Re: [PATCH] exec: do_close_on_exec() before taking exec_update_lock

[Christian Brauner]

On Mon, 07 Sep 2026 23:26:32 +0200, Jann Horn wrote:
> do_close_on_exec() currently happens while holding the exec_update_lock,
> which is used in a lot of places that access process state to
> synchronize access checks.
> I recently added another such use of exec_update_lock, causing a
> regression.
> 
> do_close_on_exec() can block waiting for a reply from a filesystem.
> That means a hung filesystem can block codepaths that use
> exec_update_lock; and it also means that a FUSE filesystem which
> attempts to inspect the calling process can deadlock.
> 
> [...]

Applied to the vfs.fixes branch of the vfs/vfs.git tree.
Patches in the vfs.fixes branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.fixes

[1/1] exec: do_close_on_exec() before taking exec_update_lock
      https://git.kernel.org/vfs/vfs/c/e780259b54e6