From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yx1-f53.google.com (mail-yx1-f53.google.com [74.125.224.53]) (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 4A5AC275B1A for ; Mon, 20 Apr 2026 20:34:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.224.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776717256; cv=none; b=XGKH9HrDJwGfjlULuwsUacvKiyQGzgIDlC9DLKtDZLTQ8lUK6RayJ7hW8IjTUsS65JRkXAOV+/aa7bdyJAtW/oWHNHDHRgXyJ6wlmBU8NbqLZQ86qxcS7K9TxE4UKj+/YRnfGzP16JPk1CvZWh1teLotnJGYz3l3PIGhzyIEWSo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776717256; c=relaxed/simple; bh=PDqeiom2m+MSqld0lQIyBc5Sao/iUUWTvj2TcJ7JiOM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=lY4tGdFtpoR+EaZ9jjWng2sg4lUss/lXu7rRYzCL6tFaYudslocItrS7YEC1WTj1L1PFFXvxCDPk6s2IBdtX+D5KxW7cqTOUqgdf22+tHsGIXebv4vUMxnOeWuQXqYr6hY5uyOaNcMMO8LHcCSGd4FRbnyxubmPDZaiNu7BdzrY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=UQ0duuNA; arc=none smtp.client-ip=74.125.224.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="UQ0duuNA" Received: by mail-yx1-f53.google.com with SMTP id 956f58d0204a3-65075c2ba66so2203384d50.1 for ; Mon, 20 Apr 2026 13:34:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1776717254; x=1777322054; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=IDx3Ks3i/24PrFwCTkn8aAiTFZamVdc9q4/U3VM8mfw=; b=UQ0duuNACshfiEDlq1Zn82TfTtPWqNezP/0p1VwYXhXA3XrV6IRbJ/sLnNHE+KzCvH zVqivXlBh+fwc/U17sxZkHpiq586DfgSRMJf2ICQcRf6nSCh/8RQjD0waOg32BlKO38B 10LIP6a8OeiBlbLpPsWBdGybDz4HPtKUdIS+nM3C4PKT5bhVo2OiAr/x6T0z0U0v/yIo RTtIYki1ohXLjzyq625VuRjsMl6SXXGvw3bEU87q4plt4uAByIpADuWjmI5eUHvSSdtp 6wjfRxRYeuf3BZM5yYQUbqTNPNSUHA3rpOCjHpoJC4iR/PaGZJWGQ1/vFOfz9ljix47G htJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776717254; x=1777322054; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=IDx3Ks3i/24PrFwCTkn8aAiTFZamVdc9q4/U3VM8mfw=; b=ba1jXfwaQpbmhgrs2XtPYmToLpgun+EI/uyl97JmKPxMif3ckrDU0AUzl/OZTazmSA i4kLlsKkdisIuliIZ8vNKVt/XeomyfsUKhzxlgUOazDc3hVA0r6md6BCP3+LjUUiRhS2 50q1RKTrLlzW8zrWMll4I69uVLB2M1nrCVSMyUMsiAirkJmPxWLYuaWxEqtdPOpDXr2z cGqsI23NnNN9MZYOXyDv4+yOkuPcJC1MThkDwUylbK+pmlYVe1Wg6EYHIHqT4wv+wDaB wr+vkFoWSyoG/k/RZASha2ikfdox2yvkLG/tR3vHKyh2ZqyPZ1rqPEtl8eBdJn8fwe4o w0rw== X-Forwarded-Encrypted: i=1; AFNElJ8xJUYOGhYTMyDTF4CPexzdgIcG6R0CcKOzBhVweGVg78+lrZqv1xnhm3Rjykznhs1dOtQ=@vger.kernel.org X-Gm-Message-State: AOJu0Yw/rYKU5xRGwSeFbY1X9o/Sk5+gst1qBIKuYwk+HzTUNdPA7P4n KB2tfd11hpbIkIS0N7oeBwaRlt7+UISS4w9d7dDEwt1luh+vO2U/Jqqb X-Gm-Gg: AeBDieuAcEhKZkWUNi9kG3PotnvKKZdWvH2HTNsDrJM5Cr0679KvYtiCFiUGzkXThHK 1JX5gzSh0TcZJmVK01/MwPpnZIcptf8Ld039yfr+b6IWELENakCA6sOuEdGiOtj+lrnR6tIzBoR MpjOg693e3YrodAxYyn//hzkK+B0jDKFvRIj93l4WWDonwGlkGge3HrWCmgfx7w+7Y6AzmkK8Oj MF2NHkaEpXxDYimMDe5gcsJlgwS2LsmlS4x/B+B5m6cSiOqyg9XrF3fCqxlH/WHEcpwZaklAI/q nq4CQPHnncsFV/9eDcjK1Usoz25LMHu0CvHrO427IIKiEi/HenAk8Rz+PnhJNuZYxLRKXbyw/s6 ggfm1NH3Fo6hOB3NqvHk8Et4GX/dvSQkWQrY3zJ9faHmJRDijKTQDX0jXTj0WdDbe4k7cGOllun mFpU21zuSMCwJk79gJpic/LteyqBDMHCYEZqpItkTtBHjzUhPYIfntrvoyebEFKKNnL02y7Ioyt xKU3R5KOVI= X-Received: by 2002:a05:690e:484e:b0:653:f75:b7aa with SMTP id 956f58d0204a3-653107e2044mr9666234d50.13.1776717254224; Mon, 20 Apr 2026 13:34:14 -0700 (PDT) Received: from zenbox.prizrak.me ([2600:1700:18fb:6011:adde:1cbf:87f2:a99c]) by smtp.gmail.com with ESMTPSA id 956f58d0204a3-65314e81399sm5702955d50.14.2026.04.20.13.34.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2026 13:34:13 -0700 (PDT) From: Justin Suess To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, memxor@gmail.com Cc: martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org, bpf@vger.kernel.org, mic@digikod.net, Justin Suess Subject: [PATCH bpf-next 0/2] Allow storing referenced struct file kptrs in BPF maps Date: Mon, 20 Apr 2026 16:33:04 -0400 Message-ID: <20260420203306.3107246-1-utilityemal77@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello, This series adds a destructor for struct file, enabling it to be used as a referenced kptr in BPF maps. The destructor mirrors bpf_put_file() semantics and releases the reference via fput(). This allows pointers returned from kfuncs such as bpf_get_task_exe_file() to be safely stored and later reused with helpers and kfuncs that operate on struct file. This fills a gap compared to bpf_dynptr_from_file(), where the resulting dynptr can be stored in a map, but cannot be passed to kfuncs expecting a struct file *. Use cases include caching file references across events and deferring processing while keeping the underlying file alive. Patch 1 adds the struct file kptr destructor and wires it into the BTF kfunc sets. Patch 2 adds selftests covering successful use and verifier rejection of unreferenced pointers. Justin Suess (2): bpf: Implement dtor for struct file BTF ID selftests/bpf: Add test for map-stored struct file kptrs kernel/bpf/helpers.c | 16 +- .../bpf/prog_tests/refcounted_kptr_file.c | 246 ++++++++++++++++++ .../bpf/progs/refcounted_kptr_file.c | 152 +++++++++++ .../bpf/progs/refcounted_kptr_file_fail.c | 35 +++ 4 files changed, 448 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/refcounted_kptr_file.c create mode 100644 tools/testing/selftests/bpf/progs/refcounted_kptr_file.c create mode 100644 tools/testing/selftests/bpf/progs/refcounted_kptr_file_fail.c -- 2.53.0