On 5/24/26 10:55 PM, Christoph Hellwig wrote:
On Fri, May 22, 2026 at 06:11:17PM -0700, John Hubbard wrote:
The dma-buf pseudo filesystem dispenses S_ANON_INODE inodes via alloc_anon_inode() but never sets SB_I_NOEXEC on its superblock. Since commit 1e7ab6f67824 ("anon_inode: rework assertions") in 6.17, path_noexec() warns on exactly that combination, so an mmap() on any dma-buf fd trips the warning:
Just as last time this came up, we really should set this higher up. There isn't really a reason why pseudofses should not set SB_I_NOEXEC by default.
Ha, I see now that there is some history to this.
After looking at the email history and the code, it does seem like the time is right to do that. I'm testing out a tiny series to set these flags in init_pseudo(), and then to *not* redundantly set them elsewhere, I'll post it shortly.
thanks,