattern, int flags); -int open_tmpfile(const char *path, int flags); int tempfn_xxxxxx(const char *p, const char *extra, char **ret); int tempfn_random(const char *p, const char *extra, char **ret); @@ -82,3 +81,8 @@ int write_timestamp_file_atomic(const char *fn, usec_t n); int read_timestamp_file(const char *fn, usec_t *ret); int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space); + +int open_tmpfile_unlinkable(const char *directory, int flags); +int open_tmpfile_linkable(const char *target, int flags, char **ret_path); + +int link_tmpfile(int fd, const char *path, const char *target); diff --git a/src/core/manager.c b/src/core/manager.c index 5601770670..bd00c224f4 100644 --- a/src/core/manager.c +++ b/src/core/manager.c @@ -2191,7 +2191,7 @@ int manager_open_serialization(Manager *m, FILE **_f) { assert(_f); path = MANAGER_IS_SYSTEM(m) ? "/run/systemd" : "/tmp"; - fd = open_tmpfile(path, O_RDWR|O_CLOEXEC); + fd = open_tmpfile_unlinkable(path, O_RDWR|O_CLOEXEC); if (fd < 0) return -errno; diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c index 2bbb958861..41fc1993d5 100644 --- a/src/coredump/coredump.c +++ b/src/coredump/coredump.c @@ -224,6 +224,8 @@ static int fix_permissions( const char *context[_CONTEXT_MAX], uid_t uid) { + int r; + assert(fd >= 0); assert(target); assert(context); @@ -236,18 +238,9 @@ static int fix_permissions( if (fsync(fd) < 0) return log_error_errno(errno, "Failed to sync coredump %s: %m", coredump_tmpfile_name(filename)); - if (filename) { - if (rename(filename, target) < 0) - return log_error_errno(errno, "Failed to rename coredump %s -> %s: %m", filename, target); - } else { - _cleanup_free_ char *proc_fd_path = NULL; - - if (asprintf(&proc_fd_path, "/proc/self/fd/%d", fd) < 0) - return log_oom(); - - if (linkat(AT_FDCWD, proc_fd_path, AT_FDCWD, target, AT_SYMLINK_FOLLOW) < 0) - return log_error_errno(errno, "Failed to create coredump %s: %m", target); - } + r = link_tmpfile(fd, filename, target); + if (r < 0) + return log_error_errno(r, "Failed to move coredump %s into place: %m", target); return 0; } @@ -308,33 +301,6 @@ static int make_filename(const char *context[_CONTEXT_MAX], char **ret) { return 0; } -static int open_coredump_tmpfile(const char *target, char **ret_filename) { - _cleanup_free_ char *tmp = NULL; - int fd; - int r; - - assert(target); - assert(ret_filename); - - fd = open("/var/lib/systemd/coredump", O_TMPFILE|O_CLOEXEC|O_NOCTTY|O_RDWR, 0640); - if (fd < 0) { - log_debug_errno(errno, "Failed to use O_TMPFILE: %m"); - - r = tempfn_random(target, NULL, &tmp); - if (r < 0) - return log_error_errno(r, "Failed to determine temporary file name: %m"); - - fd = open(tmp, O_CREAT|O_EXCL|O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0640); - if (fd < 0) - return log_error_errno(errno, "Failed to create coredump file %s: %m", tmp); - } - - *ret_filename = tmp; - tmp = NULL; - - return fd; -} - static int save_external_coredump( const char *context[_CONTEXT_MAX], int input_fd, @@ -378,9 +344,9 @@ static int save_external_coredump( mkdir_p_label("/var/lib/systemd/coredump", 0755); - fd = open_coredump_tmpfile(fn, &tmp); + fd = open_tmpfile_linkable(fn, O_RDWR|O_CLOEXEC, &tmp); if (fd < 0) - return fd; + return log_error_errno(fd, "Failed to create temporary file for coredump %s: %m", fn); r = copy_bytes(input_fd, fd, max_size, false); if (r == -EFBIG) { @@ -418,9 +384,11 @@ static int save_external_coredump( goto uncompressed; } - fd_compressed = open_coredump_tmpfile(fn_compressed, &tmp_compressed); - if (fd_compressed < 0) + fd_compressed = open_tmpfile_linkable(fn_compressed, O_RDWR|O_CLOEXEC, &tmp_compressed); + if (fd_compressed < 0) { + log_error_errno(fd_compressed, "Failed to create temporary file for coredump %s: %m", fn_compressed); goto uncompressed; + } r = compress_stream(fd, fd_compressed, -1); if (r < 0) { diff --git a/src/journal-remote/journal-gatewayd.c b/src/journal-remote/journal-gatewayd.c index 60d897758b..4ad9184993 100644 --- a/src/journal-remote/journal-gatewayd.c +++ b/src/journal-remote/journal-gatewayd.c @@ -122,12 +122,14 @@ static int open_journal(RequestMeta *m) { } static int request_meta_ensure_tmp(RequestMeta *m) { + assert(m); + if (m->tmp) rewind(m->tmp); else { int fd; - fd = open_tmpfile("/tmp", O_RDWR|O_CLOEXEC); + fd = open_tmpfile_unlinkable("/tmp", O_RDWR|O_CLOEXEC); if (fd < 0) return fd; diff --git a/src/journal/journal-send.c b/src/journal/journal-send.c index a79846146a..f0959b6237 100644 --- a/src/journal/journal-send.c +++ b/src/journal/journal-send.c @@ -316,7 +316,7 @@ _public_ int sd_journal_sendv(const struct iovec *iov, int n) { buffer_fd = memfd_new(NULL); if (buffer_fd < 0) { if (buffer_fd == -ENOSYS) { - buffer_fd = open_tmpfile("/dev/shm", O_RDWR | O_CLOEXEC); + buffer_fd = open_tmpfile_unlinkable("/dev/shm", O_RDWR | O_CLOEXEC); if (buffer_fd < 0) return buffer_fd; diff --git a/src/journal/journal-verify.c b/src/journal/journal-verify.c index a1241c9bcf..26572ddd76 100644 --- a/src/journal/journal-verify.c +++ b/src/journal/journal-verify.c @@ -838,19 +838,19 @@ int journal_file_verify( } else if (f->seal) return -ENOKEY; - data_fd = open_tmpfile("/var/tmp", O_RDWR | O_CLOEXEC); + data_fd = open_tmpfile_unlinkable("/var/tmp", O_RDWR | O_CLOEXEC); if (data_fd < 0) { r = log_error_errno(data_fd, "Failed to create data file: %m"); goto fail; } - entry_fd = open_tmpfile("/var/tmp", O_RDWR | O_CLOEXEC); + entry_fd = open_tmpfile_unlinkable("/var/tmp", O_RDWR | O_CLOEXEC); if (entry_fd < 0) { r = log_error_errno(entry_fd, "Failed to create entry file: %m"); goto fail; } - entry_array_fd = open_tmpfile("/var/tmp", O_RDWR | O_CLOEXEC); + entry_array_fd = open_tmpfile_unlinkable("/var/tmp", O_RDWR | O_CLOEXEC); if (entry_array_fd < 0) { r = log_error_errno(entry_array_fd, "Failed to create entry array file: %m"); diff --git a/src/test/test-tmpfiles.c b/src/test/test-tmpfiles.c index d7223dd2bf..8fda0904f3 100644 --- a/src/test/test-tmpfiles.c +++ b/src/test/test-tmpfiles.c @@ -32,15 +32,17 @@ #include "util.h" int main(int argc, char** argv) { + _cleanup_free_ char *cmd = NULL, *cmd2 = NULL, *ans = NULL, *ans2 = NULL, *d = NULL, *tmp = NULL, *line = NULL; + _cleanup_close_ int fd = -1, fd2 = -1, fd3 = -1; const char *p = argv[1] ?: "/tmp"; - char *pattern = strjoina(p, "/systemd-test-XXXXXX"); - _cleanup_close_ int fd, fd2; - _cleanup_free_ char *cmd, *cmd2, *ans, *ans2; + char *pattern; log_set_max_level(LOG_DEBUG); log_parse_environment(); - fd = open_tmpfile(p, O_RDWR|O_CLOEXEC); + pattern = strjoina(p, "/systemd-test-XXXXXX"); + + fd = open_tmpfile_unlinkable(p, O_RDWR|O_CLOEXEC); assert_se(fd >= 0); assert_se(asprintf(&cmd, "ls -l /proc/"PID_FMT"/fd/%d", getpid(), fd) > 0); @@ -59,5 +61,21 @@ int main(int argc, char** argv) { log_debug("link2: %s", ans2); assert_se(endswith(ans2, " (deleted)")); + pattern = strjoina(p, "/tmpfiles-test"); + assert_se(tempfn_random(pattern, NULL, &d) >= 0); + + fd = open_tmpfile_linkable(d, O_RDWR|O_CLOEXEC, &tmp); + assert_se(fd >= 0); + assert_se(write(fd, "foobar\n", 7) == 7); + + assert_se(touch(d) >= 0); + assert_se(link_tmpfile(fd, tmp, d) == -EEXIST); + assert_se(unlink(d) >= 0); + assert_se(link_tmpfile(fd, tmp, d) >= 0); + + assert_se(read_one_line_file(d, &line) >= 0); + assert_se(streq(line, "foobar")); + assert_se(unlink(d) >= 0); + return 0; } |