From 4402e6048fb2a56461f9e4d474fc2f1391248781 Mon Sep 17 00:00:00 2001 From: "Richard W.M. Jones" Date: Sat, 15 Jan 2011 13:18:36 +0000 Subject: [PATCH] inspect: Add macros for file size limits. This also bumps the file size limit for "small text files" up to 2 MB, since we want to parse Windows CD txtsetup.sif files that are usually around 500K in size. --- src/inspect.c | 46 +++++++++++++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 9 deletions(-) diff --git a/src/inspect.c b/src/inspect.c index 46c7fe4..50c4e72 100644 --- a/src/inspect.c +++ b/src/inspect.c @@ -45,6 +45,31 @@ #if defined(HAVE_PCRE) && defined(HAVE_HIVEX) +/* Some limits on what we will read, for safety. */ + +/* Small text configuration files. + * + * The upper limit is for general files that we grep or download. The + * largest such file is probably "txtsetup.sif" from Windows CDs + * (~500K). This number has to be larger than any legitimate file and + * smaller than the protocol message size. + * + * The lower limit is for files parsed by Augeas on the daemon side, + * where Augeas is running in reduced memory and can potentially + * create a lot of metadata so we really need to be careful about + * those. + */ +#define MAX_SMALL_FILE_SIZE (2 * 1000 * 1000) +#define MAX_AUGEAS_FILE_SIZE (100 * 1000) + +/* Maximum Windows Registry hive that we will download to /tmp. Some + * registries can be legitimately very large. + */ +#define MAX_REGISTRY_SIZE (100 * 1000 * 1000) + +/* Maximum RPM or dpkg database we will download to /tmp. */ +#define MAX_PKG_DB_SIZE (10 * 1000 * 1000) + /* Compile all the regular expressions once when the shared library is * loaded. PCRE is thread safe so we're supposedly OK here if * multiple threads call into the libguestfs API functions below @@ -417,7 +442,7 @@ parse_lsb_release (guestfs_h *g, struct inspect_fs *fs) if (size == -1) /* guestfs_filesize failed and has already set error in handle */ return -1; - if (size > 1000000) { + if (size > MAX_SMALL_FILE_SIZE) { error (g, _("size of %s is unreasonably large (%" PRIi64 " bytes)"), filename, size); return -1; @@ -753,7 +778,7 @@ check_hostname_freebsd (guestfs_h *g, struct inspect_fs *fs) if (size == -1) /* guestfs_filesize failed and has already set error in handle */ return -1; - if (size > 1000000) { + if (size > MAX_SMALL_FILE_SIZE) { error (g, _("size of %s is unreasonably large (%" PRIi64 " bytes)"), filename, size); return -1; @@ -1076,7 +1101,8 @@ check_windows_software_registry (guestfs_h *g, struct inspect_fs *fs) hive_h *h = NULL; hive_value_h *values = NULL; - if (download_to_tmp (g, software_path, software_local, 100000000) == -1) + if (download_to_tmp (g, software_path, software_local, + MAX_REGISTRY_SIZE) == -1) goto out; h = hivex_open (software_local, g->verbose ? HIVEX_OPEN_VERBOSE : 0); @@ -1184,7 +1210,7 @@ check_windows_system_registry (guestfs_h *g, struct inspect_fs *fs) hive_h *h = NULL; hive_value_h *values = NULL; - if (download_to_tmp (g, system_path, system_local, 100000000) == -1) + if (download_to_tmp (g, system_path, system_local, MAX_REGISTRY_SIZE) == -1) goto out; h = hivex_open (system_local, g->verbose ? HIVEX_OPEN_VERBOSE : 0); @@ -1735,7 +1761,7 @@ list_applications_rpm (guestfs_h *g, struct inspect_fs *fs) { TMP_TEMPLATE_ON_STACK (tmpfile); - if (download_to_tmp (g, "/var/lib/rpm/Name", tmpfile, 10000000) == -1) + if (download_to_tmp (g, "/var/lib/rpm/Name", tmpfile, MAX_PKG_DB_SIZE) == -1) return NULL; struct guestfs_application_list *apps = NULL, *ret = NULL; @@ -1837,7 +1863,8 @@ list_applications_deb (guestfs_h *g, struct inspect_fs *fs) { TMP_TEMPLATE_ON_STACK (tmpfile); - if (download_to_tmp (g, "/var/lib/dpkg/status", tmpfile, 10000000) == -1) + if (download_to_tmp (g, "/var/lib/dpkg/status", tmpfile, + MAX_PKG_DB_SIZE) == -1) return NULL; struct guestfs_application_list *apps = NULL, *ret = NULL; @@ -1949,7 +1976,8 @@ list_applications_windows (guestfs_h *g, struct inspect_fs *fs) hive_h *h = NULL; hive_node_h *children = NULL; - if (download_to_tmp (g, software_path, software_local, 100000000) == -1) + if (download_to_tmp (g, software_path, software_local, + MAX_REGISTRY_SIZE) == -1) goto out; h = hivex_open (software_local, g->verbose ? HIVEX_OPEN_VERBOSE : 0); @@ -2168,7 +2196,7 @@ inspect_with_augeas (guestfs_h *g, struct inspect_fs *fs, const char *filename, if (size == -1) /* guestfs_filesize failed and has already set error in handle */ return -1; - if (size > 100000) { + if (size > MAX_AUGEAS_FILE_SIZE) { error (g, _("size of %s is unreasonably large (%" PRIi64 " bytes)"), filename, size); return -1; @@ -2218,7 +2246,7 @@ first_line_of_file (guestfs_h *g, const char *filename) if (size == -1) /* guestfs_filesize failed and has already set error in handle */ return NULL; - if (size > 1000000) { + if (size > MAX_SMALL_FILE_SIZE) { error (g, _("size of %s is unreasonably large (%" PRIi64 " bytes)"), filename, size); return NULL; -- 1.8.3.1