Subject: [PATCH] gnu: ncurses: Fix CVE-2017-10684 and CVE-2017-10685.

From: Leo Famulari <[email-masked]>
Date: Sat, 8 Jul 2017 11:12:25 -0400

* gnu/packages/patches/ncurses-CVE-2017-10684-10685.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/ncurses.scm (ncurses)[replacement]: New field.
(ncurses/fixed): New variable.
---
 gnu/local.mk                                       |   1 +
 gnu/packages/ncurses.scm                           |  14 +-
 .../patches/ncurses-CVE-2017-10684-10685.patch     | 200 +++++++++++++++++++++
 3 files changed, 214 insertions(+), 1 deletion(-)
 create mode 100644 gnu/packages/patches/ncurses-CVE-2017-10684-10685.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index 1bcd790f2..67d655212 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -844,6 +844,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/mupen64plus-ui-console-notice.patch	\
   %D%/packages/patches/musl-CVE-2016-8859.patch			\
   %D%/packages/patches/mutt-store-references.patch		\
+  %D%/packages/patches/ncurses-CVE-2017-10684-10685.patch	\
   %D%/packages/patches/net-tools-bitrot.patch			\
   %D%/packages/patches/netcdf-date-time.patch			\
   %D%/packages/patches/netcdf-tst_h_par.patch			\
diff --git a/gnu/packages/ncurses.scm b/gnu/packages/ncurses.scm
index 44a79e718..0b23baf12 100644
--- a/gnu/packages/ncurses.scm
+++ b/gnu/packages/ncurses.scm
@@ -1,7 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2012, 2013, 2014, 2015 Ludovic Courtès <[email-masked]>
 ;;; Copyright © 2014, 2016 Mark H Weaver <[email-masked]>
-;;; Copyright © 2015 Leo Famulari <[email-masked]>
+;;; Copyright © 2015, 2017 Leo Famulari <[email-masked]>
 ;;; Copyright © 2016 ng0 <[email-masked]>
 ;;; Copyright © 2016 Efraim Flashner <[email-masked]>
 ;;; Copyright © 2016 Jan Nieuwenhuizen <[email-masked]>
@@ -37,6 +37,7 @@
 (define-public ncurses
   (package
     (name "ncurses")
+    (replacement ncurses/fixed)
     (version "6.0")
     (source (origin
               (method url-fetch)
@@ -188,6 +189,17 @@ ncursesw library provides wide character support.")
     (license x11)
     (home-page "https://www.gnu.org/software/ncurses/")))
 
+(define ncurses/fixed
+  (package
+    (inherit ncurses)
+    (source
+      (origin
+        (inherit (package-source ncurses))
+        (patches
+          (append
+            (origin-patches (package-source ncurses))
+            (search-patches "ncurses-CVE-2017-10684-10685.patch")))))))
+
 (define-public dialog
   (package
     (name "dialog")
diff --git a/gnu/packages/patches/ncurses-CVE-2017-10684-10685.patch b/gnu/packages/patches/ncurses-CVE-2017-10684-10685.patch
new file mode 100644
index 000000000..1f1b26801
--- /dev/null
+++ b/gnu/packages/patches/ncurses-CVE-2017-10684-10685.patch
@@ -0,0 +1,200 @@
+Fix CVE-2017-10684 and CVE-2017-10685:
+
+http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-10684
+http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-10685
+
+Bug reports included proof of concept reproducer inputs:
+
+https://bugzilla.redhat.com/show_bug.cgi?id=1464684
+https://bugzilla.redhat.com/show_bug.cgi?id=1464685
+https://bugzilla.redhat.com/show_bug.cgi?id=1464686
+https://bugzilla.redhat.com/show_bug.cgi?id=1464687
+https://bugzilla.redhat.com/show_bug.cgi?id=1464688
+https://bugzilla.redhat.com/show_bug.cgi?id=1464691
+https://bugzilla.redhat.com/show_bug.cgi?id=1464692
+
+Patches copied from ncurses patch release 20170701:
+
+ftp://invisible-island.net/ncurses/6.0/ncurses-6.0-20170701.patch.gz
+
+Excerpt from patch release announcement:
+
+ + add/improve checks in tic's parser to address invalid input
+   (Redhat #1464684, #1464685, #1464686, #1464691).
+   + alloc_entry.c, add a check for a null-pointer.
+   + parse_entry.c, add several checks for valid pointers as well as
+     one check to ensure that a single character on a line is not
+     treated as the 2-character termcap short-name.
+ + the fixes for Redhat #1464685 obscured a problem subsequently
+   reported in Redhat #1464687; the given test-case was no longer
+   reproducible.  Testing without the fixes for the earlier reports
+   showed a problem with buffer overflow in dump_entry.c, which is
+   addressed by reducing the use of a fixed-size buffer.
+
+https://lists.gnu.org/archive/html/bug-ncurses/2017-07/msg00001.html
+
+--- ncurses-6.0-20170624+/ncurses/tinfo/alloc_entry.c	2017-04-09 23:33:51.000000000 +0000
++++ ncurses-6.0-20170701/ncurses/tinfo/alloc_entry.c	2017-06-27 23:48:55.000000000 +0000
+@@ -96,7 +96,11 @@
+ {
+     char *result = 0;
+     size_t old_next_free = next_free;
+-    size_t len = strlen(string) + 1;
++    size_t len;
++
++    if (string == 0)
++	return _nc_save_str("");
++    len = strlen(string) + 1;
+ 
+     if (len == 1 && next_free != 0) {
+ 	/*
+--- ncurses-6.0-20170624+/ncurses/tinfo/parse_entry.c	2017-06-24 22:59:46.000000000 +0000
++++ ncurses-6.0-20170701/ncurses/tinfo/parse_entry.c	2017-06-28 00:53:12.000000000 +0000
+@@ -236,13 +236,14 @@
+      * implemented it.  Note that the resulting terminal type was never the
+      * 2-character name, but was instead the first alias after that.
+      */
++#define ok_TC2(s) (isgraph(UChar(s)) && (s) != '|')
+     ptr = _nc_curr_token.tk_name;
+     if (_nc_syntax == SYN_TERMCAP
+ #if NCURSES_XNAMES
+ 	&& !_nc_user_definable
+ #endif
+ 	) {
+-	if (ptr[2] == '|') {
++	if (ok_TC2(ptr[0]) && ok_TC2(ptr[1]) && (ptr[2] == '|')) {
+ 	    ptr += 3;
+ 	    _nc_curr_token.tk_name[2] = '\0';
+ 	}
+@@ -284,9 +285,11 @@
+ 	if (is_use || is_tc) {
+ 	    entryp->uses[entryp->nuses].name = _nc_save_str(_nc_curr_token.tk_valstring);
+ 	    entryp->uses[entryp->nuses].line = _nc_curr_line;
+-	    entryp->nuses++;
+-	    if (entryp->nuses > 1 && is_tc) {
+-		BAD_TC_USAGE
++	    if (VALID_STRING(entryp->uses[entryp->nuses].name)) {
++		entryp->nuses++;
++		if (entryp->nuses > 1 && is_tc) {
++		    BAD_TC_USAGE
++		}
+ 	    }
+ 	} else {
+ 	    /* normal token lookup */
+@@ -588,7 +591,7 @@
+ static void
+ append_acs(string_desc * dst, int code, char *src)
+ {
+-    if (src != 0 && strlen(src) == 1) {
++    if (VALID_STRING(src) && strlen(src) == 1) {
+ 	append_acs0(dst, code, *src);
+     }
+ }
+@@ -849,15 +852,14 @@
+ 	    }
+ 
+ 	    if (tp->Strings[to_ptr->nte_index]) {
++		const char *s = tp->Strings[from_ptr->nte_index];
++		const char *t = tp->Strings[to_ptr->nte_index];
+ 		/* There's no point in warning about it if it's the same
+ 		 * string; that's just an inefficiency.
+ 		 */
+-		if (strcmp(
+-			      tp->Strings[from_ptr->nte_index],
+-			      tp->Strings[to_ptr->nte_index]) != 0)
++		if (VALID_STRING(s) && VALID_STRING(t) && strcmp(s, t) != 0)
+ 		    _nc_warning("%s (%s) already has an explicit value %s, ignoring ko",
+-				ap->to, ap->from,
+-				_nc_visbuf(tp->Strings[to_ptr->nte_index]));
++				ap->to, ap->from, t);
+ 		continue;
+ 	    }
+ 
+--- ncurses-6.0-20170624+/progs/dump_entry.c	2017-06-23 22:47:43.000000000 +0000
++++ ncurses-6.0-20170701/progs/dump_entry.c	2017-07-01 11:27:29.000000000 +0000
+@@ -841,9 +841,10 @@
+     PredIdx num_strings = 0;
+     bool outcount = 0;
+ 
+-#define WRAP_CONCAT	\
+-	wrap_concat(buffer); \
+-	outcount = TRUE
++#define WRAP_CONCAT1(s)		wrap_concat(s); outcount = TRUE
++#define WRAP_CONCAT2(a,b)	wrap_concat(a); WRAP_CONCAT1(b)
++#define WRAP_CONCAT3(a,b,c)	wrap_concat(a); WRAP_CONCAT2(b,c)
++#define WRAP_CONCAT		WRAP_CONCAT1(buffer)
+ 
+     len = 12;			/* terminfo file-header */
+ 
+@@ -1007,9 +1008,9 @@
+ 		    set_attributes = save_sgr;
+ 
+ 		    trimmed_sgr0 = _nc_trim_sgr0(tterm);
+-		    if (strcmp(capability, trimmed_sgr0))
++		    if (strcmp(capability, trimmed_sgr0)) {
+ 			capability = trimmed_sgr0;
+-		    else {
++		    } else {
+ 			if (trimmed_sgr0 != exit_attribute_mode)
+ 			    free(trimmed_sgr0);
+ 		    }
+@@ -1046,13 +1047,21 @@
+ 			_nc_SPRINTF(buffer, _nc_SLIMIT(sizeof(buffer))
+ 				    "%s=!!! %s WILL NOT CONVERT !!!",
+ 				    name, srccap);
++			WRAP_CONCAT;
+ 		    } else if (suppress_untranslatable) {
+ 			continue;
+ 		    } else {
+ 			char *s = srccap, *d = buffer;
+-			_nc_SPRINTF(d, _nc_SLIMIT(sizeof(buffer)) "..%s=", name);
+-			d += strlen(d);
++			WRAP_CONCAT3("..", name, "=");
+ 			while ((*d = *s++) != 0) {
++			    if ((d - buffer - 1) >= (int) sizeof(buffer)) {
++				fprintf(stderr,
++					"%s: value for %s is too long\n",
++					_nc_progname,
++					name);
++				*d = '\0';
++				break;
++			    }
+ 			    if (*d == ':') {
+ 				*d++ = '\\';
+ 				*d = ':';
+@@ -1061,13 +1070,12 @@
+ 			    }
+ 			    d++;
+ 			}
++			WRAP_CONCAT;
+ 		    }
+ 		} else {
+-		    _nc_SPRINTF(buffer, _nc_SLIMIT(sizeof(buffer))
+-				"%s=%s", name, cv);
++		    WRAP_CONCAT3(name, "=", cv);
+ 		}
+ 		len += (int) strlen(capability) + 1;
+-		WRAP_CONCAT;
+ 	    } else {
+ 		char *src = _nc_tic_expand(capability,
+ 					   outform == F_TERMINFO, numbers);
+@@ -1083,8 +1091,7 @@
+ 		    strcpy_DYN(&tmpbuf, src);
+ 		}
+ 		len += (int) strlen(capability) + 1;
+-		wrap_concat(tmpbuf.text);
+-		outcount = TRUE;
++		WRAP_CONCAT1(tmpbuf.text);
+ 	    }
+ 	}
+ 	/* e.g., trimmed_sgr0 */
+@@ -1526,7 +1533,8 @@
+ 		}
+ 		if (len > critlen) {
+ 		    (void) fprintf(stderr,
+-				   "warning: %s entry is %d bytes long\n",
++				   "%s: %s entry is %d bytes long\n",
++				   _nc_progname,
+ 				   _nc_first_name(tterm->term_names),
+ 				   len);
+ 		    SHOW_WHY("# WARNING: this entry, %d bytes long, may core-dump %s libraries!\n",
-- 
2.13.2