In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: usb: schedule rx work after everything is set up
Right now it’s possible to hit NULL pointer dereference in
rtw_rx_fill_rx_status on hw object and/or its fields because
initialization routine can start getting USB replies before
rtw_dev is fully setup.
The stack trace looks like this:
rtw_rx_fill_rx_status
rtw8821c_query_rx_desc
rtw_usb_rx_handler
…
queue_work
rtw_usb_read_port_complete
…
usb_submit_urb
rtw_usb_rx_resubmit
rtw_usb_init_rx
rtw_usb_probe
So while we do the async stuff rtw_usb_probe continues and calls
rtw_register_hw, which does all kinds of initialization (e.g.
via ieee80211_register_hw) that rtw_rx_fill_rx_status relies on.
Fix this by moving the first usb_submit_urb after everything
is set up.
For me, this bug manifested as:
[ 8.893177] rtw_8821cu 1-1:1.2: band wrong, packet dropped
[ 8.910904] rtw_8821cu 1-1:1.2: hw->conf.chandef.chan NULL in rtw_rx_fill_rx_status
because I’m using Larry’s backport of rtw88 driver with the NULL
checks in rtw_rx_fill_rx_status.
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/wireless/realtek/rtw88/usb.c"
],
"versions": [
{
"version": "1da177e4c3f4",
"lessThan": "c83d464b82a8",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f4",
"lessThan": "25eaef533bf3",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f4",
"lessThan": "adc539784c98",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/wireless/realtek/rtw88/usb.c"
],
"versions": [
{
"version": "6.6.51",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.10.10",
"lessThanOrEqual": "6.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.11",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]