Commit f876df9f authored Aug 09, 2022 by Mike Snitzer

dm verity: fix verity_parse_opt_args parsing



Commit df326e7a ("dm verity: allow optional args to alter primary
args handling") introduced a bug where verity_parse_opt_args() wouldn't
properly shift past an optional argument's additional params (by
ignoring them).

Fix this by avoiding returning with error if an unknown argument is
encountered when @only_modifier_opts=true is passed to
verity_parse_opt_args().

In practice this regressed the cryptsetup testsuite's FEC testing
because unknown optional arguments were encountered, wherey
short-circuiting ever testing FEC mode. With this fix all of the
cryptsetup testsuite's verity FEC tests pass.

Fixes: df326e7a ("dm verity: allow optional args to alter primary args handling")
Reported-by: Milan Broz <gmazyland@gmail.com&gt;>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

parent 8c22816d

drivers/md/dm-verity-target.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -1052,7 +1052,7 @@ static int verity_parse_opt_args(struct dm_arg_set as, struct dm_verity v,
		struct dm_verity_sig_opts *verify_args,
		bool only_modifier_opts)
		{
		int r;
		int r = 0;
		unsigned argc;
		struct dm_target *ti = v->ti;
		const char *arg_name;
		@@ -1122,8 +1122,18 @@ static int verity_parse_opt_args(struct dm_arg_set as, struct dm_verity v,
		if (r)
		return r;
		continue;

		} else if (only_modifier_opts) {
		/*
		* Ignore unrecognized opt, could easily be an extra
		* argument to an option whose parsing was skipped.
		* Normal parsing (@only_modifier_opts=false) will
		* properly parse all options (and their extra args).
		*/
		continue;
		}

		DMERR("Unrecognized verity feature request: %s", arg_name);
		ti->error = "Unrecognized verity feature request";
		return -EINVAL;
		} while (argc && !r);