{"id":"CVE-2025-21976","summary":"fbdev: hyperv_fb: Allow graceful removal of framebuffer","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: hyperv_fb: Allow graceful removal of framebuffer\n\nWhen a Hyper-V framebuffer device is unbind, hyperv_fb driver tries to\nrelease the framebuffer forcefully. If this framebuffer is in use it\nproduce the following WARN and hence this framebuffer is never released.\n\n[   44.111220] WARNING: CPU: 35 PID: 1882 at drivers/video/fbdev/core/fb_info.c:70 framebuffer_release+0x2c/0x40\n\u003c snip \u003e\n[   44.111289] Call Trace:\n[   44.111290]  \u003cTASK\u003e\n[   44.111291]  ? show_regs+0x6c/0x80\n[   44.111295]  ? __warn+0x8d/0x150\n[   44.111298]  ? framebuffer_release+0x2c/0x40\n[   44.111300]  ? report_bug+0x182/0x1b0\n[   44.111303]  ? handle_bug+0x6e/0xb0\n[   44.111306]  ? exc_invalid_op+0x18/0x80\n[   44.111308]  ? asm_exc_invalid_op+0x1b/0x20\n[   44.111311]  ? framebuffer_release+0x2c/0x40\n[   44.111313]  ? hvfb_remove+0x86/0xa0 [hyperv_fb]\n[   44.111315]  vmbus_remove+0x24/0x40 [hv_vmbus]\n[   44.111323]  device_remove+0x40/0x80\n[   44.111325]  device_release_driver_internal+0x20b/0x270\n[   44.111327]  ? bus_find_device+0xb3/0xf0\n\nFix this by moving the release of framebuffer and assosiated memory\nto fb_ops.fb_destroy function, so that framebuffer framework handles\nit gracefully.\n\nWhile we fix this, also replace manual registrations/unregistration of\nframebuffer with devm_register_framebuffer.","aliases":["ECHO-55e2-e896-8f19"],"modified":"2026-04-21T02:27:09.101604612Z","published":"2025-04-01T15:47:07.120Z","related":["ALSA-2025:20095","SUSE-SU-2025:01600-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21976.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/4545e2aa121aea304d33903099c03e29ed4fe50a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a7b583dc99c6cf4a96877017be1d08247e1ef2c7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ea2f45ab0e53b255f72c85ccd99e2b394fc5fceb"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21976.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21976"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"68a2d20b79b105f02dcbc52c211d7e62f98996b7"},{"fixed":"4545e2aa121aea304d33903099c03e29ed4fe50a"},{"fixed":"a7b583dc99c6cf4a96877017be1d08247e1ef2c7"},{"fixed":"ea2f45ab0e53b255f72c85ccd99e2b394fc5fceb"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21976.json"}}],"schema_version":"1.7.5"}