klibc - Mar 2020 - [klibc:update-dash] dash: eval: Only restore exit status on exit/return

Commit-ID:  0d63aab8d433cd244e221aee978d2bcd4153cd1a
Gitweb:    
http://git.kernel.org/?p=libs/klibc/klibc.git;a=commit;h=0d63aab8d433cd244e221aee978d2bcd4153cd1a
Author:     Herbert Xu <herbert at gondor.apana.org.au>
AuthorDate: Fri, 14 Dec 2018 13:52:02 +0800
Committer:  Ben Hutchings <ben at decadent.org.uk>
CommitDate: Sat, 28 Mar 2020 21:42:55 +0000

[klibc] dash: eval: Only restore exit status on exit/return

[ dash commit 62cf6955f8abe875752d7163f6f3adbc7e49ebae ]

We unconditionally restore the saved status in exitreset, which
is incorrect as we only want to do it for exitcmd and returncmd.
This patch fixes the problem by introducing EXEND.

Reported-by: Martijn Dekker <martijn at inlv.org>
Fixes: da30b4b78769 ("[BUILTIN] Exit without arguments in a trap...")
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben at decadent.org.uk>

---
 usr/dash/error.h | 3 ++-
 usr/dash/eval.c  | 9 +++++----
 usr/dash/exec.c  | 2 +-
 usr/dash/main.c  | 2 +-
 usr/dash/trap.c  | 5 ++++-
 5 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/usr/dash/error.h b/usr/dash/error.h
index f91d11d1..8df0134f 100644
--- a/usr/dash/error.h
+++ b/usr/dash/error.h
@@ -69,7 +69,8 @@ extern int exception;
 /* exceptions */
 #define EXINT 0		/* SIGINT received */
 #define EXERROR 1	/* a generic error */
-#define EXEXIT 4	/* exit the shell */
+#define EXEND 3		/* exit the shell */
+#define EXEXIT 4	/* exit the shell via exitcmd */
 
 
 /*
diff --git a/usr/dash/eval.c b/usr/dash/eval.c
index bba0e7f8..1aad31a0 100644
--- a/usr/dash/eval.c
+++ b/usr/dash/eval.c
@@ -114,12 +114,13 @@ STATIC const struct builtincmd bltin = {
 INCLUDE "eval.h"
 
 EXITRESET {
-	evalskip = 0;
-	loopnest = 0;
 	if (savestatus >= 0) {
-		exitstatus = savestatus;
+		if (exception == EXEXIT || evalskip == SKIPFUNCDEF)
+			exitstatus = savestatus;
 		savestatus = -1;
 	}
+	evalskip = 0;
+	loopnest = 0;
 }
 #endif
 
@@ -318,7 +319,7 @@ out:
 
 	if (flags & EV_EXIT) {
 exexit:
-		exraise(EXEXIT);
+		exraise(EXEND);
 	}
 
 	popstackmark(&smark);
diff --git a/usr/dash/exec.c b/usr/dash/exec.c
index 9d0215a6..87354d49 100644
--- a/usr/dash/exec.c
+++ b/usr/dash/exec.c
@@ -143,7 +143,7 @@ shellexec(char **argv, const char *path, int idx)
 	exitstatus = exerrno;
 	TRACE(("shellexec failed for %s, errno %d, suppressint %d\n",
 		argv[0], e, suppressint ));
-	exerror(EXEXIT, "%s: %s", argv[0], errmsg(e, E_EXEC));
+	exerror(EXEND, "%s: %s", argv[0], errmsg(e, E_EXEC));
 	/* NOTREACHED */
 }
 
diff --git a/usr/dash/main.c b/usr/dash/main.c
index 6d53e009..6b3a0909 100644
--- a/usr/dash/main.c
+++ b/usr/dash/main.c
@@ -111,7 +111,7 @@ main(int argc, char **argv)
 		e = exception;
 
 		s = state;
-		if (e == EXEXIT || s == 0 || iflag == 0 || shlvl)
+		if (e == EXEND || e == EXEXIT || s == 0 || iflag == 0 || shlvl)
 			exitshell();
 
 		reset();
diff --git a/usr/dash/trap.c b/usr/dash/trap.c
index 1ad27e99..838008d2 100644
--- a/usr/dash/trap.c
+++ b/usr/dash/trap.c
@@ -42,6 +42,7 @@
 #include "main.h"
 #include "nodes.h"	/* for other headers */
 #include "eval.h"
+#include "init.h"
 #include "jobs.h"
 #include "show.h"
 #include "options.h"
@@ -396,8 +397,10 @@ exitshell(void)
 		trap[0] = NULL;
 		evalskip = 0;
 		evalstring(p, 0);
+		evalskip = SKIPFUNCDEF;
 	}
 out:
+	exitreset();
 	/*
 	 * Disable job control so that whoever had the foreground before we
 	 * started can get it back.
@@ -405,7 +408,7 @@ out:
 	if (likely(!setjmp(loc.loc)))
 		setjobctl(0);
 	flushall();
-	_exit(savestatus);
+	_exit(exitstatus);
 	/* NOTREACHED */
 }