From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f173.google.com (mail-pl1-f173.google.com [209.85.214.173]) (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 2DB882F7EE5 for ; Fri, 5 Jun 2026 20:20:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780690860; cv=none; b=rIZK0qlVTCecuUT3ffCw4SYhRoO3gLh/PPEiHr8q4jhNPcMvhg+g64O5rFgHgYnUxwjpBiyK35aeKk+eGrtOu7TuUDwOM865XfeISxGyiV62WEMuSeny2F8856LxC6p0SLl7SlrD2cR5j5M7lMLmSYRdtvhlNZuoPxwRMfoj81o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780690860; c=relaxed/simple; bh=VKa1p6dcOvuI2DFfe1gs5QWC1H4dbHxEPdSpJFQaEaI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=haU6yIiut/7vThwA6R50i2+HsaHSX82MSNvijvsEgwobGDE8VFh6p5ieox/eV268NonEXZd4zA0SPnWerXEwHFpib9ZW2OknJk9SBGDFz5FaAFlI6JBLVolVmQ8JUH3ar6u9hJ3ktLcOOapzx3FBVkYHxFGZUSiOOT8wBxdKkO4= 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=kNJ7Krlu; arc=none smtp.client-ip=209.85.214.173 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="kNJ7Krlu" Received: by mail-pl1-f173.google.com with SMTP id d9443c01a7336-2bf1f074a12so24392155ad.0 for ; Fri, 05 Jun 2026 13:20:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1780690858; x=1781295658; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=H9A8Nis1U71TWs13OCltH/HpVgGML0i1G++ntwFggfE=; b=kNJ7KrluUXmFE6QSJgP0lDFWlb8jcgoNsF3CNiqf5QODBehh2vlz6CLQUqwsvjole2 /U+XID+UaZEF6b+kTvc/mgRvBNryyAjbr58V5e1Y+UzjOalHCghjDuHv+7fgyqmgqCb6 J2Ef8tPHeEJlkcTMGRCINY2S4xBHropcl+rS9VfB4iJyBiHn8E2+U62wjIR8SBzKJqTh 5TSi6QgSVQmOorMoHmFxOAlJmlU+nL57e5SpwcSNzVqE9oBalGmo/mJQLfPmryoQSXYE LSMp53Nb45Bxe/4uzXoBGOvXuoXASbAHIctmt55kgDPrjZ0RxLbtOBMm2N34k9+Pn82J MFrA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780690858; x=1781295658; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=H9A8Nis1U71TWs13OCltH/HpVgGML0i1G++ntwFggfE=; b=QmvksO+2kjLOfu203xOHXUZ6ky1DlkQRz+trZMFR+aS5bJEQbEx8eqqKzQNzsXf2fy RgcGggUi186KwnN/1kKYl6CIZ2IeREJfFaFyh9MNgxZZXYhzRY4qBFj7Qea76ar4hAnX TPs31HuGz7ylk+fPUUE0qv018xh66skwsQ9Mc55fR9AHJe4Xm8D21C/60s67NHErPf7X HEI6iNT+CzNUBR+KysBMhAA3PFREuiXGrH9T2ljEZLp1zEjdVUqvv3fGKMzmREV2Iy3h b6c8DkNIZsE3ZtqltETKwgXgJTDMIzrP8JXMKM7zXmFUlSUrk4B+2WZfIXMetLp3YuIl ssqw== X-Gm-Message-State: AOJu0YxGN+2WDCYO3B25EQFzHt3KrsBo7Ztrh+cbzm2ZPYUB0lzczHyC Jd3LbBRl3Hn83sDXbhIOPIynG1K65KKiLtIRI+8h+e0LF7XSo2vR01BF X-Gm-Gg: Acq92OEQkjaGKLG9gFojosPWx59rAqipkD7vsydI+jESR2j7Vdu2Lm2d5mL3MjV7XYk /y974R9XfF0rmrAuEeTrJ/0TJFIoHPhiunzr40hf7uoldzhxo9+U5jM/77cj/gLLjs48v2lFKgg MAEPXCg801SK5SIjli+LZdk2kv8TYlMvdI2rcONjOgWQV9ecR07HGM52rHZHwTn8eovJTAD4xc4 kyc6zE8T219gqr42ICdtIoi+ADb5KaJDqQ8Uu7I5wR8cXIoRnOoOyofkEO5hyJL5vc9t9AJ6yZA 9N8OaOdv9pfqilj/bdDNFDHTgEs4Zf8z7A8v7qa3XtHtmrQdlraXhwoAfFPegEpsxUthe/w2VoA 26ZT2A3dF8FYCf+wiWtttks9mm0wLrqpcKolWAK/JtL8OfYxPdiu+RMUIcLahyBEC7xNkEZeSw6 cnl80XK2D+IZbgvjAjVBp8Yr8= X-Received: by 2002:a17:902:f60d:b0:2ba:4e84:966 with SMTP id d9443c01a7336-2c1e85e0896mr52701875ad.36.1780690858479; Fri, 05 Jun 2026 13:20:58 -0700 (PDT) Received: from localhost ([2a03:2880:ff:2::]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2c16609e234sm103007865ad.53.2026.06.05.13.20.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 05 Jun 2026 13:20:58 -0700 (PDT) From: Amery Hung To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, alexei.starovoitov@gmail.com, andrii@kernel.org, daniel@iogearbox.net, eddyz87@gmail.com, memxor@gmail.com, martin.lau@kernel.org, mykyta.yatsenko5@gmail.com, ameryhung@gmail.com, kernel-team@meta.com Subject: [PATCH bpf-next v3 1/5] bpf: Fix dead error check on acquire_reference() in check_kfunc_call Date: Fri, 5 Jun 2026 13:20:52 -0700 Message-ID: <20260605202056.1780352-2-ameryhung@gmail.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260605202056.1780352-1-ameryhung@gmail.com> References: <20260605202056.1780352-1-ameryhung@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit acquire_reference() returns a signed int that may be a negative errno but was converted to unsigned, which makes the subsequent error check deadcode. Fix it by declaring 'id' as int so the error path is taken correctly. Fixes: 308c7a0ae885 ("bpf: Refactor object relationship tracking and fix dynptr UAF bug") Acked-by: Eduard Zingerman Signed-off-by: Amery Hung --- kernel/bpf/verifier.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8ed484cb1a8a..6446db9628ae 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -12817,9 +12817,10 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, struct bpf_kfunc_call_arg_meta meta; struct bpf_insn_aux_data *insn_aux; int err, insn_idx = *insn_idx_p; - u32 i, nargs, ptr_type_id, id; const struct btf_param *args; + u32 i, nargs, ptr_type_id; struct btf *desc_btf; + int id; /* skip for now, but return error when we find this in fixup_kfunc_call */ if (!insn->imm) -- 2.53.0-Meta