{"id":"CVE-2026-98523","revision":"553dcaf201af4e7cbea144f4ea831d87","records":[{"revision":"553dcaf201af4e7cbea144f4ea831d87","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98523","aliases":[],"title":"drm/client: fix restore of partially initialized client","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/client: fix restore of partially initialized client\n\nI got a null-ptr-deref report when closing a DRM file descriptor:\n\nWARNING: drivers/gpu/drm/drm_atomic.c:2031 at\n__drm_atomic_helper_set_config+0x18e/0x1b0 [drm]\n\nCall Trace:\ndrm_client_modeset_commit_atomic+0x16b/0x220 [drm]\ndrm_client_modeset_commit_locked+0x56/0x160 [drm]\ndrm_client_modeset_commit+0x21/0x40 [drm]\n__drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0x7b/0x80\ndrm_fbdev_client_restore+0xe/0x20 [drm_client_lib]\ndrm_client_dev_restore+0x9f/0xc0 [drm]\ndrm_release+0xc5/0xe0 [drm]\n\nThe warning is followed by a NULL pointer dereference:\n\nBUG: kernel NULL pointer dereference, address: 0000000000000008\n\nRIP:\n__drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0x41/0x80\n[drm_kms_helper]\n\nCall Trace:\ndrm_fbdev_client_restore+0xe/0x20 [drm_client_lib]\ndrm_client_dev_restore+0x9f/0xc0 [drm]\ndrm_release+0xc5/0xe0 [drm]\n__fput+0xdc/0x2b0\n__x64_sys_close+0x39/0x80\ndo_syscall_64+0x8d/0x460\nentry_SYSCALL_64_after_hwframe+0x76/0x7e\n\ndrm_client_register() adds the DRM client to the device client list\nbefore invoking the initial hotplug callback. If the hotplug callback\nfails, the client remains registered.\n\nFor the fbdev client, a failure during drm_fb_helper_initial_config()\ncauses the partially initialized fbdev helper to be cleaned up.\ndrm_fb_helper_fini() releases fb_helper->info and leaves it NULL.\n\nThe fbdev client therefore remains registered even though there is no\nfully initialized framebuffer device.\n\nLater, when userspace closes the DRM file descriptor, drm_release()\ncan invoke the restore callbacks of registered DRM clients:\n\ndrm_release()\ndrm_client_dev_restore()\ndrm_fbdev_client_restore()\ndrm_fb_helper_restore_fbdev_mode_unlocked()\n\ndrm_fbdev_client_restore() currently restores the fbdev state\nunconditionally. For a partially initialized fbdev client this can\nsubmit an incomplete modeset state and subsequently access fbdev\nstate which has not been initialized, resulting in the warning and\nNULL pointer dereference above.\n\ndrm_fbdev_client_unregister() already uses fb_helper->info to\ndistinguish a fully probed framebuffer device from a partially\ninitialized client.\n\nUse the same condition in drm_fbdev_client_restore() and skip restore\nif no framebuffer device has been successfully initialized.","state":0,"publishedAt":"2026-10-18T15:17:40.598+00:00","modifiedAt":"2026-10-19T09:21:05.087+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/gpu/drm/clients/drm_fbdev_client.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7f5535fcbba2ce7f1908ee7e5c350032a4b1e9d0\",\n                            \"lessThan\": \"11edd5b6735d2e1069ddce672b1836713647f7fb\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d08c44e47b9d41366714552bdd374ac4b595591\",\n                            \"lessThan\": \"fcbedba553a9c430079ee225df2dc7ab556a2f83\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d08c44e47b9d41366714552bdd374ac4b595591\",\n                            \"lessThan\": \"a69c4b678db808c0d89abb8cedeaaac38d1ef182\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d08c44e47b9d41366714552bdd374ac4b595591\",\n                            \"lessThan\": \"1fca688e9443003e33cf30453e7a7560367656c9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6.12.19\",\n                            \"lessThan\": \"6.12.112\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/gpu/drm/clients/drm_fbdev_client.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.13\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.13\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.112\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.55\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.9\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/11edd5b6735d2e1069ddce672b1836713647f7fb","https://git.kernel.org/stable/c/fcbedba553a9c430079ee225df2dc7ab556a2f83","https://git.kernel.org/stable/c/a69c4b678db808c0d89abb8cedeaaac38d1ef182","https://git.kernel.org/stable/c/1fca688e9443003e33cf30453e7a7560367656c9"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98523","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98523","identifiers":["CVE-2026-98523"]},"retained":false,"historicalAffected":[]}],"coverage":[]}