From e705b19d489f769228902e100b4f375c03becfbb Mon Sep 17 00:00:00 2001 From: Tony Ambardar Date: Tue, 20 Apr 2021 01:26:36 -0700 Subject: [PATCH] ip: drop 2-char command assumption The 'ip' utility hardcodes the assumption of being a 2-char command, where any follow-on characters are passed as an argument: $ ./ip-full help Object "-full" is unknown, try "ip help". This confusing behaviour isn't seen with 'tc' for example, and was added in a 2005 commit without documentation. It was noticed during testing of 'ip' variants built/packaged with different feature sets (e.g. w/o BPF support). Mitigate the problem by redoing the command without the 2-char assumption if the follow-on characters fail to parse as a valid command. Fixes: 351efcde4e62 ("Update header files to 2.6.14") Signed-off-by: Tony Ambardar Signed-off-by: David Ahern Conflict: batch function has refactor Reference: https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/commit?id=e705b19d489f769228902e100b4f375c03becfbb --- ip/ip.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/ip/ip.c b/ip/ip.c index 90392c2..90c04dc 100644 --- a/ip/ip.c +++ b/ip/ip.c @@ -107,7 +107,7 @@ static const struct cmd { { 0 } }; -static int do_cmd(const char *argv0, int argc, char **argv) +static int do_cmd(const char *argv0, int argc, char **argv, bool final) { const struct cmd *c; @@ -116,7 +116,8 @@ static int do_cmd(const char *argv0, int argc, char **argv) return -(c->func(argc-1, argv+1)); } - fprintf(stderr, "Object \"%s\" is unknown, try \"ip help\".\n", argv0); + if (final) + fprintf(stderr, "Object \"%s\" is unknown, try \"ip help\".\n", argv0); return EXIT_FAILURE; } @@ -154,7 +155,7 @@ static int batch(const char *name) if (largc == 0) continue; /* blank line */ - if (do_cmd(largv[0], largc, largv)) { + if (do_cmd(largv[0], largc, largv, true)) { fprintf(stderr, "Command failed %s:%d\n", name, cmdlineno); ret = EXIT_FAILURE; @@ -315,11 +316,15 @@ int main(int argc, char **argv) rtnl_set_strict_dump(&rth); - if (strlen(basename) > 2) - return do_cmd(basename+2, argc, argv); + if (strlen(basename) > 2) { + int ret = do_cmd(basename+2, argc, argv, false); + if (ret != EXIT_FAILURE) + return ret; + } + if (argc > 1) - return do_cmd(argv[1], argc-1, argv+1); + return do_cmd(argv[1], argc-1, argv+1, true); rtnl_close(&rth); usage(); -- 2.23.0