kernel/linux.git/security/selinux, branch v6.18.33

selinux: prune /sys/fs/selinux/user

2026-05-14T13:30:14+00:00

commit ad1ac3d740cc6b858a99ab9c45c8c0574be7d1d3 upstream. Remove the previously deprecated /sys/fs/selinux/user interface aside from a residual stub for userspace compatibility. Commit d7b6918e22c7 ("selinux: Deprecate /sys/fs/selinux/user") started the deprecation process for /sys/fs/selinux/user: The selinuxfs "user" node allows userspace to request a list of security contexts that can be reached for a given SELinux user from a given starting context. This was used by libselinux when various login-style programs requested contexts for users, but libselinux stopped using it in 2020. Kernel support will be removed no sooner than Dec 2025. A pr_warn() message has been in place since Linux v6.13, and a 5 second sleep was introduced since Linux v6.17 to help make it more noticeable. We are now past the stated deadline of Dec 2025, so remove the underlying functionality and replace it with a stub that returns a '0\0' buffer to avoid breaking userspace. This also avoids a local DoS from logspam and an uninterruptible sleep delay. Cc: stable@vger.kernel.org Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: prune /sys/fs/selinux/disable

2026-05-14T13:30:14+00:00

commit 19cfa0099024bb9cd40f6d950caa7f47ff8e77f6 upstream. Commit f22f9aaf6c3d ("selinux: remove the runtime disable functionality") removed the underlying SELinux runtime disable functionality but left everything else intact and started logging an error message to warn any residual users. Prune it to just log an error message once and to return count (i.e. all bytes written successfully) to avoid breaking userspace. This also fixes a local DoS from logspam. Cc: stable@vger.kernel.org Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: prune /sys/fs/selinux/checkreqprot

2026-05-14T13:30:14+00:00

commit 644132a48f4e28a1d949d162160869286f3e75de upstream. commit a7e4676e8e2cb ("selinux: remove the 'checkreqprot' functionality") removed the ability to modify the checkreqprot setting but left everything except the updating of the checkreqprot value intact. Aside from unnecessary processing, this could produce a local DoS from log spam and incorrectly calls selinux_ima_measure_state() on each write even though no state has changed. Prune it to just log an error message once and return count (i.e. all bytes written successfully) so that userspace never breaks. Cc: stable@vger.kernel.org Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: shrink critical section in sel_write_load()

2026-05-14T13:30:14+00:00

commit 868f31e4061eca8c3cd607d79d954d5e54f204aa upstream. Currently sel_write_load() takes the policy mutex earlier than necessary. Move the taking of the mutex later. This avoids holding it unnecessarily across the vmalloc() and copy_from_user() of the policy data. Cc: stable@vger.kernel.org Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: don't reserve xattr slot when we won't fill it

2026-05-14T13:30:14+00:00

commit 1e5a8eed7821e7a43a31b4c1b3675a91be6bc6f6 upstream. Move lsm_get_xattr_slot() below the SBLABEL_MNT check so we don't leave a NULL-named slot in the array when returning -EOPNOTSUPP; filesystem initxattrs() callbacks stop iterating at the first NULL ->name, silently dropping xattrs installed by later LSMs. Cc: stable@vger.kernel.org Signed-off-by: David Windsor Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: use sk blob accessor in socket permission helpers

2026-05-14T13:30:14+00:00

commit 032e70aff025d7c519af9ab791cd084380619263 upstream. SELinux socket state lives in the composite LSM socket blob. sock_has_perm() and nlmsg_sock_has_extended_perms() currently dereference sk->sk_security directly, which assumes the SELinux socket blob is at offset zero. In stacked configurations that assumption does not hold. If another LSM allocates socket blob storage before SELinux, these helpers may read the wrong blob and feed invalid SID and class values into AVC checks. Use selinux_sock() instead of accessing sk->sk_security directly. Fixes: d1d991efaf34 ("selinux: Add netlink xperm support") Cc: stable@vger.kernel.org # v6.13+ Signed-off-by: Zongyao Chen Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: fix avdcache auditing

2026-05-14T13:30:14+00:00

commit f92d542577db878acfd21cc18dab23d03023b217 upstream. The per-task avdcache was incorrectly saving and reusing the audited vector computed by avc_audit_required() rather than recomputing based on the currently requested permissions and distinguishing the denied versus allowed cases. As a result, some permission checks were not being audited, e.g. directory write checks after a previously cached directory search check. Cc: stable@vger.kernel.org Fixes: dde3a5d0f4dce ("selinux: move avdcache to per-task security struct") Signed-off-by: Stephen Smalley [PM: line wrap tweaks] Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: rename the cred_security_struct variables to "crsec"

2025-11-20T21:47:50+00:00

Along with the renaming from task_security_struct to cred_security_struct, rename the local variables to "crsec" from "tsec". This both fits with existing conventions and helps distinguish between task and cred related variables. No functional changes. Acked-by: Stephen Smalley Signed-off-by: Paul Moore

selinux: move avdcache to per-task security struct

2025-11-20T21:43:51+00:00

The avdcache is meant to be per-task; move it to a new task_security_struct that is duplicated per-task. Cc: stable@vger.kernel.org Fixes: 5d7ddc59b3d89b724a5aa8f30d0db94ff8d2d93f ("selinux: reduce path walk overhead") Signed-off-by: Stephen Smalley [PM: line length fixes] Signed-off-by: Paul Moore

selinux: rename task_security_struct to cred_security_struct

2025-11-20T21:43:50+00:00

Before Linux had cred structures, the SELinux task_security_struct was per-task and although the structure was switched to being per-cred long ago, the name was never updated. This change renames it to cred_security_struct to avoid confusion and pave the way for the introduction of an actual per-task security structure for SELinux. No functional change. Cc: stable@vger.kernel.org Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore