diff options
| author | John Johansen <john.johansen@canonical.com> | 2026-03-03 11:08:02 -0800 |
|---|---|---|
| committer | John Johansen <john.johansen@canonical.com> | 2026-03-09 16:05:43 -0700 |
| commit | 306039414932c80f8420695a24d4fe10c84ccfb2 (patch) | |
| tree | d2fedc885647c60d67b62a7d66a8cf437bae9657 /security | |
| parent | ab09264660f9de5d05d1ef4e225aa447c63a8747 (diff) | |
apparmor: fix: limit the number of levels of policy namespaces
Currently the number of policy namespaces is not bounded relying on
the user namespace limit. However policy namespaces aren't strictly
tied to user namespaces and it is possible to create them and nest
them arbitrarily deep which can be used to exhaust system resource.
Hard cap policy namespaces to the same depth as user namespaces.
Fixes: c88d4c7b049e8 ("AppArmor: core policy routines")
Reported-by: Qualys Security Advisory <qsa@qualys.com>
Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Reviewed-by: Cengiz Can <cengiz.can@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/apparmor/include/policy_ns.h | 2 | ||||
| -rw-r--r-- | security/apparmor/policy_ns.c | 2 |
2 files changed, 4 insertions, 0 deletions
diff --git a/security/apparmor/include/policy_ns.h b/security/apparmor/include/policy_ns.h index d646070fd966..cc6e84151812 100644 --- a/security/apparmor/include/policy_ns.h +++ b/security/apparmor/include/policy_ns.h @@ -18,6 +18,8 @@ #include "label.h" #include "policy.h" +/* Match max depth of user namespaces */ +#define MAX_NS_DEPTH 32 /* struct aa_ns_acct - accounting of profiles in namespace * @max_size: maximum space allowed for all profiles in namespace diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c index 01b653a3609b..5a907a875d8f 100644 --- a/security/apparmor/policy_ns.c +++ b/security/apparmor/policy_ns.c @@ -223,6 +223,8 @@ static struct aa_ns *__aa_create_ns(struct aa_ns *parent, const char *name, AA_BUG(!name); AA_BUG(!mutex_is_locked(&parent->lock)); + if (parent->level > MAX_NS_DEPTH) + return ERR_PTR(-ENOSPC); ns = alloc_ns(parent->base.hname, name); if (!ns) return ERR_PTR(-ENOMEM); |