{"cve":"CVE-2022-49070","nvd":{"published":"2025-02-26T07:00:44.217","modified":"2026-06-17T05:16:59.840","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: Fix unregistering of framebuffers without device\n\nOF framebuffers do not have an underlying device in the Linux\ndevice hierarchy. Do a regular unregister call instead of hot\nunplugging such a non-existing device. Fixes a NULL dereference.\nAn example error message on ppc64le is shown below.\n\n  BUG: Kernel NULL pointer dereference on read at 0x00000060\n  Faulting instruction address: 0xc00000000080dfa4\n  Oops: Kernel access of bad area, sig: 11 [#1]\n  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries\n  [...]\n  CPU: 2 PID: 139 Comm: systemd-udevd Not tainted 5.17.0-ae085d7f9365 #1\n  NIP:  c00000000080dfa4 LR: c00000000080df9c CTR: c000000000797430\n  REGS: c000000004132fe0 TRAP: 0300   Not tainted  (5.17.0-ae085d7f9365)\n  MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 28228282  XER: 20000000\n  CFAR: c00000000000c80c DAR: 0000000000000060 DSISR: 40000000 IRQMASK: 0\n  GPR00: c00000000080df9c c000000004133280 c00000000169d200 0000000000000029\n  GPR04: 00000000ffffefff c000000004132f90 c000000004132f88 0000000000000000\n  GPR08: c0000000015658f8 c0000000015cd200 c0000000014f57d0 0000000048228283\n  GPR12: 0000000000000000 c00000003fffe300 0000000020000000 0000000000000000\n  GPR16: 0000000000000000 0000000113fc4a40 0000000000000005 0000000113fcfb80\n  GPR20: 000001000f7283b0 0000000000000000 c000000000e4a588 c000000000e4a5b0\n  GPR24: 0000000000000001 00000000000a0000 c008000000db0168 c0000000021f6ec0\n  GPR28: c0000000016d65a8 c000000004b36460 0000000000000000 c0000000016d64b0\n  NIP [c00000000080dfa4] do_remove_conflicting_framebuffers+0x184/0x1d0\n  [c000000004133280] [c00000000080df9c] do_remove_conflicting_framebuffers+0x17c/0x1d0 (unreliable)\n  [c000000004133350] [c00000000080e4d0] remove_conflicting_framebuffers+0x60/0x150\n  [c0000000041333a0] [c00000000080e6f4] remove_conflicting_pci_framebuffers+0x134/0x1b0\n  [c000000004133450] [c008000000e70438] drm_aperture_remove_conflicting_pci_framebuffers+0x90/0x100 [drm]\n  [c000000004133490] [c008000000da0ce4] bochs_pci_probe+0x6c/0xa64 [bochs]\n  [...]\n  [c000000004133db0] [c00000000002aaa0] system_call_exception+0x170/0x2d0\n  [c000000004133e10] [c00000000000c3cc] system_call_common+0xec/0x250\n\nThe bug [1] was introduced by commit 27599aacbaef (\"fbdev: Hot-unplug\nfirmware fb devices on forced removal\"). Most firmware framebuffers\nhave an underlying platform device, which can be hot-unplugged\nbefore loading the native graphics driver. OF framebuffers do not\n(yet) have that device. Fix the code by unregistering the framebuffer\nas before without a hot unplug.\n\nTested with 5.17 on qemu ppc64le emulation.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/0f525289ff0ddeb380813bd81e0f9bdaaa1c9078","https://git.kernel.org/stable/c/2388f826cdc9af2651991adc0feb79de9bdf2232","https://git.kernel.org/stable/c/de33df481545974ba47c46f05194e769e4307843","https://git.kernel.org/stable/c/feed87ff122b1640c221d4dd559442ab2cd50bb1"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:59:48.811064707+00:00"},"epss":{"cve":"CVE-2022-49070","score":0.00261,"percentile":0.17954,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}