kernel/git/next/linux-next.git/security/apparmor/policy.c, branch stable

apparmor: fix label can not be immediately before a declaration

2026-06-15T01:22:35+00:00

Fix error reported by kernel test robot security/apparmor/policy.c:1381:2: error: a label can only be part of a statement and a declaration is not a statement All errors (new ones prefixed by >>): security/apparmor/policy.c: In function 'aa_replace_profiles': >> security/apparmor/policy.c:1381:2: error: a label can only be part of a statement and a declaration is not a statement ssize_t udata_sz = udata->size; ^~~~~ Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202606150525.npax8WiH-lkp@intel.com/ Fixes: 7b42f95813dc9 ("apparmor: fix potential UAF in aa_replace_profiles") Signed-off-by: John Johansen

apparmor: fix use-after-free in rawdata dedup loop

2026-06-14T03:20:13+00:00

aa_replace_profiles() walks ns->rawdata_list to dedup the incoming policy blob against entries already attached to existing profiles. Per the kernel-doc on struct aa_loaddata, list membership does not hold a reference: profiles hold pcount, and when the last pcount drops, do_ploaddata_rmfs() is queued on a workqueue that takes ns->lock and removes the entry. Between dropping the last pcount and the workqueue running, an entry remains on the list with pcount == 0. aa_get_profile_loaddata() is an unconditional kref_get() on pcount, so when the dedup loop hits such an entry, refcount hardening reports refcount_t: addition on 0; use-after-free. inside aa_replace_profiles(), and the poisoned counter then trips "saturated" and "underflow" warnings on the subsequent uses of the same loaddata. Before commit a0b7091c4de4 ("apparmor: fix race on rawdata dereference") the dedup path used a get_unless_zero-style helper on a single counter, so the existing "if (tmp)" guard was meaningful. The split-refcount refactor introduced aa_get_profile_loaddata(), which has plain kref_get() semantics, and the guard quietly became a no-op. Introduce aa_get_profile_loaddata_not0(), matching the existing _not0 convention used by aa_get_profile_not0(), and use it for the rawdata_list dedup lookup so dying entries are skipped. Reproduced on x86_64 with v7.1-rc5 in QEMU+KVM running Ubuntu 24.04 + stress-ng 0.17.06: stress-ng --apparmor 1 --klog-check --timeout 60s Without this patch the three refcount_t warnings fire within a few seconds. With it the same 60 s run is clean. Coverage is a smoke-test only; a longer soak with CONFIG_KASAN, CONFIG_KCSAN and CONFIG_PROVE_LOCKING would be welcome from anyone with the cycles. Fixes: a0b7091c4de4 ("apparmor: fix race on rawdata dereference") Reported-by: Colin Ian King Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221513 Cc: stable@vger.kernel.org Signed-off-by: Ruslan Valiyev Signed-off-by: John Johansen

apparmor: remove or add symlinks to rawdata according to export_binary

2026-06-14T03:14:07+00:00

When the export_binary parameter is set, then rawdata is available and there should be a symbolic link for the rawdata in the profile directory in apparmorfs. If the parameter is unset, then the symlinks should not exist. The issue arises when changing the value of export_binary on runtime and replacing profiles. If export_binary was set when the profile was originally loaded, then changed to 0 and the profile was reloaded, then the symbolic links would still exist but would return ENOENT because the rawdata no longer exists. On the opposite side, if export_binary was unset when the profile was originally loaded, then changed to 1 and the profile was reloaded, then the symbolic links would not exist, even though the rawdata does. Fixes: d61c57fde8191 ("apparmor: make export of raw binary profile to userspace optional") Signed-off-by: Georgia Garcia Signed-off-by: John Johansen

apparmor: fix potential UAF in aa_replace_profiles

2026-06-14T03:14:07+00:00

The function aa_replace_profiles was accessing udata->size after calling aa_put_loaddata(udata), causing a potential UAF. Fixed this by saving the size to a local variable before dropping the reference. Fixes: 5ac8c355ae001 ("apparmor: allow introspecting the loaded policy pre internal transform") Reviewed-by: Georgia Garcia Signed-off-by: Maxime Bélair Signed-off-by: John Johansen

apparmor: free rawdata as soon as possible

2026-06-14T03:14:07+00:00

profiles can be pinned by file and other references, and can live long after they have been replaced/removed. The rawdata however is no longer needed, and can be freed earlier than the rest of the profile. Reviewed-by: Georgia Garcia Signed-off-by: John Johansen

apparmor: fix race on rawdata dereference

2026-03-09T23:05:44+00:00

There is a race condition that leads to a use-after-free situation: because the rawdata inodes are not refcounted, an attacker can start open()ing one of the rawdata files, and at the same time remove the last reference to this rawdata (by removing the corresponding profile, for example), which frees its struct aa_loaddata; as a result, when seq_rawdata_open() is reached, i_private is a dangling pointer and freed memory is accessed. The rawdata inodes weren't refcounted to avoid a circular refcount and were supposed to be held by the profile rawdata reference. However during profile removal there is a window where the vfs and profile destruction race, resulting in the use after free. Fix this by moving to a double refcount scheme. Where the profile refcount on rawdata is used to break the circular dependency. Allowing for freeing of the rawdata once all inode references to the rawdata are put. Fixes: 5d5182cae401 ("apparmor: move to per loaddata files, instead of replicating in profiles") Reported-by: Qualys Security Advisory Reviewed-by: Georgia Garcia Reviewed-by: Maxime Bélair Reviewed-by: Cengiz Can Tested-by: Salvatore Bonaccorso Signed-off-by: John Johansen

apparmor: fix unprivileged local user can do privileged policy management

2026-03-09T23:05:43+00:00

An unprivileged local user can load, replace, and remove profiles by opening the apparmorfs interfaces, via a confused deputy attack, by passing the opened fd to a privileged process, and getting the privileged process to write to the interface. This does require a privileged target that can be manipulated to do the write for the unprivileged process, but once such access is achieved full policy management is possible and all the possible implications that implies: removing confinement, DoS of system or target applications by denying all execution, by-passing the unprivileged user namespace restriction, to exploiting kernel bugs for a local privilege escalation. The policy management interface can not have its permissions simply changed from 0666 to 0600 because non-root processes need to be able to load policy to different policy namespaces. Instead ensure the task writing the interface has privileges that are a subset of the task that opened the interface. This is already done via policy for confined processes, but unconfined can delegate access to the opened fd, by-passing the usual policy check. Fixes: b7fd2c0340eac ("apparmor: add per policy ns .load, .replace, .remove interface files") Reported-by: Qualys Security Advisory Tested-by: Salvatore Bonaccorso Reviewed-by: Georgia Garcia Reviewed-by: Cengiz Can Signed-off-by: John Johansen

apparmor: Fix double free of ns_name in aa_replace_profiles()

2026-03-09T23:05:43+00:00

if ns_name is NULL after 1071 error = aa_unpack(udata, &lh, &ns_name); and if ent->ns_name contains an ns_name in 1089 } else if (ent->ns_name) { then ns_name is assigned the ent->ns_name 1095 ns_name = ent->ns_name; however ent->ns_name is freed at 1262 aa_load_ent_free(ent); and then again when freeing ns_name at 1270 kfree(ns_name); Fix this by NULLing out ent->ns_name after it is transferred to ns_name Fixes: 145a0ef21c8e9 ("apparmor: fix blob compression when ns is forced on a policy load ") Reported-by: Qualys Security Advisory Tested-by: Salvatore Bonaccorso Reviewed-by: Georgia Garcia Reviewed-by: Cengiz Can Signed-off-by: John Johansen

apparmor: replace recursive profile removal with iterative approach

2026-03-09T23:05:42+00:00

The profile removal code uses recursion when removing nested profiles, which can lead to kernel stack exhaustion and system crashes. Reproducer: $ pf='a'; for ((i=0; i<1024; i++)); do echo -e "profile $pf { \n }" | apparmor_parser -K -a; pf="$pf//x"; done $ echo -n a > /sys/kernel/security/apparmor/.remove Replace the recursive __aa_profile_list_release() approach with an iterative approach in __remove_profile(). The function repeatedly finds and removes leaf profiles until the entire subtree is removed, maintaining the same removal semantic without recursion. Fixes: c88d4c7b049e ("AppArmor: core policy routines") Reported-by: Qualys Security Advisory Tested-by: Salvatore Bonaccorso Reviewed-by: Georgia Garcia Reviewed-by: Cengiz Can Signed-off-by: Massimiliano Pellizzer Signed-off-by: John Johansen

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook