From 21da9912d453a8a3b9c05309b2c7c24774d233d3 Mon Sep 17 00:00:00 2001 From: Christian Seiler Date: Wed, 6 Mar 2013 20:41:54 +0100 Subject: [PATCH] lxc-attach: Default to /bin/sh if shell cannot be determined or exec'd If getpwuid() fails and also the fallback of spawning of a 'getent' process, and the user specified no command to execute, default to /bin/sh and only fail if even that is not available. This should ensure that unless the container is *really* weird, no matter what, the user should always end up with a shell when calling lxc-attach with no further arguments. Signed-off-by: Christian Seiler --- src/lxc/lxc_attach.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/src/lxc/lxc_attach.c b/src/lxc/lxc_attach.c index fdf8a0664..69ebfacca 100644 --- a/src/lxc/lxc_attach.c +++ b/src/lxc/lxc_attach.c @@ -452,18 +452,24 @@ int main(int argc, char *argv[]) else user_shell = passwd->pw_shell; - if (!user_shell) { - SYSERROR("failed to get passwd " \ - "entry for uid '%d'", uid); - return -1; - } - - { + if (user_shell) { char *const args[] = { user_shell, NULL, }; + (void) execvp(args[0], args); + } + + /* executed if either no passwd entry or execvp fails, + * we will fall back on /bin/sh as a default shell + */ + { + char *const args[] = { + "/bin/sh", + NULL, + }; + execvp(args[0], args); SYSERROR("failed to exec '%s'", args[0]); return -1;