Resolves: #1558532 - fix crash of 'nano --restrict when <Insert> is pressed

0001-nano-2.9.4-restrict-crash.patch

@@ -0,0 +1,147 @@
+From 4cdad8299f605e8b0527391a49311786e0bca35c Mon Sep 17 00:00:00 2001
+From: Kamil Dudka <kdudka@redhat.com>
+Date: Tue, 20 Mar 2018 16:49:34 +0100
+Subject: [PATCH 1/2] input: do not crash if sctofunc() returns NULL
+
+This fixes a regression introduced by commit 54103d8e: a crash that
+can be triggered by running 'nano --restrict' and pressing <Insert>.
+
+This addresses https://bugzilla.redhat.com/1558532.
+
+Upstream-commit: b830a7dd384495fb9b882f866b26948025abe136
+Signed-off-by: Kamil Dudka <kdudka@redhat.com>
+---
+ src/nano.c | 16 +++++++++++-----
+ 1 file changed, 11 insertions(+), 5 deletions(-)
+
+diff --git a/src/nano.c b/src/nano.c
+index ad95925..e7b6d62 100644
+--- a/src/nano.c
++++ b/src/nano.c
+@@ -1712,9 +1712,12 @@ int do_input(bool allow_funcs)
+ 	if (shortcut == NULL)
+ 		pletion_line = NULL;
+ 	else {
+-		if (ISSET(VIEW_MODE) && !sctofunc(shortcut)->viewok) {
+-			print_view_warning();
+-			return ERR;
++		if (ISSET(VIEW_MODE)) {
++			const subnfunc *f = sctofunc(shortcut);
++			if (f && !f->viewok) {
++				print_view_warning();
++				return ERR;
++			}
+ 		}
+ 
+ 		/* If the function associated with this shortcut is
+@@ -1787,8 +1790,11 @@ int do_input(bool allow_funcs)
+ 				wrap_reset();
+ #endif
+ #ifdef ENABLE_COLOR
+-			if (!refresh_needed && !sctofunc(shortcut)->viewok)
+-				check_the_multis(openfile->current);
++			if (!refresh_needed) {
++				const subnfunc *f = sctofunc(shortcut);
++				if (f && !f->viewok)
++					check_the_multis(openfile->current);
++			}
+ #endif
+ 			if (!refresh_needed && (shortcut->func == do_delete ||
+ 									shortcut->func == do_backspace))
+-- 
+2.14.3
+
+
+From 25a02d16fc59bbe88cdc51922534436b20187a3d Mon Sep 17 00:00:00 2001
+From: Benno Schulenberg <bensberg@telfort.nl>
+Date: Tue, 20 Mar 2018 19:56:03 +0100
+Subject: [PATCH 2/2] tweaks: factor out the check for 'viewok' into its own
+ function
+
+And also prevent a theoretical crash for restricted prompt functions.
+
+Upstream-commit: 8b8c6bb818b21b9c7fcf7481df7154745b4aad41
+Signed-off-by: Kamil Dudka <kdudka@redhat.com>
+---
+ src/nano.c   | 24 +++++++++++++-----------
+ src/prompt.c |  2 +-
+ src/proto.h  |  1 +
+ 3 files changed, 15 insertions(+), 12 deletions(-)
+
+diff --git a/src/nano.c b/src/nano.c
+index e7b6d62..c39622b 100644
+--- a/src/nano.c
++++ b/src/nano.c
+@@ -1621,6 +1621,14 @@ int do_mouse(void)
+ }
+ #endif /* ENABLE_MOUSE */
+ 
++/* Return TRUE when the given shortcut is valid in view mode. */
++bool okay_for_view(const sc *shortcut)
++{
++	const subnfunc *func = sctofunc(shortcut);
++
++	return (func && func->viewok);
++}
++
+ /* Read in a keystroke.  Act on the keystroke if it is a shortcut or a toggle;
+  * otherwise, insert it into the edit buffer.  If allow_funcs is FALSE, don't
+  * do anything with the keystroke -- just return it. */
+@@ -1712,12 +1720,9 @@ int do_input(bool allow_funcs)
+ 	if (shortcut == NULL)
+ 		pletion_line = NULL;
+ 	else {
+-		if (ISSET(VIEW_MODE)) {
+-			const subnfunc *f = sctofunc(shortcut);
+-			if (f && !f->viewok) {
+-				print_view_warning();
+-				return ERR;
+-			}
++		if (ISSET(VIEW_MODE) && !okay_for_view(shortcut)) {
++			print_view_warning();
++			return ERR;
+ 		}
+ 
+ 		/* If the function associated with this shortcut is
+@@ -1790,11 +1795,8 @@ int do_input(bool allow_funcs)
+ 				wrap_reset();
+ #endif
+ #ifdef ENABLE_COLOR
+-			if (!refresh_needed) {
+-				const subnfunc *f = sctofunc(shortcut);
+-				if (f && !f->viewok)
+-					check_the_multis(openfile->current);
+-			}
++			if (!refresh_needed && !okay_for_view(shortcut))
++				check_the_multis(openfile->current);
+ #endif
+ 			if (!refresh_needed && (shortcut->func == do_delete ||
+ 									shortcut->func == do_backspace))
+diff --git a/src/prompt.c b/src/prompt.c
+index e8fbbc0..8ec74fd 100644
+--- a/src/prompt.c
++++ b/src/prompt.c
+@@ -171,7 +171,7 @@ int do_statusbar_input(bool *finished)
+ 			/* Handle any other shortcut in the current menu, setting finished
+ 			 * to TRUE to indicate that we're done after running or trying to
+ 			 * run its associated function. */
+-			if (!ISSET(VIEW_MODE) || sctofunc(shortcut)->viewok)
++			if (!ISSET(VIEW_MODE) || okay_for_view(shortcut))
+ 				shortcut->func();
+ 			*finished = TRUE;
+ 		}
+diff --git a/src/proto.h b/src/proto.h
+index 86f53d7..5530a90 100644
+--- a/src/proto.h
++++ b/src/proto.h
+@@ -441,6 +441,7 @@ void disable_flow_control(void);
+ void enable_flow_control(void);
+ void terminal_init(void);
+ void unbound_key(int code);
++bool okay_for_view(const sc *shortcut);
+ int do_input(bool allow_funcs);
+ void do_output(char *output, size_t output_len, bool allow_cntrls);
+ 
+-- 
+2.14.3
+

nano.spec

@@ -1,7 +1,7 @@
 Summary:         A small text editor
 Name:            nano
 Version:         2.9.4
-Release:         1%{?dist}
+Release:         2%{?dist}
 License:         GPLv3+
 URL:             https://www.nano-editor.org
 Source:          https://www.nano-editor.org/dist/v2.9/%{name}-%{version}.tar.gz
@@ -19,6 +19,9 @@ Conflicts:       filesystem < 3
 Requires(post):  /sbin/install-info
 Requires(preun): /sbin/install-info
 
+# fix crash of 'nano --restrict when <Insert> is pressed (#1558532)
+Patch1:    0001-nano-2.9.4-restrict-crash.patch
+
 %description
 GNU nano is a small and friendly text editor.
 
@@ -80,6 +83,9 @@ exit 0
 %{_datadir}/nano
 
 %changelog
+* Wed Mar 21 2018 Kamil Dudka <kdudka@redhat.com> - 2.9.4-2
+- fix crash of 'nano --restrict when <Insert> is pressed (#1558532)
+
 * Thu Mar 08 2018 Kamil Dudka <kdudka@redhat.com> - 2.9.4-1
 - new upstream release