shells: do not allow bare "read" in non-bash compat configs

    On Sat, Feb 9, 2019 Cristian Ionescu-Idbohrn wrote:
    > In my case (at work), I have to watch and prevent people from doing
    > unportable things.  For me, that's a burden.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 05c47950f..bcf7a3470 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -14161,6 +14161,10 @@ readcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                 }
         }
 
+        if (!ENABLE_ASH_BASH_COMPAT && !argptr) {
+                bb_simple_error_msg("read: need variable name");
+                return 1;
+        }
         params.argv = argptr;
         params.setvar = setvar0;
         params.ifs = bltinlookup("IFS"); /* can be NULL */