From e3133e4db70476fb7adfdedb738483e2255ce0e1 Mon Sep 17 00:00:00 2001 From: Stanislav Malyshev Date: Sat, 2 Mar 2019 23:42:53 -0800 Subject: [PATCH] Fix bug #77630 - safer rename() procedure In order to rename safer, we do the following: - set umask to 077 (unfortunately, not TS, so excluding ZTS) - chown() first, to set proper group before allowing group access - chmod() after, even if chown() fails --- main/streams/plain_wrapper.c | 51 ++++++++++++++++++++++++------------ 1 file changed, 34 insertions(+), 17 deletions(-) diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c index af890a9aa3bb..7fdf906e6fad 100644 --- a/main/streams/plain_wrapper.c +++ b/main/streams/plain_wrapper.c @@ -1160,34 +1160,51 @@ static int php_plain_files_rename(php_stream_wrapper *wrapper, const char *url_f # ifdef EXDEV if (errno == EXDEV) { zend_stat_t sb; +# if !defined(ZTS) && !defined(TSRM_WIN32) && !defined(NETWARE) + /* not sure what to do in ZTS case, umask is not thread-safe */ + int oldmask = umask(077); +# endif + int success = 0; if (php_copy_file(url_from, url_to) == SUCCESS) { if (VCWD_STAT(url_from, &sb) == 0) { + success = 1; # if !defined(TSRM_WIN32) && !defined(NETWARE) - if (VCWD_CHMOD(url_to, sb.st_mode)) { - if (errno == EPERM) { - php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); - VCWD_UNLINK(url_from); - return 1; - } + /* + * Try to set user and permission info on the target. + * If we're not root, then some of these may fail. + * We try chown first, to set proper group info, relying + * on the system environment to have proper umask to not allow + * access to the file in the meantime. + */ + if (VCWD_CHOWN(url_to, sb.st_uid, sb.st_gid)) { php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); - return 0; + if (errno != EPERM) { + success = 0; + } } - if (VCWD_CHOWN(url_to, sb.st_uid, sb.st_gid)) { - if (errno == EPERM) { + + if (success) { + if (VCWD_CHMOD(url_to, sb.st_mode)) { php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); - VCWD_UNLINK(url_from); - return 1; + if (errno != EPERM) { + success = 0; + } } - php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); - return 0; } # endif - VCWD_UNLINK(url_from); - return 1; + if (success) { + VCWD_UNLINK(url_from); + } + } else { + php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); } + } else { + php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); } - php_error_docref2(NULL, url_from, url_to, E_WARNING, "%s", strerror(errno)); - return 0; +# if !defined(ZTS) && !defined(TSRM_WIN32) && !defined(NETWARE) + umask(oldmask); +# endif + return success; } # endif #endif