staging: nvec: fix use-after-free in nvec_rx_completed()

In nvec_rx_completed(), when an incomplete RX transfer is detected,
nvec_msg_free() is called to return the message back to the pool by
clearing its 'used' atomic flag. Immediately after this, the code
accesses nvec->rx->data[0] to check the message type.

Since nvec_msg_free() marks the pool slot as available via atomic_set(),
any concurrent or subsequent call to nvec_msg_alloc() could claim that
same slot and overwrite its data[] array. Reading nvec->rx->data[0] after
freeing the message is therefore a use-after-free.

Fix this by saving the message type byte before calling nvec_msg_free(),
then using the saved value for the battery quirk check.

Fixes: d6bdcf2e1019 ("staging: nvec: Add battery quirk to ignore incomplete responses")
Reviewed-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Alexandru Hossu <hossu.alexandru@gmail.com>
Link: https://patch.msgid.link/20260427081713.3401874-2-hossu.alexandru@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions