wifi: nxpwifi: detach sync command buffer on interrupted wait

nxpwifi synchronous commands keep the caller-provided data buffer in
cmd_node->data_buf. Several callers pass stack-allocated objects there,
for example nxpwifi_get_chan_type() and the timeshare_coex debugfs
handlers.

If wait_event_interruptible_timeout() is interrupted or times out, the
caller can return and release that stack object while the command is still
current. nxpwifi_cancel_all_pending_cmd() deliberately keeps the current
command because a response may still arrive. A late firmware response can
then write through cmd_node->data_buf into the stale stack address.

After cancelling pending commands, detach the caller-owned buffer from the
still-current command under nxpwifi_cmd_lock.

Unlike the host command response path, several command response callbacks
do not tolerate a NULL data buffer. Most of them ignore it or check it
already, but nxpwifi_ret_sta_get_chan_info(),
nxpwifi_ret_sta_hs_wakeup_reason() and nxpwifi_ret_sta_robust_coex()
dereference it unconditionally, so let them discard a detached response.
No caller passes a NULL buffer to these commands today, so this only
affects the newly introduced detached state.

nxpwifi was derived from mwifiex before commit ef06882c7d ("wifi:
mwifiex: Detach sync cmd buffer on interrupted wait") and retains the same
lifetime bug. Apply the equivalent buffer detachment here.

Fixes: 73b01e57ed ("wifi: nxp: add nxpwifi driver for IW61x")
Signed-off-by: Linmao Li <lilinmao@kylinos.cn>
Link: https://patch.msgid.link/20260729124713.2849018-1-lilinmao@kylinos.cn
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Linmao Li 2026-07-29 20:47:13 +08:00 • committed by Johannes Berg
commit 068986fd6f
2 changed files with 22 additions and 0 deletions