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spf=fail smtp.mailfrom=kraxel@redhat.com From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Tue, 17 Oct 2017 10:24:59 +0200 Message-Id: <20171017082502.7885-2-kraxel@redhat.com> In-Reply-To: <20171017082502.7885-1-kraxel@redhat.com> References: <20171017082502.7885-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Tue, 17 Oct 2017 08:25:08 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 1/4] vga: drop line_offset variable X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_6 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Signed-off-by: Gerd Hoffmann --- hw/display/vga.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/hw/display/vga.c b/hw/display/vga.c index ed24ef7076..bf774e3402 100644 --- a/hw/display/vga.c +++ b/hw/display/vga.c @@ -1464,7 +1464,7 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) { DisplaySurface *surface =3D qemu_console_surface(s->con); int y1, y, update, linesize, y_start, double_scan, mask, depth; - int width, height, shift_control, line_offset, bwidth, bits; + int width, height, shift_control, bwidth, bits; ram_addr_t page0, page1; DirtyBitmapSnapshot *snap =3D NULL; int disp_width, multi_scan, multi_run; @@ -1614,7 +1614,6 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) s->cursor_invalidate(s); } =20 - line_offset =3D s->line_offset; #if 0 printf("w=3D%d h=3D%d v=3D%d line_offset=3D%d cr[0x09]=3D0x%02x cr[0x1= 7]=3D0x%02x linecmp=3D%d sr[0x01]=3D0x%02x\n", width, height, v, line_offset, s->cr[9], s->cr[VGA_CRTC_MODE], @@ -1629,7 +1628,7 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) =20 if (!full_update) { ram_addr_t region_start =3D addr1; - ram_addr_t region_end =3D addr1 + line_offset * height; + ram_addr_t region_end =3D addr1 + s->line_offset * height; vga_sync_dirty_bitmap(s); if (s->line_compare < height) { /* split screen mode */ @@ -1681,7 +1680,7 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) if (!multi_run) { mask =3D (s->cr[VGA_CRTC_MODE] & 3) ^ 3; if ((y1 & mask) =3D=3D mask) - addr1 +=3D line_offset; + addr1 +=3D s->line_offset; y1++; multi_run =3D multi_scan; } else { --=20 2.9.3 From nobody Sun May 5 05:38:40 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (208.118.235.17 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1508228910816931.1152653768398; Tue, 17 Oct 2017 01:28:30 -0700 (PDT) Received: from localhost ([::1]:37175 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e4NEf-0004e1-4D for importer@patchew.org; Tue, 17 Oct 2017 04:28:25 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59446) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e4NBY-0002cu-QL for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e4NBW-00061d-Fo for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37990) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e4NBW-00060X-7A for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:10 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 47A9D81127 for ; Tue, 17 Oct 2017 08:25:09 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-239.ams2.redhat.com [10.36.116.239]) by smtp.corp.redhat.com (Postfix) with ESMTP id C48B864437; Tue, 17 Oct 2017 08:25:04 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id C1FE54FD6B; Tue, 17 Oct 2017 10:25:02 +0200 (CEST) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 47A9D81127 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=kraxel@redhat.com From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Tue, 17 Oct 2017 10:25:00 +0200 Message-Id: <20171017082502.7885-3-kraxel@redhat.com> In-Reply-To: <20171017082502.7885-1-kraxel@redhat.com> References: <20171017082502.7885-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Tue, 17 Oct 2017 08:25:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 2/4] vga: handle cirrus vbe mode wraparounds. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann , P J P Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Commit "3d90c62548 vga: stop passing pointers to vga_draw_line* functions" is incomplete. It doesn't handle the case that the vga rendering code tries to create a shared surface, i.e. a pixman image backed by vga video memory. That can not work in case the guest display wraps from end of video memory to the start. So force shadowing in that case. Also adjust the snapshot region calculation. Can trigger with cirrus only, when programming vbe modes using the bochs api (stdvga, also qxl and virtio-vga in vga compat mode) wrap arounds can't happen. Fixes: CVE-2017-13672 Fixes: 3d90c6254863693a6b13d918d2b8682e08bbc681 Cc: P J P Reported-by: David Buchanan Signed-off-by: Gerd Hoffmann Message-id: 20171010141323.14049-3-kraxel@redhat.com --- hw/display/vga.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) diff --git a/hw/display/vga.c b/hw/display/vga.c index bf774e3402..1afceb6f16 100644 --- a/hw/display/vga.c +++ b/hw/display/vga.c @@ -1465,13 +1465,13 @@ static void vga_draw_graphic(VGACommonState *s, int= full_update) DisplaySurface *surface =3D qemu_console_surface(s->con); int y1, y, update, linesize, y_start, double_scan, mask, depth; int width, height, shift_control, bwidth, bits; - ram_addr_t page0, page1; + ram_addr_t page0, page1, region_start, region_end; DirtyBitmapSnapshot *snap =3D NULL; int disp_width, multi_scan, multi_run; uint8_t *d; uint32_t v, addr1, addr; vga_draw_line_func *vga_draw_line =3D NULL; - bool share_surface; + bool share_surface, force_shadow =3D false; pixman_format_code_t format; #ifdef HOST_WORDS_BIGENDIAN bool byteswap =3D !s->big_endian_fb; @@ -1484,6 +1484,15 @@ static void vga_draw_graphic(VGACommonState *s, int = full_update) s->get_resolution(s, &width, &height); disp_width =3D width; =20 + region_start =3D (s->start_addr * 4); + region_end =3D region_start + s->line_offset * height; + if (region_end > s->vbe_size) { + /* wraps around (can happen with cirrus vbe modes) */ + region_start =3D 0; + region_end =3D s->vbe_size; + force_shadow =3D true; + } + shift_control =3D (s->gr[VGA_GFX_MODE] >> 5) & 3; double_scan =3D (s->cr[VGA_CRTC_MAX_SCAN] >> 7); if (shift_control !=3D 1) { @@ -1523,7 +1532,7 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) format =3D qemu_default_pixman_format(depth, !byteswap); if (format) { share_surface =3D dpy_gfx_check_format(s->con, format) - && !s->force_shadow; + && !s->force_shadow && !force_shadow; } else { share_surface =3D false; } @@ -1627,8 +1636,6 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) y1 =3D 0; =20 if (!full_update) { - ram_addr_t region_start =3D addr1; - ram_addr_t region_end =3D addr1 + s->line_offset * height; vga_sync_dirty_bitmap(s); if (s->line_compare < height) { /* split screen mode */ @@ -1651,10 +1658,17 @@ static void vga_draw_graphic(VGACommonState *s, int= full_update) addr =3D (addr & ~0x8000) | ((y1 & 2) << 14); } update =3D full_update; - page0 =3D addr; - page1 =3D addr + bwidth - 1; + page0 =3D addr & s->vbe_size_mask; + page1 =3D (addr + bwidth - 1) & s->vbe_size_mask; if (full_update) { update =3D 1; + } else if (page1 < page0) { + /* scanline wraps from end of video memory to the start */ + assert(force_shadow); + update =3D memory_region_snapshot_get_dirty(&s->vram, snap, + page0, 0); + update |=3D memory_region_snapshot_get_dirty(&s->vram, snap, + page1, 0); } else { update =3D memory_region_snapshot_get_dirty(&s->vram, snap, page0, page1 - page0= ); --=20 2.9.3 From nobody Sun May 5 05:38:40 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; 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Tue, 17 Oct 2017 04:25:09 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B91501F57C for ; Tue, 17 Oct 2017 08:25:08 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-239.ams2.redhat.com [10.36.116.239]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1E846443D; Tue, 17 Oct 2017 08:25:04 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id C9C913F10B; Tue, 17 Oct 2017 10:25:02 +0200 (CEST) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com B91501F57C Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=kraxel@redhat.com From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Tue, 17 Oct 2017 10:25:01 +0200 Message-Id: <20171017082502.7885-4-kraxel@redhat.com> In-Reply-To: <20171017082502.7885-1-kraxel@redhat.com> References: <20171017082502.7885-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 17 Oct 2017 08:25:08 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 3/4] vga: add ram_addr_t cast X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Reported by Coverity. Fixes: CID 1381409 Signed-off-by: Gerd Hoffmann Message-id: 20171010141323.14049-4-kraxel@redhat.com --- hw/display/vga.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/display/vga.c b/hw/display/vga.c index 1afceb6f16..1d19f6bc48 100644 --- a/hw/display/vga.c +++ b/hw/display/vga.c @@ -1485,7 +1485,7 @@ static void vga_draw_graphic(VGACommonState *s, int f= ull_update) disp_width =3D width; =20 region_start =3D (s->start_addr * 4); - region_end =3D region_start + s->line_offset * height; + region_end =3D region_start + (ram_addr_t)s->line_offset * height; if (region_end > s->vbe_size) { /* wraps around (can happen with cirrus vbe modes) */ region_start =3D 0; --=20 2.9.3 From nobody Sun May 5 05:38:40 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (208.118.235.17 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1508228811267733.2177776278379; Tue, 17 Oct 2017 01:26:51 -0700 (PDT) Received: from localhost ([::1]:37170 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e4NCw-0003Nx-9j for importer@patchew.org; Tue, 17 Oct 2017 04:26:38 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59478) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e4NBa-0002dW-0W for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e4NBV-00060P-GG for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36100) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e4NBV-0005yO-9r for qemu-devel@nongnu.org; Tue, 17 Oct 2017 04:25:09 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 88F79C0587C6; Tue, 17 Oct 2017 08:25:07 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-239.ams2.redhat.com [10.36.116.239]) by smtp.corp.redhat.com (Postfix) with ESMTP id B9B095C3FF; Tue, 17 Oct 2017 08:25:04 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id D1AA240559; Tue, 17 Oct 2017 10:25:02 +0200 (CEST) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 88F79C0587C6 Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=kraxel@redhat.com From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Tue, 17 Oct 2017 10:25:02 +0200 Message-Id: <20171017082502.7885-5-kraxel@redhat.com> In-Reply-To: <20171017082502.7885-1-kraxel@redhat.com> References: <20171017082502.7885-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 17 Oct 2017 08:25:07 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 4/4] cirrus: fix oob access in mode4and5 write functions X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gerd Hoffmann , Prasad J Pandit Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Move dst calculation into the loop, so we apply the mask on each interation and will not overflow vga memory. Cc: Prasad J Pandit Reported-by: Niu Guoxiang Signed-off-by: Gerd Hoffmann Message-id: 20171011084314.21752-1-kraxel@redhat.com --- hw/display/cirrus_vga.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c index b4d579857a..bc32bf1e39 100644 --- a/hw/display/cirrus_vga.c +++ b/hw/display/cirrus_vga.c @@ -2038,15 +2038,14 @@ static void cirrus_mem_writeb_mode4and5_8bpp(Cirrus= VGAState * s, unsigned val =3D mem_value; uint8_t *dst; =20 - dst =3D s->vga.vram_ptr + (offset &=3D s->cirrus_addr_mask); for (x =3D 0; x < 8; x++) { + dst =3D s->vga.vram_ptr + ((offset + x) & s->cirrus_addr_mask); if (val & 0x80) { *dst =3D s->cirrus_shadow_gr1; } else if (mode =3D=3D 5) { *dst =3D s->cirrus_shadow_gr0; } val <<=3D 1; - dst++; } memory_region_set_dirty(&s->vga.vram, offset, 8); } @@ -2060,8 +2059,8 @@ static void cirrus_mem_writeb_mode4and5_16bpp(CirrusV= GAState * s, unsigned val =3D mem_value; uint8_t *dst; =20 - dst =3D s->vga.vram_ptr + (offset &=3D s->cirrus_addr_mask); for (x =3D 0; x < 8; x++) { + dst =3D s->vga.vram_ptr + ((offset + 2 * x) & s->cirrus_addr_mask = & ~1); if (val & 0x80) { *dst =3D s->cirrus_shadow_gr1; *(dst + 1) =3D s->vga.gr[0x11]; @@ -2070,7 +2069,6 @@ static void cirrus_mem_writeb_mode4and5_16bpp(CirrusV= GAState * s, *(dst + 1) =3D s->vga.gr[0x10]; } val <<=3D 1; - dst +=3D 2; } memory_region_set_dirty(&s->vga.vram, offset, 16); } --=20 2.9.3