From 86ff1772f25dff819c1983418ac36822745a6d19 Mon Sep 17 00:00:00 2001
From: Ron Yorston <rmy@pobox.com>
Date: Sun, 16 Apr 2023 10:03:09 +0100
Subject: ash: more Unix-style path fixes

Commit 950b318a2 (ash: Unix-style paths, shell builtins and applets)
broke running of Unix-style absolute paths from the shell by PATH
search.  The copy of the program name on the stack should only be
used in the first call to tryexec() otherwise it interferes with the
use of the stack by padvance().

Also, bring the code to handle Unix-style paths in find_command()
into line with the revised code in shellexec().
---
 shell/ash.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/shell/ash.c b/shell/ash.c
index 0443f1a02..3eb9d5852 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -9081,9 +9081,11 @@ static void shellexec(char *prog, char **argv, const char *path, int idx)
 #endif
 	) {
 #if ENABLE_PLATFORM_MINGW32
-		prog = stack_add_ext_space(prog);
-#endif
+		char *progext = stack_add_ext_space(prog);
+		tryexec(IF_FEATURE_SH_STANDALONE(applet_no,) progext, argv, envp);
+#else
 		tryexec(IF_FEATURE_SH_STANDALONE(applet_no,) prog, argv, envp);
+#endif
 		if (applet_no >= 0) {
 			/* We tried execing ourself, but it didn't work.
 			 * Maybe /proc/self/exe doesn't exist?
@@ -9094,15 +9096,15 @@ static void shellexec(char *prog, char **argv, const char *path, int idx)
 		e = errno;
 #if ENABLE_PLATFORM_MINGW32
 		if (unix_path(prog)) {
-# if ENABLE_FEATURE_SH_STANDALONE
 			const char *name = bb_basename(prog);
+# if ENABLE_FEATURE_SH_STANDALONE
 			if ((applet_no = find_applet_by_name(name)) >= 0) {
 				tryexec(applet_no, name, argv, envp);
 				e = errno;
 			}
 # endif
-			if (!find_builtin(bb_basename(prog))) {
-				argv[0] = (char *)bb_basename(prog);
+			if (!find_builtin(name)) {
+				argv[0] = (char *)name;
 				goto try_PATH;
 			}
 		}
@@ -14860,9 +14862,19 @@ find_command(char *name, struct cmdentry *entry, int act, const char *path)
 		fullname = stack_add_ext_space(name);
 		if (add_win32_extension(fullname) || file_is_executable(fullname)) {
 			return;
-		} else if (unix_path(name) && !find_builtin(bb_basename(name))) {
+		} else if (unix_path(name)) {
 			name = (char *)bb_basename(name);
-			act |= DO_NOFUNC;
+			if (
+# if ENABLE_FEATURE_SH_STANDALONE
+					find_applet_by_name(name) >= 0 ||
+# endif
+					!find_builtin(bb_basename(name))
+			) {
+				act |= DO_NOFUNC;
+			} else if (act & DO_ABS) {
+				entry->cmdtype = CMDUNKNOWN;
+				return;
+			}
 		} else if (act & DO_ABS) {
 			entry->cmdtype = CMDUNKNOWN;
 			return;
-- 
cgit v1.2.3-55-g6feb