iwl3945: fix possible il->txq NULL pointer dereference in delayed works
PATCH 1/1 iwl3945: fix possible il->txq NULL pointer dereference in delayed works
On il3945_down procedure we free tx queue data and nullify il->txq pointer. After that we drop mutex and then cancel delayed works. There is possibility, that after drooping mutex and before the cancel, some delayed work will start and crash while trying to send commands to the device. For example, here is reported crash in il3945_bg_reg_txpower_periodic():
https://bugzilla.kernel.org/show_bug.cgi?id=42766#c10
Patch fix problem by adding il->txq check on works that send commands, hence utilize tx queue.
Reported-by Clemens Eisserer <[email protected]>
Signed-off-by Stanislaw Gruszka <[email protected]>
--- drivers/net/wireless/iwlegacy/3945-mac.c | 2 +- drivers/net/wireless/iwlegacy/3945.c | 7 ++++--- 2 files changed, 5 insertions(+), 4 deletions(-)
drivers/net/wireless/iwlegacy/3945-mac.c +1 -1
@@ -2466,7 +2466,7 @@ il3945_bg_alive_start(struct work_struct *data) container_of(data, struct il_priv, alive_start.work);mutex_lock (&il->mutex); -if (test_bit (S_EXIT_PENDING , &il->status)) +if (test_bit (S_EXIT_PENDING , &il->status) || il->txq ==NULL ) goto out;il3945_alive_start (il);
drivers/net/wireless/iwlegacy/3945.c +4 -3
@@ -1855,11 +1855,12 @@ il3945_bg_reg_txpower_periodic(struct work_struct *work) struct il_priv *il = container_of(work, struct il_priv, _3945.thermal_periodic.work); -if (test_bit (S_EXIT_PENDING , &il->status)) -return ; -mutex_lock (&il->mutex); +if (test_bit (S_EXIT_PENDING , &il->status) || il->txq ==NULL ) + goto out; +il3945_reg_txpower_periodic (il); +out:mutex_unlock (&il->mutex); }
Signature · 1 line
1.7.1