RE: [PATCH net-next] ixgbe: fix signed-integer-overflow warning

From: Kirsher, Jeffrey T
Date: Mon May 04 2020 - 22:44:20 EST


> -----Original Message-----
> From: Xie XiuQi <xiexiuqi@xxxxxxxxxx>
> Sent: Monday, May 4, 2020 19:45
> To: Kirsher, Jeffrey T <jeffrey.t.kirsher@xxxxxxxxx>; davem@xxxxxxxxxxxxx
> Cc: intel-wired-lan@xxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH net-next] ixgbe: fix signed-integer-overflow warning
>
> ubsan report this warning, fix it by adding a unsigned suffix.
>
> UBSAN: signed-integer-overflow in
> drivers/net/ethernet/intel/ixgbe/ixgbe_common.c:2246:26
> 65535 * 65537 cannot be represented in type 'int'
> CPU: 21 PID: 7 Comm: kworker/u256:0 Not tainted 5.7.0-rc3-debug+ #39
> Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2
> 03/27/2020
> Workqueue: ixgbe ixgbe_service_task [ixgbe] Call trace:
> dump_backtrace+0x0/0x3f0
> show_stack+0x28/0x38
> dump_stack+0x154/0x1e4
> ubsan_epilogue+0x18/0x60
> handle_overflow+0xf8/0x148
> __ubsan_handle_mul_overflow+0x34/0x48
> ixgbe_fc_enable_generic+0x4d0/0x590 [ixgbe]
> ixgbe_service_task+0xc20/0x1f78 [ixgbe]
> process_one_work+0x8f0/0xf18
> worker_thread+0x430/0x6d0
> kthread+0x218/0x238
> ret_from_fork+0x10/0x18
>
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Xie XiuQi <xiexiuqi@xxxxxxxxxx>
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe_common.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Dave, I am picking this up.