From aefe1c260ec5aa691e8b6f773c7fa393bfad0f7b Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Mon, 7 Mar 2011 12:02:40 +0100 Subject: ash: fix execution of shell scripts without shebang We were assuming #!/bin/sh, whereas we had to simply re-enter ash. Signed-off-by: Denys Vlasenko --- shell/ash.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/shell/ash.c b/shell/ash.c index c3c953656..09db046fe 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -7396,8 +7396,6 @@ static int builtinloc = -1; /* index in path of %builtin, or -1 */ static void tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) char *cmd, char **argv, char **envp) { - int repeated = 0; - #if ENABLE_FEATURE_SH_STANDALONE if (applet_no >= 0) { if (APPLET_IS_NOEXEC(applet_no)) { @@ -7421,25 +7419,36 @@ tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) char *cmd, char **argv, char ** #else execve(cmd, argv, envp); #endif - if (repeated) { + if (cmd == (char*) bb_busybox_exec_path) { + /* We already visited ENOEXEC branch below, don't do it again */ +//TODO: try execve(initial_argv0_of_shell, argv, envp) before giving up? free(argv); return; } if (errno == ENOEXEC) { + /* Run "cmd" as a shell script: + * http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html + * "If the execve() function fails with ENOEXEC, the shell + * shall execute a command equivalent to having a shell invoked + * with the command name as its first operand, + * with any remaining arguments passed to the new shell" + * + * That is, do not use $SHELL, user's shell, or /bin/sh; + * just call ourselves. + */ char **ap; char **new; for (ap = argv; *ap; ap++) continue; - ap = new = ckmalloc((ap - argv + 2) * sizeof(ap[0])); - ap[1] = cmd; - ap[0] = cmd = (char *)DEFAULT_SHELL; - ap += 2; - argv++; - while ((*ap++ = *argv++) != NULL) + new = ckmalloc((ap - argv + 2) * sizeof(new[0])); + new[0] = (char*) "ash"; + new[1] = cmd; + ap = new + 2; + while ((*ap++ = *++argv) != NULL) continue; + cmd = (char*) bb_busybox_exec_path; argv = new; - repeated++; goto repeat; } } -- cgit v1.2.3