{"schema":"threatline.record/2","record":{"id":"CVE-2026-99061","aliases":[],"summary":"wifi: brcmfmac: fix P2P device removal race in brcmf_detach()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: brcmfmac: fix P2P device removal race in brcmf_detach()\n\nWhen the driver is removed while the user space process that created\nthe P2P device (e.g. wpa_supplicant) is still exiting, the P2P device\ninterface is removed twice and the kernel crashes.\n\nThe two paths are:\n\n - wpa_supplicant, on exit, sends NL80211_CMD_DEL_INTERFACE for the P2P\n   device. nl80211_del_interface() holds RTNL and the wiphy mutex and\n   calls brcmf_p2p_del_vif(), which disables discovery and waits up to\n   1.5 s for BRCMF_E_IF_DEL. Then it calls brcmf_remove_interface(),\n   which unregisters the wdev and frees the vif and the ifp.\n\n - brcmf_detach() sets the bus down, so BRCMF_E_IF_DEL never arrives,\n   and calls brcmf_remove_interface(ifp, false) for the same ifp.\n   brcmf_p2p_ifp_removed() reads ifp->vif and then blocks on\n   rtnl_lock(). When brcmf_p2p_del_vif() releases RTNL, it calls\n   cfg80211_unregister_wdev() on the wdev that was already unregistered\n   and freed.\n\nThe second list_del_rcu() of wdev->list faults on LIST_POISON2:\n\n  brcmfmac: brcmf_p2p_del_vif delete P2P vif\n  brcmfmac: brcmf_p2p_deinit_discovery enter\n  brcmfmac: brcmf_p2p_del_vif P2P: GO_NEG_PHASE status cleared\n  brcmfmac: brcmf_detach Enter\n  brcmfmac: brcmf_bus_change_state 1 -> 0\n  brcmfmac: brcmf_remove_interface Enter, bsscfgidx=1, ifidx=0\n  brcmfmac: brcmf_del_if Enter, bsscfgidx=1, ifidx=0\n  brcmfmac: brcmf_p2p_ifp_removed P2P: device interface removed\n  [1.5 s later, brcmf_p2p_del_vif() timed out]\n  brcmfmac: brcmf_remove_interface Enter, bsscfgidx=1, ifidx=0\n  brcmfmac: brcmf_del_if Enter, bsscfgidx=1, ifidx=0\n  brcmfmac: brcmf_p2p_ifp_removed P2P: device interface removed\n  Unable to handle kernel paging request at virtual address dead000000000122\n  Internal error: Oops: 96000044 [#1] PREEMPT_RT SMP\n  pc : _cfg80211_unregister_wdev+0x6c/0x264 [cfg80211]\n  Call trace:\n   _cfg80211_unregister_wdev+0x6c/0x264 [cfg80211]\n   cfg80211_unregister_wdev+0x10/0x1c [cfg80211]\n   brcmf_p2p_ifp_removed+0x84/0xb0 [brcmfmac]\n   brcmf_remove_interface+0x1f4/0x254 [brcmfmac]\n   brcmf_detach+0x88/0x180 [brcmfmac]\n   brcmf_sdio_remove+0x90/0x7b0 [brcmfmac]\n   brcmf_sdiod_remove+0x20/0xa0 [brcmfmac]\n   brcmf_ops_sdio_remove+0xbc/0x12c [brcmfmac]\n   sdio_bus_remove+0x38/0x144\n   device_release_driver_internal+0x1e8/0x2c0\n   device_release_driver+0x14/0x20\n   brcmf_sdio_bus_remove+0x2c/0x40 [brcmfmac]\n   brcmf_fwvid_unregister_vendor+0xd8/0x170 [brcmfmac]\n   __exit_compat+0x18/0x418 [brcmfmac_cyw]\n   __arm64_sys_delete_module+0x1ac/0x244\n\nThe log was taken with debug=0x406 on an i.MX 8M Plus board with a\nCYW55513 (Sona IF513) on SDIO. The driver is the Ezurio backport of\nbrcmfmac from v6.18.22 on a 5.4-rt kernel. The code involved is the same\nin mainline.\n\nTo reproduce:\n\n  1. Start wpa_supplicant on wlan0 and let it associate. It creates the\n     P2P device (iw dev shows \"type P2P-device\").\n  2. Stop wpa_supplicant and remove the driver without waiting for\n     wpa_supplicant to exit:\n\n       kill $(pidof wpa_supplicant)\n       rmmod brcmfmac_cyw brcmfmac\n\nThe crash is reproducible on that board.\n\nFor the interface without a netdev (the P2P device), take RTNL and the\nwiphy mutex in brcmf_detach() before reading iflist, and remove it with\nlocked=true. If brcmf_p2p_del_vif() runs first, brcmf_detach() finds the\nslot empty. If brcmf_detach() runs first, nl80211 does not find the wdev\nany more. The interfaces with a netdev are removed as before, because\nbrcmf_del_if() takes RTNL on its own for the primary interface.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"9831bcb987df4aff6a1d85975f1dda4c654f298d","lessThan":"7b79131e357c4786765b20a994ad40d4d35f2163","status":"affected","versionType":"git"},{"version":"9831bcb987df4aff6a1d85975f1dda4c654f298d","lessThan":"2e0c8c60a11b3177e7432c71d41249e276a0825f","status":"affected","versionType":"git"},{"version":"9831bcb987df4aff6a1d85975f1dda4c654f298d","lessThan":"eef16a74ff8ed2a838d6bb862bb2c7783fce7466","status":"affected","versionType":"git"},{"version":"9831bcb987df4aff6a1d85975f1dda4c654f298d","lessThan":"47ca6395a1d91545cc9403f9218bc61be941a0c3","status":"affected","versionType":"git"},{"version":"9831bcb987df4aff6a1d85975f1dda4c654f298d","lessThan":"08a3f02fea636e97a7422d1512f76dacdb5b0887","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"4.4","status":"affected"},{"version":"0","lessThan":"4.4","status":"unaffected","versionType":"semver"},{"version":"6.6.160","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.113","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.57","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.11","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"7b79131e357c4786765b20a994ad40d4d35f2163","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"2e0c8c60a11b3177e7432c71d41249e276a0825f","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"47ca6395a1d91545cc9403f9218bc61be941a0c3","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","source_modified_at":"2026-10-23T12:22:59.770Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"08a3f02fea636e97a7422d1512f76dacdb5b0887","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-10-23T12:22:59.770Z","modified_at":"2026-10-23T12:22:59.770Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-99061","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T12:22:59.770Z"}],"sources":["CVE List"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/7b79131e357c4786765b20a994ad40d4d35f2163"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/2e0c8c60a11b3177e7432c71d41249e276a0825f"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/eef16a74ff8ed2a838d6bb862bb2c7783fce7466"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/47ca6395a1d91545cc9403f9218bc61be941a0c3"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/08a3f02fea636e97a7422d1512f76dacdb5b0887"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-23T12:22:59.770Z","content_hash":"559466a48eb395fb3bf562db17f6da59c6948484ed272eb550a7d52184ca0459"}}