From: Vratislav Bendel <vbendel@xxxxxxxxxx> commit 186edf7e368c40d06cf727a1ad14698ea67b74ad upstream. On error path from cond_read_list() and duplicate_policydb_cond_list() the cond_list_destroy() gets called a second time in caller functions, resulting in NULL pointer deref. Fix this by resetting the cond_list_len to 0 in cond_list_destroy(), making subsequent calls a noop. Also consistently reset the cond_list pointer to NULL after freeing. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Vratislav Bendel <vbendel@xxxxxxxxxx> [PM: fix line lengths in the description] Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- security/selinux/ss/conditional.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -152,6 +152,8 @@ static void cond_list_destroy(struct pol for (i = 0; i < p->cond_list_len; i++) cond_node_destroy(&p->cond_list[i]); kfree(p->cond_list); + p->cond_list = NULL; + p->cond_list_len = 0; } void cond_policydb_destroy(struct policydb *p) @@ -440,7 +442,6 @@ int cond_read_list(struct policydb *p, v return 0; err: cond_list_destroy(p); - p->cond_list = NULL; return rc; } Patches currently in stable-queue which might be from vbendel@xxxxxxxxxx are queue-5.10/selinux-fix-double-free-of-cond_list-on-error-paths.patch