File cpio-2.12-out_of_bounds_write.patch of Package cpio.20871
* src/copyin.c (process_copy_in): Make sure that file_hdr.c_name
has at least two bytes allocated.
* src/util.c (cpio_safer_name_suffix): Document that use of this
function requires to be careful.
---
src/copyin.c | 2 ++
src/util.c | 5 ++++-
2 files changed, 6 insertions(+), 1 deletion(-)
Index: cpio-2.12/src/copyin.c
===================================================================
--- cpio-2.12.orig/src/copyin.c
+++ cpio-2.12/src/copyin.c
@@ -1433,6 +1433,18 @@ process_copy_in ()
break;
}
+ /* Fix for CVE-2016-2037 (bsc#963448) and resultant regression (bsc#1028410).
+ For tar and ustar archive formats, file_hdr.c_namesize is not defined and
+ file_hdr.c_name uses static memory. Therefore we can't rely on
+ file_hdr.c_namesize and we can't realloc memory for these archive types.
+ However the patch is still correct for CVE-2016-2037 (we have to be sure
+ that the allocated NAME buffer has a capacity at least 2 bytes to allow
+ us to store the "." string inside) as static char array for tar and ustar
+ has size 2 at least (see tar.c:stash_tar_filename()).
+ */
+ if (archive_format != arf_tar && archive_format != arf_ustar
+ && file_hdr.c_namesize <= 1)
+ file_hdr.c_name = xrealloc(file_hdr.c_name, 2);
cpio_safer_name_suffix (file_hdr.c_name, false, !no_abs_paths_flag,
false);
Index: cpio-2.12/src/util.c
===================================================================
--- cpio-2.12.orig/src/util.c
+++ cpio-2.12/src/util.c
@@ -1460,7 +1460,10 @@ set_file_times (int fd,
}
/* Do we have to ignore absolute paths, and if so, does the filename
- have an absolute path? */
+ have an absolute path?
+ Before calling this function make sure that the allocated NAME buffer has
+ capacity at least 2 bytes to allow us to store the "." string inside. */
+
void
cpio_safer_name_suffix (char *name, bool link_target, bool absolute_names,
bool strip_leading_dots)
