[git commit] hush: fix SEGV on "echo << >" and such

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=e9c21c5c3a698468be1daceaad931901e1d63aed
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master

function                                             old     new   delta
.rodata                                           105787  105823     +36
fetch_heredocs                                       461     477     +16
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 52/0)               Total: 52 bytes

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 shell/hush.c                                                  | 5 +++++
 shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.right | 1 +
 shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.tests | 2 ++
 shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.right | 1 +
 shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.tests | 2 ++
 5 files changed, 11 insertions(+)

diff --git a/shell/hush.c b/shell/hush.c
index 0b2bc01f5..d1f687f9d 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -4625,6 +4625,11 @@ static int fetch_heredocs(o_string *as_string, struct pipe *pi, int heredoc_cnt,
 
 					redir->rd_type = REDIRECT_HEREDOC2;
 					/* redir->rd_dup is (ab)used to indicate <<- */
+					if (!redir->rd_filename) {
+						/* examples: "echo <<", "echo <<<", "echo <<>" */
+						syntax_error("missing here document terminator");
+						return -1;
+					}
 					p = fetch_till_str(as_string, input,
 							redir->rd_filename, redir->rd_dup);
 					if (!p) {
diff --git a/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.right b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.right
new file mode 100644
index 000000000..7af73557a
--- /dev/null
+++ b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.right
@@ -0,0 +1 @@
+hush: syntax error: missing here document terminator
diff --git a/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.tests b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.tests
new file mode 100755
index 000000000..33ccde26b
--- /dev/null
+++ b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF1.tests
@@ -0,0 +1,2 @@
+echo <<
+echo Done:
diff --git a/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.right b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.right
new file mode 100644
index 000000000..7af73557a
--- /dev/null
+++ b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.right
@@ -0,0 +1 @@
+hush: syntax error: missing here document terminator
diff --git a/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.tests b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.tests
new file mode 100755
index 000000000..fcda11045
--- /dev/null
+++ b/shell/hush_test/hush-heredoc/heredoc_syntax_err_no_EOF2.tests
@@ -0,0 +1,2 @@
+echo << >
+echo Done: