blob: b54afb867feea43f2a61b0ff617d1dc391185a24 [file] [log] [blame]
Description: CVE-2015-1197
Apply patch by Vitezslav Cizek of SuSE to fix CVE-2015-1197.
Upstream is dormant or no longer existing. To restore the old
behaviour use --extract-over-symlinks (Closes: #774669)
This issue has been discovered by Alexander Cherepanov.
Author: Vitezslav Cizek <vcizek@suse.cz>
Bug-Debian: https://bugs.debian.org/774669
Upstream-Status: Backport
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
--- cpio-2.11+dfsg.orig/doc/cpio.1
+++ cpio-2.11+dfsg/doc/cpio.1
@@ -22,6 +22,7 @@ cpio \- copy files to and from archives
[\-\-owner=[user][:.][group]] [\-\-no-preserve-owner] [\-\-message=message]
[\-\-force\-local] [\-\-no\-absolute\-filenames] [\-\-sparse]
[\-\-only\-verify\-crc] [\-\-to\-stdout] [\-\-quiet] [\-\-rsh-command=command]
+[\-\-extract\-over\-symlinks]
[\-\-help] [\-\-version] [pattern...] [< archive]
.B cpio
--- cpio-2.11+dfsg.orig/src/copyin.c
+++ cpio-2.11+dfsg/src/copyin.c
@@ -700,6 +700,51 @@ copyin_link (struct cpio_file_stat *file
free (link_name);
}
+
+static int
+path_contains_symlink(char *path)
+{
+ struct stat st;
+ char *slash;
+ char *nextslash;
+
+ /* we got NULL pointer or empty string */
+ if (!path || !*path) {
+ return false;
+ }
+
+ slash = path;
+
+ while ((nextslash = strchr(slash + 1, '/')) != NULL) {
+ slash = nextslash;
+ *slash = '\0';
+
+ if (lstat(path, &st) != 0) {
+ if (errno == ELOOP) {
+ /* ELOOP - too many symlinks */
+ *slash = '/';
+ return true;
+ } else if (errno == ENOMEM) {
+ /* No memory for lstat - terminate */
+ xalloc_die();
+ } else {
+ /* cannot lstat path - give up */
+ *slash = '/';
+ return false;
+ }
+ }
+
+ if (S_ISLNK(st.st_mode)) {
+ *slash = '/';
+ return true;
+ }
+
+ *slash = '/';
+ }
+
+ return false;
+}
+
static void
copyin_file (struct cpio_file_stat *file_hdr, int in_file_des)
{
@@ -1471,6 +1516,23 @@ process_copy_in ()
{
/* Copy the input file into the directory structure. */
+ /* Can we write files over symlinks? */
+ if (!extract_over_symlinks)
+ {
+ if (path_contains_symlink(file_hdr.c_name))
+ {
+ /* skip the file */
+ /*
+ fprintf(stderr, "Can't write over symlinks. Skipping %s\n", file_hdr.c_name);
+ tape_toss_input (in_file_des, file_hdr.c_filesize);
+ tape_skip_padding (in_file_des, file_hdr.c_filesize);
+ continue;
+ */
+ /* terminate */
+ error (1, 0, _("Can't write over symlinks: %s\n"), file_hdr.c_name);
+ }
+ }
+
/* Do we need to rename the file? */
if (rename_flag || rename_batch_file)
{
--- cpio-2.11+dfsg.orig/src/extern.h
+++ cpio-2.11+dfsg/src/extern.h
@@ -95,6 +95,7 @@ extern char input_is_special;
extern char output_is_special;
extern char input_is_seekable;
extern char output_is_seekable;
+extern bool extract_over_symlinks;
extern int (*xstat) ();
extern void (*copy_function) ();
--- cpio-2.11+dfsg.orig/src/global.c
+++ cpio-2.11+dfsg/src/global.c
@@ -187,6 +187,9 @@ bool to_stdout_option = false;
/* The name this program was run with. */
char *program_name;
+/* Extract files over symbolic links */
+bool extract_over_symlinks;
+
/* A pointer to either lstat or stat, depending on whether
dereferencing of symlinks is done for input files. */
int (*xstat) ();
--- cpio-2.11+dfsg.orig/src/main.c
+++ cpio-2.11+dfsg/src/main.c
@@ -57,7 +57,8 @@ enum cpio_options {
FORCE_LOCAL_OPTION,
DEBUG_OPTION,
BLOCK_SIZE_OPTION,
- TO_STDOUT_OPTION
+ TO_STDOUT_OPTION,
+ EXTRACT_OVER_SYMLINKS
};
const char *program_authors[] =
@@ -222,6 +223,8 @@ static struct argp_option options[] = {
N_("Create leading directories where needed"), GRID+1 },
{"no-preserve-owner", NO_PRESERVE_OWNER_OPTION, 0, 0,
N_("Do not change the ownership of the files"), GRID+1 },
+ {"extract-over-symlinks", EXTRACT_OVER_SYMLINKS, 0, 0,
+ N_("Force writing over symbolic links"), GRID+1 },
{"unconditional", 'u', NULL, 0,
N_("Replace all files unconditionally"), GRID+1 },
{"sparse", SPARSE_OPTION, NULL, 0,
@@ -412,6 +415,10 @@ crc newc odc bin ustar tar (all-caps als
no_chown_flag = true;
break;
+ case EXTRACT_OVER_SYMLINKS: /* --extract-over-symlinks */
+ extract_over_symlinks = true;
+ break;
+
case 'o': /* Copy-out mode. */
if (copy_function != 0)
error (PAXEXIT_FAILURE, 0, _("Mode already defined"));