On Fri, Jun 26, 2026 at 6:09 PM Jakub Kicinski <[email protected]> wrote: > > On Thu, 25 Jun 2026 11:15:55 -0700 T.J. Mercier wrote: > > Write permissions on the /dev/udmabuf device file are not required to > > issue ioctls and allocate udmabufs. Applications should be opening this > > file as O_RDONLY. The BPF dmabuf_iter selftest already does this. [1] > > > > Remove the write access mode from the drivers/dma-buf/udmabuf.c and > > drivers/net/hw/ncdevmem.c selftests. > > You need to explain "why", too. Why change it if it clearly > worked for everyone running this test until now. > -- > pw-bot: cr
Principle of least privilege. Folks use or point to these selftests as examples, and then wonder why O_RDWR doesn't work on systems where write permissions are not available on /dev/udmabuf.
