From nobody Sat Jul 4 21:05:53 2026 Received: from mail-wm1-f49.google.com (mail-wm1-f49.google.com [209.85.128.49]) (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 7254342E00D for ; Mon, 29 Jun 2026 16:05:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.49 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782749158; cv=none; b=Z0Gu2cwOebqUTeykIEfgb4VoWZcKHagn5i3MxQEIXtVWEFDF97YrtbrZArMiajMsZ9UFDaeEOq8amB/uTlxDzKHsjFWGca/gE97o/5TwzaZbZPPOtBvJWJYhFkPUUbiUFhmTzwz0/WQKcUCz/A43YfIuUOxvE6FSU0+e5FS+ztA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782749158; c=relaxed/simple; bh=rfBVDm6I82Gsm4RblykLarjb7LJKojnvyukMTrTtBTI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=aIzSLr5KOHBHIU0Gwz/bZiBDh5a+3Xdn+erMapVXiluEFlqPWGkhIFlfl/CWzFNjgCJByCC9EYJ/24ub8cmk/54+6PwextLMp8BwiM3xeDmnGoizxISMWnUZdh3uSm/uydu1Do5oS1hkOEj3bD9U3PsWZlg++v2PN0XJubLodyc= 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=EYdz4pYO; arc=none smtp.client-ip=209.85.128.49 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="EYdz4pYO" Received: by mail-wm1-f49.google.com with SMTP id 5b1f17b1804b1-493a287b8c1so11830595e9.0 for ; Mon, 29 Jun 2026 09:05:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782749156; x=1783353956; 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=urju7AHNAPTsZhmiiZ2fXVN5kyTyXWHOnIy66aKFET0=; b=EYdz4pYOnM8KPg+YDvL4zvu3tjWO2Vnt7XSW5tVC0E8xuPta+zEu2xSRUFhnHq6xNG joiRQlSduZK03ndl0Y4h1R/RnuyBxl9J8Igj6OH0qp4AuYHjiwpxDvcp3AJoLewWFFFN ss4o1BKBQI5xvA4cZ76i2HZXYXlIVmH5cW5r7Um+JkY0aluNjeHAKQ8YRCHNiOBcu+6n 76ByZQBZ2Qb3mMKMjKxUQFpX/Ad/lsFxZ1vcWRS9kjlvEf8WN14oMi/M2akrq2942Z9J U37U0iwd64HXR52BtX+DbOI3dGyAMo/lclwgkRvg6K2i9EY0Gocq5HU3OoZxBsW9G0Qz 4k1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782749156; x=1783353956; 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=urju7AHNAPTsZhmiiZ2fXVN5kyTyXWHOnIy66aKFET0=; b=ZTyXV9e6HEsN+l5AT9utjJNcCBBfcpURuCsauEFaeBTrcZzIFqHcYb5bZdu5MVYOiR dBz1rtxsToDhH5hcNMxDAk917G91DXEY5HeNwduPfFDgoaLYgOIIeUgaYzgKjfwlCHCl NoADpS5QvTEQ5/MwKCEArJkF9GNeEJJ9CzDMC11I+rK3iZzGKst3ocD3DyrHIBL3gC6y eUwiVX01rO2nZf3RowMLY3an8cqegrYzN9rjbtE5auIHRWgkCnMS12B87w3yffM+HvnG 2FOd1DNjV+FURUj5WQ24fgiYxwomrc5Hb69i2q9aVaxP9W8FDPOeBaWy7B1CPraRRri/ sx+A== X-Forwarded-Encrypted: i=1; AFNElJ/4xsazqVND8HLWSJGnZ33iOdcZWMn+keeVU/PxAoKfXt/QOvrLvHOd106Sb1le9pPngsKpVQc5Ec8bAyE=@vger.kernel.org X-Gm-Message-State: AOJu0YwGl41A8WIpKNZnL66Q7NPwj0PaRSzYswXsqgd4ZOtkdVtKK4DU u3XihdISJqhGEXKsboeR6UJ7Bed1Pyp0ydEu4z8kFBtkBdud20Kd5TnS X-Gm-Gg: AfdE7cnLuG9XyeUpbDMylJsgW7iwUj1jEuDE4SaqGCsFe8twqXTLpTkpV4HO2/lToau wFScUL8g9aZ9BFZagR5BjVA6s02C2j2YN9N3KzkyGPCvkGXqI4zWBTaLJn3RV1AWKuLlNN4ma9Y FjBjmuiFRziEsBfPL769LkyMF+Pjw0CWo4WWak3ogYZ8N9U569CFZw4plEC2fQQqMGor4R48TQv 7/0JFQ5Ru8zquRN/LOR6YBcbuBsBtkDSwq7nXWRai9nIRTJ+LQkicsO262+aSFrGBEvomsvXsXu NvKIGtn/PAACQD4x+4uC8ghMtbMEFNGZeDbE9boKGSbaNYhfQ1b0fwxhFWr7jq9ecb4dRlVJO/s UGJ+x1d5iG53ljFGYdoIPFDKa4z1LyH0X76It4oe0hxrLDuB7MbHjnsQNoI1GJiw309y0kXVwcu MiuHtIr84NfPcM6byGAE1mT2EsMA== X-Received: by 2002:a05:600c:8b4b:b0:493:b55f:bca2 with SMTP id 5b1f17b1804b1-493b82c3225mr4557905e9.34.1782749155666; Mon, 29 Jun 2026 09:05:55 -0700 (PDT) Received: from Dev-Null-MSI ([2a0d:3344:52ac:a808:98a4:4381:be45:536f]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-472bca3caccsm16289696f8f.33.2026.06.29.09.05.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Jun 2026 09:05:55 -0700 (PDT) From: Yousef Alhouseen To: Juergen Gross Cc: Stefano Stabellini , Oleksandr Tyshchenko , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, Yousef Alhouseen Subject: [PATCH] xen/front-pgdir-shbuf: free grant reference head on errors Date: Mon, 29 Jun 2026 18:05:17 +0200 Message-ID: <20260629160517.29340-1-alhouseenyousef@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" grant_references() allocates a private grant-reference head before claiming references for the page directory and, for guest-owned buffers, the data pages. The success path frees the remaining head, but claim failures and grant_refs_for_buffer() errors return immediately. Unwind through a common exit path so the private grant-reference head is released even when granting fails part-way through setup. The caller still tears down any references already stored in buf->grefs. Signed-off-by: Yousef Alhouseen Reviewed-by: Stefano Stabellini --- drivers/xen/xen-front-pgdir-shbuf.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/xen/xen-front-pgdir-shbuf.c b/drivers/xen/xen-front-pg= dir-shbuf.c index 9c7d8af6e6a1..428187edf85d 100644 --- a/drivers/xen/xen-front-pgdir-shbuf.c +++ b/drivers/xen/xen-front-pgdir-shbuf.c @@ -445,8 +445,10 @@ static int grant_references(struct xen_front_pgdir_shb= uf *buf) unsigned long frame; =20 cur_ref =3D gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) - return cur_ref; + if (cur_ref < 0) { + ret =3D cur_ref; + goto out_free_refs; + } =20 frame =3D xen_page_to_gfn(virt_to_page(buf->directory + PAGE_SIZE * i)); @@ -457,11 +459,13 @@ static int grant_references(struct xen_front_pgdir_sh= buf *buf) if (buf->ops->grant_refs_for_buffer) { ret =3D buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j); if (ret) - return ret; + goto out_free_refs; } =20 + ret =3D 0; +out_free_refs: gnttab_free_grant_references(priv_gref_head); - return 0; + return ret; } =20 /* --=20 2.54.0