From 6e7739fc938c1ec58d321f70ea41d9548a4cca0f Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Fri, 31 May 2019 11:53:33 +0100 Subject: [PATCH] Smack: Restore the smackfsdef mount option and add missing prefixes The 5.1 mount system rework changed the smackfsdef mount option to smackfsdefault. This fixes the regression by making smackfsdef treated the same way as smackfsdefault. Also fix the smack_param_specs[] to have "smack" prefixes on all the names. This isn't visible to a user unless they either: (a) Try to mount a filesystem that's converted to the internal mount API and that implements the ->parse_monolithic() context operation - and only then if they call security_fs_context_parse_param() rather than security_sb_eat_lsm_opts(). There are no examples of this upstream yet, but nfs will probably want to do this for nfs2 or nfs3. (b) Use fsconfig() to configure the filesystem - in which case security_fs_context_parse_param() will be called. This issue is that smack_sb_eat_lsm_opts() checks for the "smack" prefix on the options, but smack_fs_context_parse_param() does not. Fixes: c3300aaf95fb ("smack: get rid of match_token()") Fixes: 2febd254adc4 ("smack: Implement filesystem context security hooks") Cc: stable@vger.kernel.org Reported-by: Jose Bollo Signed-off-by: Casey Schaufler Signed-off-by: David Howells Tested-by: Casey Schaufler Signed-off-by: Linus Torvalds --- security/smack/smack_lsm.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 0de725f88bed..d99450b4f511 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -68,6 +68,7 @@ static struct { int len; int opt; } smk_mount_opts[] = { + {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault}, A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute) }; #undef A @@ -682,11 +683,12 @@ static int smack_fs_context_dup(struct fs_context *fc, } static const struct fs_parameter_spec smack_param_specs[] = { - fsparam_string("fsdefault", Opt_fsdefault), - fsparam_string("fsfloor", Opt_fsfloor), - fsparam_string("fshat", Opt_fshat), - fsparam_string("fsroot", Opt_fsroot), - fsparam_string("fstransmute", Opt_fstransmute), + fsparam_string("smackfsdef", Opt_fsdefault), + fsparam_string("smackfsdefault", Opt_fsdefault), + fsparam_string("smackfsfloor", Opt_fsfloor), + fsparam_string("smackfshat", Opt_fshat), + fsparam_string("smackfsroot", Opt_fsroot), + fsparam_string("smackfstransmute", Opt_fstransmute), {} };