e99dd67ad8
* gnu/packages/compression.scm (libtar)[source]: Add patch.
* gnu/packages/patches/libtar-CVE-2013-4420.patch: New variable.
* gnu/local.mk (dist_patch_DATA): Add it.
This is a follow-up to 89d80159b1.
119 lines
2.9 KiB
Diff
119 lines
2.9 KiB
Diff
Author: Raphael Geissert <geissert@debian.org>
|
|
Bug-Debian: https://bugs.debian.org/731860
|
|
Description: Avoid directory traversal when extracting archives
|
|
by skipping over leading slashes and any prefix containing ".." components.
|
|
Forwarded: yes
|
|
|
|
--- a/lib/decode.c
|
|
+++ b/lib/decode.c
|
|
@@ -22,6 +22,36 @@
|
|
#endif
|
|
|
|
|
|
+char *
|
|
+safer_name_suffix (char const *file_name)
|
|
+{
|
|
+ char const *p, *t;
|
|
+ p = t = file_name;
|
|
+ while (*p == '/') t = ++p;
|
|
+ while (*p)
|
|
+ {
|
|
+ while (p[0] == '.' && p[0] == p[1] && p[2] == '/')
|
|
+ {
|
|
+ p += 3;
|
|
+ t = p;
|
|
+ }
|
|
+ /* advance pointer past the next slash */
|
|
+ while (*p && (p++)[0] != '/');
|
|
+ }
|
|
+
|
|
+ if (!*t)
|
|
+ {
|
|
+ t = ".";
|
|
+ }
|
|
+
|
|
+ if (t != file_name)
|
|
+ {
|
|
+ /* TODO: warn somehow that the path was modified */
|
|
+ }
|
|
+ return (char*)t;
|
|
+}
|
|
+
|
|
+
|
|
/* determine full path name */
|
|
char *
|
|
th_get_pathname(TAR *t)
|
|
@@ -29,17 +59,17 @@ th_get_pathname(TAR *t)
|
|
static char filename[MAXPATHLEN];
|
|
|
|
if (t->th_buf.gnu_longname)
|
|
- return t->th_buf.gnu_longname;
|
|
+ return safer_name_suffix(t->th_buf.gnu_longname);
|
|
|
|
if (t->th_buf.prefix[0] != '\0')
|
|
{
|
|
snprintf(filename, sizeof(filename), "%.155s/%.100s",
|
|
t->th_buf.prefix, t->th_buf.name);
|
|
- return filename;
|
|
+ return safer_name_suffix(filename);
|
|
}
|
|
|
|
snprintf(filename, sizeof(filename), "%.100s", t->th_buf.name);
|
|
- return filename;
|
|
+ return safer_name_suffix(filename);
|
|
}
|
|
|
|
|
|
--- a/lib/extract.c
|
|
+++ b/lib/extract.c
|
|
@@ -298,14 +298,14 @@ tar_extract_hardlink(TAR * t, char *real
|
|
if (mkdirhier(dirname(filename)) == -1)
|
|
return -1;
|
|
libtar_hashptr_reset(&hp);
|
|
- if (libtar_hash_getkey(t->h, &hp, th_get_linkname(t),
|
|
+ if (libtar_hash_getkey(t->h, &hp, safer_name_suffix(th_get_linkname(t)),
|
|
(libtar_matchfunc_t)libtar_str_match) != 0)
|
|
{
|
|
lnp = (char *)libtar_hashptr_data(&hp);
|
|
linktgt = &lnp[strlen(lnp) + 1];
|
|
}
|
|
else
|
|
- linktgt = th_get_linkname(t);
|
|
+ linktgt = safer_name_suffix(th_get_linkname(t));
|
|
|
|
#ifdef DEBUG
|
|
printf(" ==> extracting: %s (link to %s)\n", filename, linktgt);
|
|
@@ -343,9 +343,9 @@ tar_extract_symlink(TAR *t, char *realna
|
|
|
|
#ifdef DEBUG
|
|
printf(" ==> extracting: %s (symlink to %s)\n",
|
|
- filename, th_get_linkname(t));
|
|
+ filename, safer_name_suffix(th_get_linkname(t)));
|
|
#endif
|
|
- if (symlink(th_get_linkname(t), filename) == -1)
|
|
+ if (symlink(safer_name_suffix(th_get_linkname(t)), filename) == -1)
|
|
{
|
|
#ifdef DEBUG
|
|
perror("symlink()");
|
|
--- a/lib/internal.h
|
|
+++ b/lib/internal.h
|
|
@@ -15,3 +15,4 @@
|
|
|
|
#include <libtar.h>
|
|
|
|
+char* safer_name_suffix(char const*);
|
|
--- a/lib/output.c
|
|
+++ b/lib/output.c
|
|
@@ -123,9 +123,9 @@ th_print_long_ls(TAR *t)
|
|
else
|
|
printf(" link to ");
|
|
if ((t->options & TAR_GNU) && t->th_buf.gnu_longlink != NULL)
|
|
- printf("%s", t->th_buf.gnu_longlink);
|
|
+ printf("%s", safer_name_suffix(t->th_buf.gnu_longlink));
|
|
else
|
|
- printf("%.100s", t->th_buf.linkname);
|
|
+ printf("%.100s", safer_name_suffix(t->th_buf.linkname));
|
|
}
|
|
|
|
putchar('\n');
|