selinux: try to use preparsed sid before calling parse_sid()

Avoid unnecessary parsing of sids that have already been parsed via
selinux_sb_eat_lsm_opts().

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Scott Mayhew 2022-01-31 13:57:37 -05:00 committed by Paul Moore
parent b8b87fd954
commit 6bc1968c14
1 changed files with 59 additions and 29 deletions

View File

@ -675,36 +675,48 @@ static int selinux_set_mnt_opts(struct super_block *sb,
*/
if (opts) {
if (opts->fscontext) {
rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
if (rc)
goto out;
if (opts->fscontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
if (rc)
goto out;
} else
fscontext_sid = opts->fscontext_sid;
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
fscontext_sid))
goto out_double_mount;
sbsec->flags |= FSCONTEXT_MNT;
}
if (opts->context) {
rc = parse_sid(sb, opts->context, &context_sid);
if (rc)
goto out;
if (opts->context_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->context, &context_sid);
if (rc)
goto out;
} else
context_sid = opts->context_sid;
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
context_sid))
goto out_double_mount;
sbsec->flags |= CONTEXT_MNT;
}
if (opts->rootcontext) {
rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
if (rc)
goto out;
if (opts->rootcontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
if (rc)
goto out;
} else
rootcontext_sid = opts->rootcontext_sid;
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
rootcontext_sid))
goto out_double_mount;
sbsec->flags |= ROOTCONTEXT_MNT;
}
if (opts->defcontext) {
rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
if (rc)
goto out;
if (opts->defcontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
if (rc)
goto out;
} else
defcontext_sid = opts->defcontext_sid;
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
defcontext_sid))
goto out_double_mount;
@ -2709,7 +2721,6 @@ static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
{
struct selinux_mnt_opts *opts = mnt_opts;
struct superblock_security_struct *sbsec = selinux_superblock(sb);
u32 sid;
int rc;
if (!(sbsec->flags & SE_SBINITIALIZED))
@ -2719,33 +2730,48 @@ static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
return 0;
if (opts->fscontext) {
rc = parse_sid(sb, opts->fscontext, &sid);
if (rc)
return rc;
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
if (opts->fscontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->fscontext,
&opts->fscontext_sid);
if (rc)
return rc;
}
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
opts->fscontext_sid))
goto out_bad_option;
}
if (opts->context) {
rc = parse_sid(sb, opts->context, &sid);
if (rc)
return rc;
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
if (opts->context_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->context, &opts->context_sid);
if (rc)
return rc;
}
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
opts->context_sid))
goto out_bad_option;
}
if (opts->rootcontext) {
struct inode_security_struct *root_isec;
root_isec = backing_inode_security(sb->s_root);
rc = parse_sid(sb, opts->rootcontext, &sid);
if (rc)
return rc;
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
if (opts->rootcontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->rootcontext,
&opts->rootcontext_sid);
if (rc)
return rc;
}
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
opts->rootcontext_sid))
goto out_bad_option;
}
if (opts->defcontext) {
rc = parse_sid(sb, opts->defcontext, &sid);
if (rc)
return rc;
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
if (opts->defcontext_sid == SECSID_NULL) {
rc = parse_sid(sb, opts->defcontext,
&opts->defcontext_sid);
if (rc)
return rc;
}
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
opts->defcontext_sid))
goto out_bad_option;
}
return 0;
@ -2843,6 +2869,10 @@ static int selinux_fs_context_dup(struct fs_context *fc,
if (!opts->defcontext)
return -ENOMEM;
}
opts->fscontext_sid = src->fscontext_sid;
opts->context_sid = src->context_sid;
opts->rootcontext_sid = src->rootcontext_sid;
opts->defcontext_sid = src->defcontext_sid;
return 0;
}