kernel/linux.git/drivers/gpu/drm/drm_edid.c, branch v6.6.150

drm/edid: fix OOB read in drm_parse_tiled_block()

2026-07-24T14:03:21+00:00

[ Upstream commit faaa1e1155833e7d4ce7e3cfaf64c0d636b190db ] drm_parse_tiled_block() casts the DisplayID block to a struct displayid_tiled_block and reads the full fixed layout up to tile->topology_id[7] without checking block->num_bytes. The DisplayID iterator only validates the declared payload length, so a crafted EDID can advertise a tiled-display block (tag DATA_BLOCK_TILED_DISPLAY, or DATA_BLOCK_2_TILED_DISPLAY_TOPOLOGY for v2.0) with a small num_bytes at the end of a DisplayID extension. The read then runs past the end of the exact-sized kmemdup()'d EDID allocation, a heap out-of-bounds read. Reject blocks shorter than the spec's 22-byte tiled payload before reading the fixed struct, as drm_parse_vesa_mso_data() already does. BUG: KASAN: slab-out-of-bounds in drm_edid_connector_update Read of size 2 at addr ffff888010077700 by task exploit/147 dump_stack_lvl (lib/dump_stack.c:94 ...) print_report (mm/kasan/report.c:378 ...) kasan_report (mm/kasan/report.c:595) drm_edid_connector_update (drivers/gpu/drm/drm_edid.c:7581) bochs_connector_helper_get_modes (drivers/gpu/drm/tiny/bochs.c:574) drm_helper_probe_single_connector_modes (drivers/gpu/drm/drm_probe_helper.c:426) status_store (drivers/gpu/drm/drm_sysfs.c:219) ... vfs_write (fs/read_write.c:595 fs/read_write.c:688) ksys_write (fs/read_write.c:740) Fixes: 40d9b043a89e ("drm/connector: store tile information from displayid (v3)") Reported-by: Weiming Shi Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Xiang Mei Reviewed-by: Jani Nikula Link: https://patch.msgid.link/20260615184737.899892-1-xmei5@asu.edu Signed-off-by: Jani Nikula Signed-off-by: Sasha Levin

drm/edid: fixed the bug that hdr metadata was not reset

2025-06-04T12:42:20+00:00

commit 6692dbc15e5ed40a3aa037aced65d7b8826c58cd upstream. When DP connected to a device with HDR capability, the hdr structure was filled.Then connected to another sink device without hdr capability, but the hdr info still exist. Fixes: e85959d6cbe0 ("drm: Parse HDR metadata info from EDID") Cc: # v5.3+ Signed-off-by: "feijuan.li" Reviewed-by: Jani Nikula Link: https://lore.kernel.org/r/20250514063511.4151780-1-feijuan.li@samsung.com Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman

drm/connector: add mutex to protect ELD from concurrent access

2025-02-17T08:40:04+00:00

[ Upstream commit df7c8e3dde37a9d81c0613285b43600f3cc70f34 ] The connector->eld is accessed by the .get_eld() callback. This access can collide with the drm_edid_to_eld() updating the data at the same time. Add drm_connector.eld_mutex to protect the data from concurrenct access. Individual drivers are not updated (to reduce possible issues while applying the patch), maintainers are to find a best suitable way to lock that mutex while accessing the ELD data. Reviewed-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20241206-drm-connector-eld-mutex-v2-1-c9bce1ee8bea@linaro.org Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin

drm/edid: Parse topology block for all DispID structure v1.x

2024-06-12T09:12:05+00:00

[ Upstream commit e0a200ab4b72afd581bd6f82fc1ef510a4fb5478 ] DisplayID spec v1.3 revision history notes do claim that the toplogy block was added in v1.3 so requiring structure v1.2 would seem correct, but there is at least one EDID in edid.tv with a topology block and structure v1.0. And there are also EDIDs with DisplayID structure v1.3 which seems to be totally incorrect as DisplayID spec v1.3 lists structure v1.2 as the only legal value. Unfortunately I couldn't find copies of DisplayID spec v1.0-v1.2 anywhere (even on vesa.org), so I'll have to go on empirical evidence alone. We used to parse the topology block on all v1.x structures until the check for structure v2.0 was added. Let's go back to doing that as the evidence does suggest that there are DisplayIDs in the wild that would miss out on the topology stuff otherwise. Also toss out DISPLAY_ID_STRUCTURE_VER_12 entirely as it doesn't appear we can really use it for anything. I *think* we could technically skip all the structure version checks as the block tags shouldn't conflict between v2.0 and v1.x. But no harm in having a bit of extra sanity checks I guess. So far I'm not aware of any user reported regressions from overly strict check, but I do know that it broke igt/kms_tiled_display's fake DisplayID as that one gets generated with structure v1.0. Cc: Jani Nikula Cc: Dmitry Osipenko Fixes: c5a486af9df7 ("drm/edid: parse Tiled Display Topology Data Block for DisplayID 2.0") Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20240410180139.21352-1-ville.syrjala@linux.intel.com Acked-by: Jani Nikula Signed-off-by: Sasha Levin

drm/edid: also call add modes in EDID connector update fallback

2023-12-20T16:02:04+00:00

commit 759f14e20891de72e676d9d738eb2c573aa15f52 upstream. When the separate add modes call was added back in commit c533b5167c7e ("drm/edid: add separate drm_edid_connector_add_modes()"), it failed to address drm_edid_override_connector_update(). Also call add modes there. Reported-by: bbaa Closes: https://lore.kernel.org/r/930E9B4C7D91FDFF+29b34d89-8658-4910-966a-c772f320ea03@bbaa.fun Fixes: c533b5167c7e ("drm/edid: add separate drm_edid_connector_add_modes()") Cc: # v6.3+ Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20231207093821.2654267-1-jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman

drm/edid: Fixup h/vsync_end instead of h/vtotal

2023-11-28T17:19:39+00:00

[ Upstream commit 2682768bde745b10ae126a322cdcaf532cf88851 ] There are some weird EDIDs floating around that have the sync pulse extending beyond the end of the blanking period. On the currently problemtic machine (HP Omni 120) EDID reports the following mode: "1600x900": 60 108000 1600 1780 1860 1800 900 910 913 1000 0x40 0x5 which is then "corrected" to have htotal=1861 by the current drm_edid.c code. The fixup code was originally added in commit 7064fef56369 ("drm: work around EDIDs with bad htotal/vtotal values"). Googling around we end up in https://bugs.launchpad.net/ubuntu/hardy/+source/xserver-xorg-video-intel/+bug/297245 where we find an EDID for a Dell Studio 15, which reports: (II) VESA(0): clock: 65.0 MHz Image Size: 331 x 207 mm (II) VESA(0): h_active: 1280 h_sync: 1328 h_sync_end 1360 h_blank_end 1337 h_border: 0 (II) VESA(0): v_active: 800 v_sync: 803 v_sync_end 809 v_blanking: 810 v_border: 0 Note that if we use the hblank size (as opposed of the hsync_end) from the DTD to determine htotal we get exactly 60Hz refresh rate in both cases, whereas using hsync_end to determine htotal we get a slightly lower refresh rates. This makes me believe the using the hblank size is what was intended even in those cases. Also note that in case of the HP Onmi 120 the VBIOS boots with these: crtc timings: 108000 1600 1780 1860 1800 900 910 913 1000, type: 0x40 flags: 0x5 ie. it just blindly stuffs the bogus hsync_end and htotal from the DTD into the transcoder timing registers, and the display works. I believe the (at least more modern) hardware will automagically terminate the hsync pulse when the timing generator reaches htotal, which again points that we should use the hblank size to determine htotal. Unfortunatley the old bug reports for the Dell machines are extremely lacking in useful details so we have no idea what kind of timings the VBIOS programmed into the hardware :( Let's just flip this quirk around and reduce the length of the sync pulse instead of extending the blanking period. This at least seems to be the correct thing to do on more modern hardware. And if any issues crop up on older hardware we need to debug them properly. v2: Add debug message breadcrumbs (Jani) Reviewed-by: Jani Nikula Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8895 Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20230920211934.14920-1-ville.syrjala@linux.intel.com Signed-off-by: Sasha Levin

drm/edid: add 8 bpc quirk to the BenQ GW2765

2023-10-16T15:08:49+00:00

The BenQ GW2765 reports that it supports higher (> 8) bpc modes, but when trying to set them we end up with a black screen. So, limit it to 8 bpc modes. Cc: stable@vger.kernel.org # 6.5+ Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2610 Reviewed-by: Harry Wentland Signed-off-by: Hamza Mahfooz Link: https://patchwork.freedesktop.org/patch/msgid/20231012184927.133137-1-hamza.mahfooz@amd.com

BackMerge tag 'v6.5-rc7' into drm-next

2023-08-23T21:26:06+00:00

Linux 6.5-rc7 This is needed for the CI stuff and the msm pull has fixes in it. Signed-off-by: Dave Airlie

Revert "drm/edid: Fix csync detailed mode parsing"

2023-08-17T11:39:12+00:00

This reverts commit ca62297b2085b5b3168bd891ca24862242c635a1. Commit ca62297b2085 ("drm/edid: Fix csync detailed mode parsing") fixed EDID detailed mode sync parsing. Unfortunately, there are quite a few displays out there that have bogus (zero) sync field that are broken by the change. Zero means analog composite sync, which is not right for digital displays, and the modes get rejected. Regardless, it used to work, and it needs to continue to work. Revert the change. Rejecting modes with analog composite sync was the part that fixed the gitlab issue 8146 [1]. We'll need to get back to the drawing board with that. [1] https://gitlab.freedesktop.org/drm/intel/-/issues/8146 Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8789 Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8930 Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9044 Fixes: ca62297b2085 ("drm/edid: Fix csync detailed mode parsing") Cc: Ville Syrjälä Cc: dri-devel@lists.freedesktop.org Cc: # v6.4+ Signed-off-by: Jani Nikula Acked-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20230815101907.2900768-1-jani.nikula@intel.com

drm/edid: Add quirk for OSVR HDK 2.0

2023-06-29T08:11:09+00:00

The OSVR virtual reality headset HDK 2.0 uses a different EDID vendor and device identifier than the HDK 1.1 - 1.4 headsets. Add the HDK 2.0 vendor and device identifier to the quirks table so that window managers do not try to display the desktop screen on the headset display. Closes: https://gitlab.freedesktop.org/drm/misc/-/issues/30 Signed-off-by: Ralph Campbell Tested-by: Ralph Campbell Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20230621061903.3422648-1-rcampbell@nvidia.com