kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-10 20:48:12 +00:00
Code Issues Releases Packages Activity

nfs/localio: fix regression due to out-of-order __put_cred

Browse source 
commit 3af870aedb upstream.

Commit f2060bdc21 ("nfs/localio: add refcounting for each iocb IO
associated with NFS pgio header") inadvertantly reintroduced the same
potential for __put_cred() triggering BUG_ON(cred == current->cred) that
commit 992203a1fb ("nfs/localio: restore creds before releasing pageio
data") fixed.

Fix this by saving and restoring the cred around each {read,write}_iter
call within the respective for loop of nfs_local_call_{read,write} using
scoped_with_creds().

NOTE: this fix started by first reverting the following commits:

 94afb627df ("nfs: use credential guards in nfs_local_call_read()")
 bff3c841f7 ("nfs: use credential guards in nfs_local_call_write()")
 1d18101a64 ("Merge tag 'kernel-6.19-rc1.cred' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs")

followed by narrowly fixing the cred lifetime issue by using
scoped_with_creds().  In doing so, this commit's changes appear more
extensive than they really are (as evidenced by comparing to v6.18's
fs/nfs/localio.c).

Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Acked-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/linux-next/20251205111942.4150b06f@canb.auug.org.au/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mike Snitzer 2025-11-26 01:01:25 -05:00 • committed by Greg Kroah-Hartman
commit 7a28d65e4b
1 changed files with 6 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files