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().

1 files 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;