From a4626e978677e3d3e816fdc217d8416c8b9462ae Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Wed, 23 Oct 2024 14:21:58 -0700 Subject: lsm: secctx provider check on release Verify that the LSM releasing the secctx is the LSM that allocated it. This was not necessary when only one LSM could create a secctx, but once there can be more than one it is. Signed-off-by: Casey Schaufler [PM: subject tweak] Signed-off-by: Paul Moore --- security/selinux/hooks.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 4f8d37ae769a..a2e72f1212a3 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6672,14 +6672,11 @@ static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) static void selinux_release_secctx(struct lsm_context *cp) { - /* - * stacking scaffolding: - * When it is possible for more than one LSM to provide a - * release hook, do this check: - * if (cp->id == LSM_ID_SELINUX || cp->id == LSM_ID_UNDEF) - */ - - kfree(cp->context); + if (cp->id == LSM_ID_SELINUX) { + kfree(cp->context); + cp->context = NULL; + cp->id = LSM_ID_UNDEF; + } } static void selinux_inode_invalidate_secctx(struct inode *inode) -- cgit v1.2.3