From 4dfaa528d451aa7926be4f1b4cf8d0ffe338421d Mon Sep 17 00:00:00 2001 From: Franck Bui Date: Wed, 11 Apr 2018 16:58:49 +0200 Subject: [PATCH] fs-util: introduce fchmod_opath() fchmod(2) still doesn't take file descriptors opened with O_PATH. --- src/basic/fs-util.c | 15 +++++++++++++++ src/basic/fs-util.h | 1 + src/tmpfiles/tmpfiles.c | 10 ++-------- 3 files changed, 18 insertions(+), 8 deletions(-) diff --git a/src/basic/fs-util.c b/src/basic/fs-util.c index 61aeb1fc8a2..13dccfef545 100644 --- a/src/basic/fs-util.c +++ b/src/basic/fs-util.c @@ -241,6 +241,21 @@ int fchmod_umask(int fd, mode_t m) { return r; } +int fchmod_opath(int fd, mode_t m) { + char procfs_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int)]; + + /* This function operates also on fd that might have been opened with + * O_PATH. Indeed fchmodat() doesn't have the AT_EMPTY_PATH flag like + * fchownat() does. */ + + xsprintf(procfs_path, "/proc/self/fd/%i", fd); + + if (chmod(procfs_path, m) < 0) + return -errno; + + return 0; +} + int fd_warn_permissions(const char *path, int fd) { struct stat st; diff --git a/src/basic/fs-util.h b/src/basic/fs-util.h index 2b1d2097fdb..6157fe81bff 100644 --- a/src/basic/fs-util.h +++ b/src/basic/fs-util.h @@ -33,6 +33,7 @@ int readlink_and_make_absolute(const char *p, char **r); int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid); int fchmod_umask(int fd, mode_t mode); +int fchmod_opath(int fd, mode_t m); int fd_warn_permissions(const char *path, int fd); diff --git a/src/tmpfiles/tmpfiles.c b/src/tmpfiles/tmpfiles.c index 5755f22160b..4e437a57fd7 100644 --- a/src/tmpfiles/tmpfiles.c +++ b/src/tmpfiles/tmpfiles.c @@ -808,15 +808,9 @@ static int fd_set_perms(Item *i, int fd, const struct stat *st) { if (m == (st->st_mode & 07777)) log_debug("\"%s\" has correct mode %o already.", path, st->st_mode); else { - char procfs_path[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)]; - log_debug("Changing \"%s\" to mode %o.", path, m); - - /* fchmodat() still doesn't have AT_EMPTY_PATH flag. */ - xsprintf(procfs_path, "/proc/self/fd/%i", fd); - - if (chmod(procfs_path, m) < 0) - return log_error_errno(errno, "chmod() of %s via %s failed: %m", path, procfs_path); + if (fchmod_opath(fd, m) < 0) + return log_error_errno(errno, "fchmod() of %s failed: %m", path); } } }