From nobody Fri Oct 6 14:25:02 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4S29gL684nz4wgbH; Fri, 6 Oct 2023 14:25:02 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4S29gL5gXHz3QWp; Fri, 6 Oct 2023 14:25:02 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1696602302; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ydchxDGLVTdouxGgENzP8fR50JLDXGaCtyRvjl/quz8=; b=nZmG9RfUbMZzokhtiyk2YlMQs60qW2oODoRTO+dCldr4LGLB5mkTMzxzoUAqPr8TyCeupK Bpuotbc0S8olIM9/T73HTjofaMKizWKR4SDkEAg3dHcQpz8SxjE6z8r8iPs0zKnpIJItnr E97E39yj/84BM45jSpA6O055xugaNVrivg0RX1+3olsq8vHA4bYgfRpbh7WNX9AcFe8wuc rObaflh6xA6yxZYABFczumFkq+KQXk4j8me0NzG2OzAYe+E+GjkCLeox5bS8z5y2entPuh YSRzpW2QrdN1akf/iz9ZEfWKhAzOwOrMb42j/w36VCGVJ9AILtwB6fquIrX77g== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1696602302; a=rsa-sha256; cv=none; b=HxZ8sV/Sq6s4Z0JM4q1L4M7RzPSNBVw8TMt63FftkldAretu+ic8WxvIOsx11v6YPYxP0A 8QSCHtVKW9FLei89ByS7vkOYkC02IOWlrtrIWqDlaYD7xfgSsrWpppeCwGoqz9jV3jwPQJ ePZ5FI4oLcU/43ClWOvDJku6nLRCWXB4ZZVuhCrBcsVNjsMWP7bM31tkF+g0unysd5U82y 1OmTx5j0r9FEyp8AR/ai0UV9/v6i1ypugDCTcQJbQ0XcDMhYmjRoq23D85uglePkzSBN3/ iokrT/ZtaWcCayFu+S+UmXJJXVU4MkVz61tzBCSUcrB/CTee6Gqz++mw6kptYw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1696602302; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ydchxDGLVTdouxGgENzP8fR50JLDXGaCtyRvjl/quz8=; b=ycWgU89+dF9RNIEbO6gem1BcDqRISiSiqETUTz4X40ak/9s4YLXX+jQgLqJ29w3mj+FfVM 2hYdEvOTeqj29Bu+ctKXwGww9bRErPmu8o3iQCYscMXbJc9+hc8VXPgxByKtn6/2gn6rFi lwBQZLpw3LPPgLXNRWqpyuYCb+1XE62U1dUJ9ujf3zAklVaH+gj7EbjjA6zdPGph+GjCvd jpbG+Z58qQiZAxDBzM/dCqpNVyN/HxRDGOpW7lVwoeKDK2y9i+YMVxmKYNUFxD94Piqafp 3hCBTmxynXw0K5IsFam4a71yVMJEWYJlA1d0F6kG7xzxW93dHqQLHTCTT+H+sw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4S29gL4StkzrXF; Fri, 6 Oct 2023 14:25:02 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 396EP2B0092901; Fri, 6 Oct 2023 14:25:02 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 396EP2N9092896; Fri, 6 Oct 2023 14:25:02 GMT (envelope-from git) Date: Fri, 6 Oct 2023 14:25:02 GMT Message-Id: <202310061425.396EP2N9092896@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: "Bjoern A. Zeeb" Subject: git: 2709483a725e - stable/14 - linuxkpi: fix iteration in __sg_alloc_table_from_pages List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: bz X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: 2709483a725e1da2d443d9e391bfaa0f223099be Auto-Submitted: auto-generated The branch stable/14 has been updated by bz: URL: https://cgit.FreeBSD.org/src/commit/?id=2709483a725e1da2d443d9e391bfaa0f223099be commit 2709483a725e1da2d443d9e391bfaa0f223099be Author: Austin Shafer AuthorDate: 2023-09-06 14:08:05 +0000 Commit: Bjoern A. Zeeb CommitDate: 2023-10-06 12:47:39 +0000 linuxkpi: fix iteration in __sg_alloc_table_from_pages Commit 3f686532c9b4 tried to fix an issue with not properly starting at the first page in the sg list to prevent a panic. This worked but with the side effect of incrementing "s" during the final iteration causing it to be NULL since the list had ended. In cases non-DEBUG kernels this causes a panic with drm-5.15, since "s" is NULL when we later pass it to sg_mark_end(). This change decouples the iteration sg from the return value so that it is never incremented past the final page in the chain. Reviewed by: manu Differential Revision: https://reviews.freebsd.org/D41574 (cherry picked from commit 09b0401e91a92bcb58ea1873857b42f8211f660f) --- sys/compat/linuxkpi/common/include/linux/scatterlist.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/sys/compat/linuxkpi/common/include/linux/scatterlist.h b/sys/compat/linuxkpi/common/include/linux/scatterlist.h index 0e4cc90e57a5..e462d5c649f1 100644 --- a/sys/compat/linuxkpi/common/include/linux/scatterlist.h +++ b/sys/compat/linuxkpi/common/include/linux/scatterlist.h @@ -343,7 +343,7 @@ __sg_alloc_table_from_pages(struct sg_table *sgt, { unsigned int i, segs, cur, len; int rc; - struct scatterlist *s; + struct scatterlist *s, *sg_iter; #if defined(LINUXKPI_VERSION) && LINUXKPI_VERSION >= 51300 if (prv != NULL) { @@ -377,10 +377,18 @@ __sg_alloc_table_from_pages(struct sg_table *sgt, #endif cur = 0; - for (i = 0, s = sgt->sgl; i < sgt->orig_nents; i++) { + for_each_sg(sgt->sgl, sg_iter, sgt->orig_nents, i) { unsigned long seg_size; unsigned int j; + /* + * We need to make sure that when we exit this loop "s" has the + * last sg in the chain so we can call sg_mark_end() on it. + * Only set this inside the loop since sg_iter will be iterated + * until it is NULL. + */ + s = sg_iter; + len = 0; for (j = cur + 1; j < count; ++j) { len += PAGE_SIZE; @@ -394,8 +402,6 @@ __sg_alloc_table_from_pages(struct sg_table *sgt, size -= seg_size; off = 0; cur = j; - - s = sg_next(s); } KASSERT(s != NULL, ("s is NULL after loop in __sg_alloc_table_from_pages()"));