From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 ED33D282F1E; Wed, 8 Apr 2026 18:15:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775672111; cv=none; b=g6YGDW4E/1X3hiBNkpUkICxWvTd2XFBzpH+LbnXvu7lJPRWGmqbP7WOmnigei3lf0G2Koy/u2rZgrZ0V7tnDQ+WFw74Go1vA2ea2ZRFXOKq+ES8PTJk5anlEA4yxeVAeyqgAxK8U8lrUzFvYv8XANjpY3BRcgkL6n0Gb+NJKX8o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775672111; c=relaxed/simple; bh=tWhJDnOMhU+ZSlAjW/KxwtQEML2TSxnHdQyreUOQJhY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=F1uk9yMA5kUPelOUbLIzpt1DQOi0ODlZ27NKfgYPPxWBmEn5EVdUuefyyy4FsLFOy1nqjorIjPPe+2TDyUUQ8r+ZMUbZkSTFHlyVI1pAE9CrlwsNiaDFKpID50LRDkeCKhQHubSCyEdvZA/2lTXO/6ULtiG3qpTNyqfDAdYpH8s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zgTmwIG0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zgTmwIG0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79E68C19421; Wed, 8 Apr 2026 18:15:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775672110; bh=tWhJDnOMhU+ZSlAjW/KxwtQEML2TSxnHdQyreUOQJhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zgTmwIG0e+VaDjQNTJhn2SRzpucm+qDbZGec+qDclinSIc71pk7t7A0kTBw14euxO m60kqIJ8tssTdG2Nto87FiHb9+HgAWEjkVR/g3DaVo3c8rcJ0ia+IYU39phHpvLx2j TUAljQTABfUKz7urXNt4fpuy95J2U5JzOniKh9rw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Amery Hung , Eduard Zingerman , Sasha Levin Subject: [PATCH 6.1 161/312] bpf: Fix regsafe() for pointers to packet Date: Wed, 8 Apr 2026 20:01:18 +0200 Message-ID: <20260408175939.778354654@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175933.715315542@linuxfoundation.org> References: <20260408175933.715315542@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexei Starovoitov [ Upstream commit a8502a79e832b861e99218cbd2d8f4312d62e225 ] In case rold->reg->range == BEYOND_PKT_END && rcur->reg->range == N regsafe() may return true which may lead to current state with valid packet range not being explored. Fix the bug. Fixes: 6d94e741a8ff ("bpf: Support for pointers beyond pkt_end.") Signed-off-by: Alexei Starovoitov Signed-off-by: Andrii Nakryiko Reviewed-by: Daniel Borkmann Reviewed-by: Amery Hung Acked-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260331204228.26726-1-alexei.starovoitov@gmail.com Signed-off-by: Sasha Levin --- kernel/bpf/verifier.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 74c56ed5ddcbb..59f53fea9e3c6 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -11832,8 +11832,13 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, * since someone could have accessed through (ptr - k), or * even done ptr -= k in a register, to get a safe access. */ - if (rold->range > rcur->range) + if (rold->range < 0 || rcur->range < 0) { + /* special case for [BEYOND|AT]_PKT_END */ + if (rold->range != rcur->range) + return false; + } else if (rold->range > rcur->range) { return false; + } /* If the offsets don't match, we can't trust our alignment; * nor can we be sure that we won't fall out of range. */ -- 2.53.0