From: Ondrej Mosnacek omosnace@redhat.com
commit aff7ed4851680d0d28ad9f52cd2f99213e1371b2 upstream.
These strings may come from untrusted sources (e.g. file xattrs) so they need to be properly escaped.
Reproducer: # setenforce 0 # touch /tmp/test # setfattr -n security.selinux -v 'kuřecí řízek' /tmp/test # runcon system_u:system_r:sshd_t:s0 cat /tmp/test (look at the generated AVCs)
Actual result: type=AVC [...] trawcon=kuřecí řízek
Expected result: type=AVC [...] trawcon=6B75C5996563C3AD20C599C3AD7A656B
Fixes: fede148324c3 ("selinux: log invalid contexts in AVCs") Cc: stable@vger.kernel.org # v5.1+ Signed-off-by: Ondrej Mosnacek omosnace@redhat.com Acked-by: Richard Guy Briggs rgb@redhat.com Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- security/selinux/avc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
--- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -739,14 +739,20 @@ static void avc_audit_post_callback(stru rc = security_sid_to_context_inval(sad->state, sad->ssid, &scontext, &scontext_len); if (!rc && scontext) { - audit_log_format(ab, " srawcon=%s", scontext); + if (scontext_len && scontext[scontext_len - 1] == '\0') + scontext_len--; + audit_log_format(ab, " srawcon="); + audit_log_n_untrustedstring(ab, scontext, scontext_len); kfree(scontext); }
rc = security_sid_to_context_inval(sad->state, sad->tsid, &scontext, &scontext_len); if (!rc && scontext) { - audit_log_format(ab, " trawcon=%s", scontext); + if (scontext_len && scontext[scontext_len - 1] == '\0') + scontext_len--; + audit_log_format(ab, " trawcon="); + audit_log_n_untrustedstring(ab, scontext, scontext_len); kfree(scontext); } }