CVE-2025-71305

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> drm/display/dp_mst: Add protection against 0 vcpi<br /> <br /> When releasing a timeslot there is a slight chance we may end up<br /> with the wrong payload mask due to overflow if the delayed_destroy_work<br /> ends up coming into play after a DP 2.1 monitor gets disconnected<br /> which causes vcpi to become 0 then we try to make the payload =<br /> ~BIT(vcpi - 1) which is a negative shift. VCPI id should never<br /> really be 0 hence skip changing the payload mask if VCPI is 0.<br /> <br /> Otherwise it leads to<br /> [515.287237] xe 0000:03:00.0: [drm:drm_dp_mst_get_port_malloc<br /> [drm_display_helper]] port ffff888126ce9000 (3)<br /> [515.287267] -----------[ cut here ]-----------<br /> [515.287268] UBSAN: shift-out-of-bounds in<br /> ../drivers/gpu/drm/display/drm_dp_mst_topology.c:4575:36<br /> [515.287271] shift exponent -1 is negative<br /> [515.287275] CPU: 7 UID: 0 PID: 3108 Comm: kworker/u64:33 Tainted: G<br /> S U 6.17.0-rc6-lgci-xe-xe-3795-3e79699fa1b216e92+ #1 PREEMPT(voluntary)<br /> [515.287279] Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER<br /> [515.287279] Hardware name: ASUS System Product Name/PRIME Z790-P<br /> WIFI, BIOS 1645 03/15/2024<br /> [515.287281] Workqueue: drm_dp_mst_wq drm_dp_delayed_destroy_work<br /> [drm_display_helper]<br /> [515.287303] Call Trace:<br /> [515.287304] <br /> [515.287306] dump_stack_lvl+0xc1/0xf0<br /> [515.287313] dump_stack+0x10/0x20<br /> [515.287316] __ubsan_handle_shift_out_of_bounds+0x133/0x2e0<br /> [515.287324] ? drm_atomic_get_private_obj_state+0x186/0x1d0<br /> [515.287333] drm_dp_atomic_release_time_slots.cold+0x17/0x3d<br /> [drm_display_helper]<br /> [515.287355] mst_connector_atomic_check+0x159/0x180 [xe]<br /> [515.287546] drm_atomic_helper_check_modeset+0x4d9/0xfa0<br /> [515.287550] ? __ww_mutex_lock.constprop.0+0x6f/0x1a60<br /> [515.287562] intel_atomic_check+0x119/0x2b80 [xe]<br /> [515.287740] ? find_held_lock+0x31/0x90<br /> [515.287747] ? lock_release+0xce/0x2a0<br /> [515.287754] drm_atomic_check_only+0x6a2/0xb40<br /> [515.287758] ? drm_atomic_add_affected_connectors+0x12b/0x140<br /> [515.287765] drm_atomic_commit+0x6e/0xf0<br /> [515.287766] ? _pfx__drm_printfn_info+0x10/0x10<br /> [515.287774] drm_client_modeset_commit_atomic+0x25c/0x2b0<br /> [515.287794] drm_client_modeset_commit_locked+0x60/0x1b0<br /> [515.287795] ? mutex_lock_nested+0x1b/0x30<br /> [515.287801] drm_client_modeset_commit+0x26/0x50<br /> [515.287804] __drm_fb_helper_restore_fbdev_mode_unlocked+0xdc/0x110<br /> [515.287810] drm_fb_helper_hotplug_event+0x120/0x140<br /> [515.287814] drm_fbdev_client_hotplug+0x28/0xd0<br /> [515.287819] drm_client_hotplug+0x6c/0xf0<br /> [515.287824] drm_client_dev_hotplug+0x9e/0xd0<br /> [515.287829] drm_kms_helper_hotplug_event+0x1a/0x30<br /> [515.287834] drm_dp_delayed_destroy_work+0x3df/0x410<br /> [drm_display_helper]<br /> [515.287861] process_one_work+0x22b/0x6f0<br /> [515.287874] worker_thread+0x1e8/0x3d0<br /> [515.287879] ? __pfx_worker_thread+0x10/0x10<br /> [515.287882] kthread+0x11c/0x250<br /> [515.287886] ? __pfx_kthread+0x10/0x10<br /> [515.287890] ret_from_fork+0x2d7/0x310<br /> [515.287894] ? __pfx_kthread+0x10/0x10<br /> [515.287897] ret_from_fork_asm+0x1a/0x30