[ Upstream commit 39ab8fff623053a50951b659e5f6b72343d7d78c ]
Commit 205c50306acf ("wifi: wilc1000: fix RCU usage in connect path")
made sure that the IEs data was manipulated under the relevant RCU section.
Unfortunately, while doing so, the commit brought a faulty implicit cast
from int to u8 on the ies_len variable, making the parsing fail to be
performed correctly if the IEs block is larger than 255 bytes. This failure
can be observed with Access Points appending a lot of IEs TLVs in their
beacon frames (reproduced with a Pixel phone acting as an Access Point,
which brough 273 bytes of IE data in my testing environment).
Fix IEs parsing by removing this undesired implicit cast.
Fixes: 205c50306acf ("wifi: wilc1000: fix RCU usage in connect path")
Signed-off-by: Jozef Hopko <jozef.hopko@altana.com>
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Acked-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/20240701-wilc_fix_ies_data-v1-1-7486cbacf98a@bootlin.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 205c50306acf58a335eb19fa84e40140f4fe814f ]
With lockdep enabled, calls to the connect function from cfg802.11 layer
lead to the following warning:
=============================
WARNING: suspicious RCU usage
6.7.0-rc1-wt+ #333 Not tainted
-----------------------------
drivers/net/wireless/microchip/wilc1000/hif.c:386
suspicious rcu_dereference_check() usage!
[...]
stack backtrace:
CPU: 0 PID: 100 Comm: wpa_supplicant Not tainted 6.7.0-rc1-wt+ #333
Hardware name: Atmel SAMA5
unwind_backtrace from show_stack+0x18/0x1c
show_stack from dump_stack_lvl+0x34/0x48
dump_stack_lvl from wilc_parse_join_bss_param+0x7dc/0x7f4
wilc_parse_join_bss_param from connect+0x2c4/0x648
connect from cfg80211_connect+0x30c/0xb74
cfg80211_connect from nl80211_connect+0x860/0xa94
nl80211_connect from genl_rcv_msg+0x3fc/0x59c
genl_rcv_msg from netlink_rcv_skb+0xd0/0x1f8
netlink_rcv_skb from genl_rcv+0x2c/0x3c
genl_rcv from netlink_unicast+0x3b0/0x550
netlink_unicast from netlink_sendmsg+0x368/0x688
netlink_sendmsg from ____sys_sendmsg+0x190/0x430
____sys_sendmsg from ___sys_sendmsg+0x110/0x158
___sys_sendmsg from sys_sendmsg+0xe8/0x150
sys_sendmsg from ret_fast_syscall+0x0/0x1c
This warning is emitted because in the connect path, when trying to parse
target BSS parameters, we dereference a RCU pointer whithout being in RCU
critical section.
Fix RCU dereference usage by moving it to a RCU read critical section. To
avoid wrapping the whole wilc_parse_join_bss_param under the critical
section, just use the critical section to copy ies data
Fixes: c460495ee072 ("staging: wilc1000: fix incorrent type in initializer")
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240105075733.36331-3-alexis.lothore@bootlin.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
