From: Peilin Ye <yepeilin.cs@xxxxxxxxx> Date: Thu, 30 Jul 2020 15:20:26 -0400 > rds_notify_queue_get() is potentially copying uninitialized kernel stack > memory to userspace since the compiler may leave a 4-byte hole at the end > of `cmsg`. > > In 2016 we tried to fix this issue by doing `= { 0 };` on `cmsg`, which > unfortunately does not always initialize that 4-byte hole. Fix it by using > memset() instead. > > Cc: stable@xxxxxxxxxxxxxxx > Fixes: f037590fff30 ("rds: fix a leak of kernel memory") > Fixes: bdbe6fbc6a2f ("RDS: recv.c") > Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx> Applied and queued up for -stable, thanks. I saw a suggestion to use __packed but that breaks UAPI and is definitely not an option to solve this problem.