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 3FDED2D3FB4; Tue, 29 Apr 2025 23:53:13 +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=1745970793; cv=none; b=SkrcRoZ8ItDPzRBp1WUy4rHlxo3G0tr60P7GTc0zgPOg5z8EFEB1pp6ZVjesCQkQEPKdwjZiy0cwlo48DHI1OTAzKonSzATPHAhgxw9AwfT1glF4E/XGC5pqCyER1HQJJ3VQ/LNxGFFnqD1tUOyIm+1N/IFOnadxOxqxbzm2lsw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745970793; c=relaxed/simple; bh=CfWOt/JjFOfExcRczY+gftfEH2MEXx9odLS3CtWyd/4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fbc2UFvYrRDfY12NcRu2i9ZCGE1LB8zykGmBcOq3IKM5FAhbDuY2F2NOoKCiAcbLLpF+jsAncwXq0oYGYXUffcv9F+MB9ZiVSymLwLs65H7/JE+bT3P6xbNojXwbpYyXgnQ2uXsMM4EAcT9f4ml9JljNM828UtxK9PuSmCi7dvw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=idFuLsQq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="idFuLsQq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19889C4CEE3; Tue, 29 Apr 2025 23:53:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745970793; bh=CfWOt/JjFOfExcRczY+gftfEH2MEXx9odLS3CtWyd/4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=idFuLsQqQfwfGKvueEsX38MOzQV3YhguVcidThehp4Wd3BJCDJHIgLWy4pi2s9cnp fmNsxEX4bD82lEZYQyOSPmvtdaSSAEwT4KJHbDawd34cjxSP5Z4VY+Jb2Ml1BZTrMS FSFnS3SXD5aoH64gI1DDp5gBMWgc+WPddI2TX+OvpP2B+26RmZCNZskklmiSKmTP1E ujUW2q54moyjIqJkmVc5gtYh9y8GTfS0EF7oN65a5uQmsDMkbE0PJ49/2Eh82lNQG9 sofD+iLTyquUgBn7CsE9t+wJt6uTjO7QPEf934ILPLXOzA9PEb+xoEyhQGx8Qr/bbV jdpN9nRGcyrMg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Brandon Kammerdiener , Alexei Starovoitov , Hou Tao , Sasha Levin , daniel@iogearbox.net, andrii@kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 20/21] bpf: fix possible endless loop in BPF map iteration Date: Tue, 29 Apr 2025 19:52:32 -0400 Message-Id: <20250429235233.537828-20-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250429235233.537828-1-sashal@kernel.org> References: <20250429235233.537828-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.88 Content-Transfer-Encoding: 8bit From: Brandon Kammerdiener [ Upstream commit 75673fda0c557ae26078177dd14d4857afbf128d ] The _safe variant used here gets the next element before running the callback, avoiding the endless loop condition. Signed-off-by: Brandon Kammerdiener Link: https://lore.kernel.org/r/20250424153246.141677-2-brandon.kammerdiener@intel.com Signed-off-by: Alexei Starovoitov Acked-by: Hou Tao Signed-off-by: Sasha Levin --- kernel/bpf/hashtab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index fc34f72702cc4..8a3eadf17f785 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -2212,7 +2212,7 @@ static long bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_ b = &htab->buckets[i]; rcu_read_lock(); head = &b->head; - hlist_nulls_for_each_entry_rcu(elem, n, head, hash_node) { + hlist_nulls_for_each_entry_safe(elem, n, head, hash_node) { key = elem->key; if (is_percpu) { /* current cpu value for percpu map */ -- 2.39.5