{"id":"AZL-108135","summary":"CVE-2026-98406 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: avoid WARN in set_bitrate_mask when sdata not in driver\n\nieee80211_set_bitrate_mask() checks if the interface is running via\nieee80211_sdata_running(), but it does not check if the interface is\nstill present in the driver.\n\nWhen sdata is running but IEEE80211_SDATA_IN_DRIVER is not set, the\ncall reaches drv_set_bitrate_mask() in driver-ops.h which hits\n\n  wlan1: Failed check-sdata-in-driver check, flags: 0x0\n  WARNING: net/mac80211/driver-ops.h:884 at drv_set_bitrate_mask\n\nSyzkaller triggers this via wext SIOCSIWRATE ioctl. The Call Trace shows\nwext_ioctl_dispatch() in wext-core.c dispatching the ioctl, calling\nioctl_standard_call() for SIOCSIWRATE, which calls cfg80211_wext_siwrate()\nin wext-compat.c. That builds a bitrate mask and calls\nrdev_set_bitrate_mask() which ends up in ieee80211_set_bitrate_mask() in\ncfg.c. The interface is marked running via SDATA_STATE_RUNNING but\nflags is 0, so check_sdata_in_driver() fails.\n\nWhen the interface is being torn down, or when wext ioctl is issued\nduring interface bringup before drv_add_interface() sets IN_DRIVER, the\nrunning check passes while IN_DRIVER is clear.\n\nCheck IEEE80211_SDATA_IN_DRIVER in ieee80211_set_bitrate_mask() before\ncalling the driver, returning -ENETDOWN. This avoids the WARN_ONCE in\ndriver-ops.h and matches other cfg.c operations that bail early when not\nin driver.\n\nThis change should be safe because wiphy mutex is held in\ncfg80211_wext_siwrate() via guard(wiphy), and IN_DRIVER is set/cleared\nunder RTNL and wiphy paths in drv_add_interface() and\ndrv_remove_interface() in driver-ops.c, so the check is race-free\nagainst driver add/remove. Returning -ENETDOWN is the same error other\nnot-running paths use and does not introduce new locking.\n\n[also add second syzbot report]","modified":"2026-10-15T14:17:17.048900784Z","published":"2026-10-14T14:17:51Z","upstream":["CVE-2026-98406"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98406"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-108135.json"}}],"schema_version":"1.9.0"}