| Message ID | 20210420082636.1210305-1-Tony.Ambardar@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [iproute2,v2] ip: drop 2-char command assumption | expand |
On 4/20/21 1:26 AM, Tony Ambardar wrote: > 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 <Tony.Ambardar@gmail.com> > --- > v2: (feedback from David Ahern) > * work around problem but remain compatible with 2-char assumption > > --- > ip/ip.c | 16 ++++++++++------ > 1 file changed, 10 insertions(+), 6 deletions(-) > Applied. Thanks,
diff --git a/ip/ip.c b/ip/ip.c index 4cf09fc3..8e4c6eb5 100644 --- a/ip/ip.c +++ b/ip/ip.c @@ -125,7 +125,7 @@ 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; @@ -134,7 +134,8 @@ 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; } @@ -143,7 +144,7 @@ static int ip_batch_cmd(int argc, char *argv[], void *data) const int *orig_family = data; preferred_family = *orig_family; - return do_cmd(argv[0], argc, argv); + return do_cmd(argv[0], argc, argv, true); } static int batch(const char *name) @@ -313,11 +314,14 @@ 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();
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 <Tony.Ambardar@gmail.com> --- v2: (feedback from David Ahern) * work around problem but remain compatible with 2-char assumption --- ip/ip.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)