io_uring/waitid: clear waitid info before copying it to userspace
3Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackepss 0.1%
exploitation probability
0.1%top 98% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
io_uring/waitid: clear waitid info before copying it to userspace
IORING_OP_WAITID stores its result fields in struct io_waitid::info and
later copies them to userspace siginfo. The prep path initializes the
request arguments, but it does not initialize info itself.
If the wait operation completes without reporting a child event, the common
wait code can return without writing wo_info. In that case io_waitid_finish()
still copies iw->info to userspace, exposing stale bytes from the reused
io_kiocb command storage.
Clear the result storage during prep so the io_uring path matches the
regular waitid syscall, which uses a zero-initialized struct waitid_info.
Affected products
Linux · Linux