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 8D5FA2D8180; Tue, 29 Apr 2025 23:53:36 +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=1745970816; cv=none; b=U3Yp5aJRJx4YtdMQlBnCw1V8jUq/Xza6orOf/rBnh46XUYPFVxJubZBsp9MDh6puU1LdgMf0biPYQc1N67cDEdxxXxQkJ01wGJhkOE2t4PFaZNdXHAWjSV7v0FIj6rM7aRYj0eGJkqkIceTd3ZeBX0zgbtP2aRLcRF+li7G05r0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745970816; c=relaxed/simple; bh=JKbRXcJvcvMSucEBBYME5qE9RmdEOPa9o6s6mQCt+50=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=aDCW+kshBa6gsuRw2V02lUSzalaWUnoeDMsTXodfKI+aPz+vpEuABw23D4evE83x/DXCTLUZurqqgXMsNZpqbUTRkcW4b66LcSt8e6veBUhgzwHaYN5zF7NWt7AW+cp3Q9KfmSFScgCELhyP030OESiqzG4PASKOtoO6txVjF4o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XQLLAUD2; 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="XQLLAUD2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3F4DC4CEEB; Tue, 29 Apr 2025 23:53:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745970816; bh=JKbRXcJvcvMSucEBBYME5qE9RmdEOPa9o6s6mQCt+50=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XQLLAUD22bCRBu0wLtNtPrABmoixRhBeoCDWS5tRrRRuNEa0W4jYF2UiWGivgCP7O V3t1X7/Ewkj7xZAdB0Vvx0MHCUzjGnWQxeJr0xg6tUzwCnIMyEQ/UMWnOwiYn9KCAS EhFI5Tvb4DO9+wVA3UFlLf6NvOPomBr0MZsNdl8Vt2piqlkUvzCY08GxHjdEUVUnm7 mwSiI4zEjuvdATm88Ts5klBzgdsBv/A7eVSmC3p/BJR3nU5fciceQQFCnki//S+ZSD 3/UuyTOQqJRiNxUc3MDN5YytcJI52fplKIDbL/eY3bIilCvCXhwVJ7tNsKxWCN1zEK ZNtObY/72rqVg== 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 6.1 09/10] bpf: fix possible endless loop in BPF map iteration Date: Tue, 29 Apr 2025 19:53:14 -0400 Message-Id: <20250429235316.538129-9-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250429235316.538129-1-sashal@kernel.org> References: <20250429235316.538129-1-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 6.1.135 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 dae9ed02a75be..06bc7f26be06f 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -2172,7 +2172,7 @@ static int bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_f 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