aboutsummaryrefslogtreecommitdiff
path: root/security/apparmor/ipc.c
diff options
context:
space:
mode:
authorJohn Johansen <john.johansen@canonical.com>2017-12-08 17:43:18 -0800
committerJohn Johansen <john.johansen@canonical.com>2018-01-12 15:49:59 -0800
commit0dda0b3fb255048a221f736c8a2a24c674da8bf3 (patch)
tree2e608fa9c885466ab5d833bcbaff76620ada5db9 /security/apparmor/ipc.c
parentc92a9a461dff6140c539c61e457aa97df29517d6 (diff)
downloadlinux-stericsson-0dda0b3fb255048a221f736c8a2a24c674da8bf3.tar.gz
apparmor: fix ptrace label match when matching stacked labels
Given a label with a profile stack of A//&B or A//&C ... A ptrace rule should be able to specify a generic trace pattern with a rule like ptrace trace A//&**, however this is failing because while the correct label match routine is called, it is being done post label decomposition so it is always being done against a profile instead of the stacked label. To fix this refactor the cross check to pass the full peer label in to the label_match. Fixes: 290f458a4f16 ("apparmor: allow ptrace checks to be finer grained than just capability") Cc: Stable <stable@vger.kernel.org> Reported-by: Matthew Garrett <mjg59@google.com> Tested-by: Matthew Garrett <mjg59@google.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
Diffstat (limited to 'security/apparmor/ipc.c')
-rw-r--r--security/apparmor/ipc.c53
1 files changed, 32 insertions, 21 deletions
diff --git a/security/apparmor/ipc.c b/security/apparmor/ipc.c
index 7ca0032e7ba9..b40678f3c1d5 100644
--- a/security/apparmor/ipc.c
+++ b/security/apparmor/ipc.c
@@ -64,40 +64,48 @@ static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
FLAGS_NONE, GFP_ATOMIC);
}
+/* assumes check for PROFILE_MEDIATES is already done */
/* TODO: conditionals */
static int profile_ptrace_perm(struct aa_profile *profile,
- struct aa_profile *peer, u32 request,
- struct common_audit_data *sa)
+ struct aa_label *peer, u32 request,
+ struct common_audit_data *sa)
{
struct aa_perms perms = { };
- /* need because of peer in cross check */
- if (profile_unconfined(profile) ||
- !PROFILE_MEDIATES(profile, AA_CLASS_PTRACE))
- return 0;
-
- aad(sa)->peer = &peer->label;
- aa_profile_match_label(profile, &peer->label, AA_CLASS_PTRACE, request,
+ aad(sa)->peer = peer;
+ aa_profile_match_label(profile, peer, AA_CLASS_PTRACE, request,
&perms);
aa_apply_modes_to_perms(profile, &perms);
return aa_check_perms(profile, &perms, request, sa, audit_ptrace_cb);
}
-static int cross_ptrace_perm(struct aa_profile *tracer,
- struct aa_profile *tracee, u32 request,
- struct common_audit_data *sa)
+static int profile_tracee_perm(struct aa_profile *tracee,
+ struct aa_label *tracer, u32 request,
+ struct common_audit_data *sa)
{
+ if (profile_unconfined(tracee) || unconfined(tracer) ||
+ !PROFILE_MEDIATES(tracee, AA_CLASS_PTRACE))
+ return 0;
+
+ return profile_ptrace_perm(tracee, tracer, request, sa);
+}
+
+static int profile_tracer_perm(struct aa_profile *tracer,
+ struct aa_label *tracee, u32 request,
+ struct common_audit_data *sa)
+{
+ if (profile_unconfined(tracer))
+ return 0;
+
if (PROFILE_MEDIATES(tracer, AA_CLASS_PTRACE))
- return xcheck(profile_ptrace_perm(tracer, tracee, request, sa),
- profile_ptrace_perm(tracee, tracer,
- request << PTRACE_PERM_SHIFT,
- sa));
- /* policy uses the old style capability check for ptrace */
- if (profile_unconfined(tracer) || tracer == tracee)
+ return profile_ptrace_perm(tracer, tracee, request, sa);
+
+ /* profile uses the old style capability check for ptrace */
+ if (&tracer->label == tracee)
return 0;
aad(sa)->label = &tracer->label;
- aad(sa)->peer = &tracee->label;
+ aad(sa)->peer = tracee;
aad(sa)->request = 0;
aad(sa)->error = aa_capable(&tracer->label, CAP_SYS_PTRACE, 1);
@@ -115,10 +123,13 @@ static int cross_ptrace_perm(struct aa_profile *tracer,
int aa_may_ptrace(struct aa_label *tracer, struct aa_label *tracee,
u32 request)
{
+ struct aa_profile *profile;
+ u32 xrequest = request << PTRACE_PERM_SHIFT;
DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_PTRACE);
- return xcheck_labels_profiles(tracer, tracee, cross_ptrace_perm,
- request, &sa);
+ return xcheck_labels(tracer, tracee, profile,
+ profile_tracer_perm(profile, tracee, request, &sa),
+ profile_tracee_perm(profile, tracer, xrequest, &sa));
}