From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (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 B1F643AD53C for ; Thu, 2 Apr 2026 09:29:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775122181; cv=none; b=E0+NDhRFU9Sky3RMALRF8Gh+ec0CxVS/vrEXKr48fS/2p6coFCbkqncNzdPei+/maZF8QoSrKblj2gbABV3+qcO5YNCFqjfWPZpruNRudrgzNDZSDQv2Xz5hybzlrkmUbWxcg+93xjFTQh2cShaEjvJD3iqlBRxhY10SBdpcWB0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775122181; c=relaxed/simple; bh=tSA+o9FDa78WsmD3iH+sl7pAYTRdnd1kK9FVuy5t8oM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=fVU18tRaJ4xYpZuGBOtQ1D1sCc9I3lgvEg6qBa/mA0RnsLbqosX23abmuwL5whUruAdpo3C73EdZwuOrymoWOmQF4jqRN7d69xaizNP0cxIZptZTENgXDm4ooZ8rAoLlKhhFxSLmp7P7/SzkHIbrCZCsDgFker7/yuLCLYe8v+M= 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=L4aIYRtI; arc=none smtp.client-ip=209.85.214.171 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="L4aIYRtI" Received: by mail-pl1-f171.google.com with SMTP id d9443c01a7336-2b2469e5117so3426645ad.1 for ; Thu, 02 Apr 2026 02:29:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1775122171; x=1775726971; 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=yLbzVc7f4E1BciqJ3cOYBXmu4dEWArxjVAddgytIGt4=; b=L4aIYRtIqyKJYIUh0n+c0FsQ0b8ylWIhfVV94As+pADkzg85Lc/xxyeKCkieWwHEWT im07ZEzoOsD1bkuUtstck1pw/j6FfI17s/0LM3Zq8h0pOKqTrB/1VhZLRdUQxrlXxj8Q qxuY0zbK5vDvnthLalthtY039Z7dJiicVIOLiJFg3OzgpMOOYJeOv6DhKfyDTbbGM8c/ wvPgPhM7IB4RQnRNbVj8X3JP/mNf8I4Eakb6+paenAz1KLnsSsxthvXFBOoy3QFuafKe svyrgHSyrRWlLrZdiuvKzENLEY5gwxxpLvBJ+ucOmYImxfEbo/0Ch4uILU7Ww6lNC3Id GGQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775122171; x=1775726971; 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=yLbzVc7f4E1BciqJ3cOYBXmu4dEWArxjVAddgytIGt4=; b=DRokaj+Mc/8Ig2RL89g5YBqbILJxCUcUaCpQCx2s5PvGDja3vMdkeC1XCKk6nGd5QF L+5BdNbYDIm4nT3KtxQ671cNijEXOQi4v7EUDHtweLzVN+/V0FS4NCoNV9aiLikOseo+ 5B/fVVw5odrsQWVvZJIwGFngig1IfOVDrIiY691vQGC2ge1eZvlLtZlUL2uIAKPguMbY aBBQICq5rtQesqF3N8FBArlwnDZxPf2GIHajWjUsHBZGD4rdczwMcQBuUXgeVNcoyjDI kV3vR/cMDWFzCYEnxWynjBa2TBzRQ+DsqhusDbHj9fsqawFzJQVjNJKahsUBPg5uHYbW mnpw== X-Forwarded-Encrypted: i=1; AJvYcCU6A6E6WQzx4/g6OQwrMpvh76yJEF6inbxwtS0A0jsOt/HATjG/UL0J3RadELu/UyMy+2A=@vger.kernel.org X-Gm-Message-State: AOJu0YwLYiAx/aW3u2aMNodFHAYu3508FFeCe2nw1shNiOlTh3SBnm5+ E0W/E/jVfLjY1jlKRK1da1B/AQPjPWioaSd5NTXNBsL3RrygxwT8kFAE X-Gm-Gg: AeBDietrjWWI8g63u94yb733YY6NNpU06ZbeYpNi/KKbx/x7fBbXQ1WxzOlpH5I99Ty pGyjjfLk8Mi0qPNCf/w+3kGr5v3PLMGrsiKiZ6sHX+kigjRpLcoixifPYog7u7blJbNigB5fyTN wUKOBsJLbT0AQo9nUVdC0lnbXg8nqYJAdLTxs8v43NzgBAOZtVVtE/jK81XZ8prNJpQMFsaUZs6 fPsPwL9xOFXnurQJvPZ4CoCWOW/kGZtINgAYWmEzIJojKgZtPEu+HNFgISCkgzVOY3pYMwdt9aK xXWAuMlQWaWGgjLWNC2k2zL0a7tEEKMnOywHZqFcRBzHiEtFXGLK3s5iQmt4Rq2C2dtZ9nyvW1U fUtz1wmr3oDcD7QeH4tLxGZ7VFppzWpbHvNdRE/vHNyoRolrYZYTBBUM7PkUDhEPeHBpfL3mQDR rMPdSXl9Y0F6VFhXvuQ/vwh79RrD9hpngH4vg= X-Received: by 2002:a17:902:d2ca:b0:2b0:b557:6fe5 with SMTP id d9443c01a7336-2b277e88764mr17140125ad.30.1775122170878; Thu, 02 Apr 2026 02:29:30 -0700 (PDT) Received: from localhost.localdomain ([47.236.127.140]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b2749cada2sm21176705ad.71.2026.04.02.02.29.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Apr 2026 02:29:30 -0700 (PDT) From: Qi Tang To: Alexei Starovoitov , Daniel Borkmann Cc: Eduard Zingerman , Andrii Nakryiko , Martin KaFai Lau , John Fastabend , Song Liu , bpf@vger.kernel.org, Qi Tang Subject: [PATCH bpf v3 0/2] bpf: reject direct access to nullable PTR_TO_BUF pointers Date: Thu, 2 Apr 2026 17:29:21 +0800 Message-ID: <20260402092923.38357-1-tpluszz77@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit check_mem_access() allows direct dereference of PTR_TO_BUF | PTR_MAYBE_NULL without a null check, causing kernel NULL dereference on map iterator stop callbacks. Patch 1 adds the missing type_may_be_null() guard. Patch 2 adds a selftest. Changes in v3: - Drop stack trace from commit log - Split kernel fix and selftest into separate patches - Use [PATCH bpf] prefix Changes in v2: - Add selftest Link: https://lore.kernel.org/all/20260401142316.2452-1-tpluszz77@gmail.com/ (v2) Link: https://lore.kernel.org/all/20260331172720.29938-1-tpluszz77@gmail.com/ (v1) Qi Tang (2): bpf: reject direct access to nullable PTR_TO_BUF pointers selftests/bpf: add test for nullable PTR_TO_BUF access kernel/bpf/verifier.c | 3 ++- tools/testing/selftests/bpf/progs/iter_buf_null_fail.c | 51 +++++++++++++++++ 2 files changed, 53 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/iter_buf_null_fail.c