[PATCH 0/2] Fix return with MSG_TUNC overtruncating buffers

[Gabriel Krisman Bertazi <krisman@suse.de>]

Jens,

This is an attempt to fix the issue reported at [1].  It works by
splitting the return size (which can be the full size of the packet)
from the value actually commited in the buffer.  Please, let me know
your thoughts.  Patch 1 is a small preparation and patch 2 has the fix.

This was tested for regressions against liburing as well as using the
reproducer from the bug, which I can turn into a proper test case
against liburing.

I sent this before but the submission was botched.  Please take this
version in consideration.

Thanks,

[1]  https://github.com/axboe/liburing/issues/1619

Gabriel Krisman Bertazi (2):
  io_uring/net: let io_recv_buf_select return the length of the buffer
    region
  io_uring/net: don't overconsume buffers when using MSG_TRUNC

 io_uring/net.c | 48 +++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 37 insertions(+), 11 deletions(-)

-- 
2.55.0