android_kernel_xiaomi_sm7250/drivers/net/ethernet/rocker
Duoming Zhou 11f1e0c95e ethernet: rocker: fix sleep in atomic context bug in neigh_timer_handler
[ Upstream commit c0955bf957be4bead01fae1d791476260da7325d ]

The function neigh_timer_handler() is a timer handler that runs in an
atomic context. When used by rocker, neigh_timer_handler() calls
"kzalloc(.., GFP_KERNEL)" that may sleep. As a result, the sleep in
atomic context bug will happen. One of the processes is shown below:

ofdpa_fib4_add()
 ...
 neigh_add_timer()

(wait a timer)

neigh_timer_handler()
 neigh_release()
  neigh_destroy()
   rocker_port_neigh_destroy()
    rocker_world_port_neigh_destroy()
     ofdpa_port_neigh_destroy()
      ofdpa_port_ipv4_neigh()
       kzalloc(sizeof(.., GFP_KERNEL) //may sleep

This patch changes the gfp_t parameter of kzalloc() from GFP_KERNEL to
GFP_ATOMIC in order to mitigate the bug.

Fixes: 00fc0c51e3 ("rocker: Change world_ops API and implementation to be switchdev independant")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:17:02 +02:00
..
Kconfig
Makefile
rocker_hw.h
rocker_main.c
rocker_ofdpa.c
rocker_tlv.c
rocker_tlv.h
rocker.h