From patchwork Thu Oct 24 10:40:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jordan Rome X-Patchwork-Id: 13848768 X-Patchwork-Delegate: paul@paul-moore.com Received: from mout.perfora.net (mout.perfora.net [74.208.4.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 437C414831C; Thu, 24 Oct 2024 10:54:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.208.4.197 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729767259; cv=none; b=rdAzDXI1IfDm6HldyHol3amaNy0jkVkiRhRQ7hnpCIpDEiVQ5svyTOE6etBqQAroRldir/Oop9PCtEihxvTYbC1AUgJOQQvwqGaQmKwhFO0qmI6h0t5lViujEDKK4oVwTiNdHap9II6zBmAPQ3NSD+9qGjo89wq6udmCKYL2L+E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729767259; c=relaxed/simple; bh=yGIhl8mYevvDwyWw0FFi2f+T/poFxSeXxHfTIzF4olA=; 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+ __entry->targ_ns = targ_ns; + __entry->capable_ns = capable_ns; + __entry->cap = cap; + __entry->opts = opts; + __entry->ret = ret; + ), + + TP_printk("cap %d, opts %u, ret %d", + __entry->cap, __entry->opts, __entry->ret) +); + +#endif /* _TRACE_CAPABILITY_H */ + +/* This part must be outside protection */ +#include diff --git a/security/commoncap.c b/security/commoncap.c index 162d96b3a676..675d40fbaa77 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -27,6 +27,9 @@ #include #include +#define CREATE_TRACE_POINTS +#include + /* * If a non-root user executes a setuid-root binary in * !secure(SECURE_NOROOT) mode, then we raise capabilities. @@ -68,6 +71,7 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, int cap, unsigned int opts) { struct user_namespace *ns = targ_ns; + int ret = 0; /* See if cred has the capability in the target user namespace * by examining the target user namespace and all of the target @@ -75,22 +79,26 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, */ for (;;) { /* Do we have the necessary capabilities? */ - if (ns == cred->user_ns) - return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; + if (ns == cred->user_ns) { + ret = cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; + break; + } /* * If we're already at a lower level than we're looking for, * we're done searching. */ - if (ns->level <= cred->user_ns->level) - return -EPERM; + if (ns->level <= cred->user_ns->level) { + ret = -EPERM; + break; + } /* * The owner of the user namespace in the parent of the * user namespace has all caps. */ if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) - return 0; + break; /* * If you have a capability in a parent user ns, then you have @@ -99,7 +107,8 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, ns = ns->parent; } - /* We never get here */ + trace_capable(cred, targ_ns, ret == 0 ? ns : NULL, cap, opts, ret); + return ret; } /**