From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from layka.disroot.org (layka.disroot.org [178.21.23.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5197B41A794 for ; Tue, 6 Oct 2026 08:47:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.21.23.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791276438; cv=none; b=M7sd2Gwfo2HFfIguI+7xLa71mLCKbarKKjIqzEiufFzSBvgkYpapT6vhrzNP/REmHH5R6JhNvVXr4ENakALLr8V/zpTqT7E376t9yl7VjTrsWMYyXc9kQJ23X7ishq8oLjzUuyD9jBgKUxI9ylqrcN950WTlCMvRJ/irgZ4ONIM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791276438; c=relaxed/simple; bh=GjNxk0AeALHHWoiii/KFIeT9bYeY17SP6MHvcQJcWIw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=EneVhYWTldFlGZ40kzPlLtjU/MymezbsG8CKtTLoCbfcbxW0Scjo/HIfFCVteUkLMCVJqEgAvoduq7UGnYtpEQ3TNCkzmNgzU7jSJvhxet2R0fjVdNA+2endFAddY4gphIWXy3K9hvDdqAVDfisPKffpqpvGFsRmBlBtV6lLqD8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org; spf=pass smtp.mailfrom=disroot.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b=ZnBSlmg1; arc=none smtp.client-ip=178.21.23.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=disroot.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b="ZnBSlmg1" Received: from mail01.layka.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id 1145782A47; Tue, 06 Oct 2026 10:47:12 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id ctoJuRL-Fpnq; Tue, 6 Oct 2026 10:47:11 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1791276431; bh=GjNxk0AeALHHWoiii/KFIeT9bYeY17SP6MHvcQJcWIw=; h=From:To:Cc:Subject:Date; b=ZnBSlmg1M4AcIuZY3SSlR3Z1qc1SaqaVhva01ZcrlnIikUUiUdouNATLFkT7Bw3of WewppA+hZ31EGPXetxPNXONDkgeVV/i4sPebf/W2LHc0mRm5YzYXnG2lSJRXpec8bN uZ+4yQFFRxwpgKADxFKd2iD5a4NrqV3Fcpf/Vi3pdohhBbhrtQrCnCH7WLdtmRD8Jq G9dm6WKtgA0pr0xn8FE/u74hmcM1SDt4OoZjUG94xbicbC35WI7yLysE5LGTxwkpLC G+2+F0yJcIZlYWJ64fiYLIvP64Z4w6N83xBbsZXamoK6rfMtBaaIIAsfMxquD0MpUY ZnnwF/QE8Tbaw== From: Masoud Aghasi To: bpf@vger.kernel.org Cc: andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, memxor@gmail.com, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org, emil@etsalapatis.com, ihor.solodrai@linux.dev, leon.hwang@linux.dev, Masoud Aghasi Subject: [PATCH bpf v5 0/3] bpf: Fix incorrect handling of user flags by percpu map updates Date: Tue, 6 Oct 2026 09:46:01 +0100 Message-ID: <20261006084604.780456-1-maghasi@disroot.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit For BPF_MAP_TYPE_PERCPU_ARRAY map, bpf_percpu_array_update() is not considering the possibility of a combination of (BPF_NOEXIST, BPF_EXIST) flags with (BPF_F_CPU, BPF_F_ALL_CPUS) flags. This causes the (BPF_NOEXIST, BPF_EXIST) flags to lose their effect in some cases. For BPF_MAP_TYPE_PERCPU_HASH and BPF_MAP_TYPE_LRU_PERCPU_HASH maps, htab_map_check_update_flags() and check_flags() are not considering the possibility of a combination of (BPF_NOEXIST, BPF_EXIST) flags with (BPF_F_CPU, BPF_F_ALL_CPUS) flags. This causes the (BPF_NOEXIST, BPF_EXIST) flags to lose their effect in some cases. For example, when using (BPF_F_CPU | BPF_EXIST) flag combination with bpf_map_update_elem() on a BPF_MAP_TYPE_PERCPU_HASH map, the BPF_EXIST flag does not prevent new insertions as expected. This series fixes the bug by adding proper flag validations and checks and adds regression tests. V5 changes: - Simplify flag validations by introducing new macros in bpf.h - Add helpers to verify the values after updates in the new tests - Improve the style and structure of the new tests V4 changes: https://lore.kernel.org/bpf/20261004111007.3216186-1-maghasi@disroot.org/T/ - Edit selftest to use proper value_sz in the new cgroup map test - Edit selftest to pin the current pid to the current cpu for LRU map - Edit commit messages to include user-visible changes V3 changes: https://lore.kernel.org/bpf/20261003160213.2641506-1-maghasi@disroot.org/T/ - Split the fix into two separate patches for array map and hash maps - Extend the selftest to cover all percpu map types - Extend the selftest to cover all applicable flag combinations - Extend the selftest to cover the unnecessary delete issue of LRU map V2 changes: https://lore.kernel.org/bpf/20260930135753.1063495-1-maghasi@disroot.org/T/ - Fix a BPF_EXIST flag check in __htab_lru_percpu_map_update_elem() - Add additional test for BPF_MAP_TYPE_LRU_PERCPU_HASH map - Add check for BPF_EXIST, BPF_NOEXIST combination in percpu array map V1: https://lore.kernel.org/bpf/20260928102821.995214-1-maghasi@disroot.org/T/ Masoud Aghasi (3): bpf: Fix incorrect handling of user flags in bpf_percpu_array_update bpf: Fix incorrect handling of user flags by percpu hash map updates selftests/bpf: add tests for percpu map flags combination include/linux/bpf.h | 3 + kernel/bpf/arraymap.c | 6 +- kernel/bpf/hashtab.c | 10 +- .../selftests/bpf/prog_tests/percpu_alloc.c | 249 ++++++++++++++++++ 4 files changed, 261 insertions(+), 7 deletions(-) -- 2.47.3