From: Al Viro <viro@zeniv.linux.org.uk>
To: Jeff Layton <jlayton@kernel.org>
Cc: linux-fsdevel@vger.kernel.org, agruenba@redhat.com,
amir73il@gmail.com, brauner@kernel.org,
ceph-devel@vger.kernel.org, dhowells@redhat.com,
hubcap@omnibond.com, jack@suse.cz, krisman@kernel.org,
linux-nfs@vger.kernel.org, miklos@szeredi.hu,
torvalds@linux-foundation.org
Subject: Re: [PATCH v2 07/20] Pass parent directory inode and expected name to ->d_revalidate()
Date: Fri, 17 Jan 2025 19:00:39 +0000 [thread overview]
Message-ID: <20250117190039.GR1977892@ZenIV> (raw)
In-Reply-To: <a345eacd1ec75dd5931b145e32f65e6725a26bf7.camel@kernel.org>
On Fri, Jan 17, 2025 at 01:55:01PM -0500, Jeff Layton wrote:
> > +static inline int d_revalidate(struct inode *dir, const struct qstr *name,
> > + struct dentry *dentry, unsigned int flags)
> > {
> > if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE))
> > - return dentry->d_op->d_revalidate(dentry, flags);
> > + return dentry->d_op->d_revalidate(dir, name, dentry, flags);
>
> I know I sent a R-b for this, but one question:
>
> Suppose we get back a positive result (dentry is still good), but the
> name and dentry->d_name no longer match. Do we need to do any special
> handling in that case?
Not really - it's the same situation we'd have if it got renamed right
after we'd concluded that everything's fine, after all. We can't spin
there indefinitely, rechecking the name for changes ;-)
In RCU mode ->d_seq mismatch guaranteed to catch that, in non-RCU...
well, there's really nothing we could do - rename could've bloody
well happened just as we'd completed pathname resolution.
next prev parent reply other threads:[~2025-01-17 19:00 UTC|newest]
Thread overview: 96+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-10 2:38 [PATCHES][RFC][CFT] ->d_revalidate() calling conventions changes (->d_parent/->d_name stability problems) Al Viro
2025-01-10 2:42 ` [PATCH 01/20] make sure that DNAME_INLINE_LEN is a multiple of word size Al Viro
2025-01-10 2:42 ` [PATCH 02/20] dcache: back inline names with a struct-wrapped array of unsigned long Al Viro
2025-01-10 9:35 ` Jan Kara
2025-01-10 16:24 ` Al Viro
2025-01-10 2:42 ` [PATCH 03/20] make take_dentry_name_snapshot() lockless Al Viro
2025-01-10 9:45 ` Jan Kara
2025-01-10 2:42 ` [PATCH 04/20] dissolve external_name.u into separate members Al Viro
2025-01-10 7:34 ` David Howells
2025-01-10 16:46 ` Al Viro
2025-01-10 2:42 ` [PATCH 05/20] ext4 fast_commit: make use of name_snapshot primitives Al Viro
2025-01-10 9:15 ` Jan Kara
2025-01-10 2:42 ` [PATCH 06/20] generic_ci_d_compare(): use shortname_storage Al Viro
2025-01-10 2:42 ` [PATCH 07/20] Pass parent directory inode and expected name to ->d_revalidate() Al Viro
2025-01-10 2:42 ` [PATCH 08/20] afs_d_revalidate(): use stable name and parent inode passed by caller Al Viro
2025-01-10 2:42 ` [PATCH 09/20] ceph_d_revalidate(): use stable " Al Viro
2025-01-10 19:45 ` Viacheslav Dubeyko
2025-01-10 2:42 ` [PATCH 10/20] ceph_d_revalidate(): propagate stable name down into request enconding Al Viro
2025-01-10 2:42 ` [PATCH 11/20] fscrypt_d_revalidate(): use stable parent inode passed by caller Al Viro
2025-01-10 2:42 ` [PATCH 12/20] exfat_d_revalidate(): " Al Viro
2025-01-10 2:42 ` [PATCH 13/20] vfat_revalidate{,_ci}(): " Al Viro
2025-01-10 2:42 ` [PATCH 14/20] fuse_dentry_revalidate(): use stable parent inode and name " Al Viro
2025-01-10 2:42 ` [PATCH 15/20] gfs2_drevalidate(): " Al Viro
2025-01-10 19:20 ` Andreas Grünbacher
2025-01-10 2:42 ` [PATCH 16/20] nfs{,4}_lookup_validate(): use stable parent inode " Al Viro
2025-01-10 2:43 ` [PATCH 17/20] nfs: fix ->d_revalidate() UAF on ->d_name accesses Al Viro
2025-01-10 2:43 ` [PATCH 18/20] ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller Al Viro
2025-01-10 9:54 ` Jan Kara
2025-01-10 2:43 ` [PATCH 19/20] orangefs_d_revalidate(): " Al Viro
2025-01-10 3:06 ` Linus Torvalds
2025-01-10 2:43 ` [PATCH 20/20] 9p: fix ->rename_sem exclusion Al Viro
2025-01-10 3:11 ` Linus Torvalds
2025-01-10 5:53 ` Al Viro
2025-01-10 9:21 ` [PATCH 01/20] make sure that DNAME_INLINE_LEN is a multiple of word size Jan Kara
2025-01-16 5:21 ` [PATCHES v2][RFC][CFT] ->d_revalidate() calling conventions changes (->d_parent/->d_name stability problems) Al Viro
2025-01-16 5:22 ` [PATCH v2 01/20] make sure that DNAME_INLINE_LEN is a multiple of word size Al Viro
2025-01-16 5:22 ` [PATCH v2 02/20] dcache: back inline names with a struct-wrapped array of unsigned long Al Viro
2025-01-16 5:23 ` [PATCH v2 03/20] make take_dentry_name_snapshot() lockless Al Viro
2025-01-16 5:23 ` [PATCH v2 04/20] dissolve external_name.u into separate members Al Viro
2025-01-16 10:06 ` Jan Kara
2025-01-16 5:23 ` [PATCH v2 05/20] ext4 fast_commit: make use of name_snapshot primitives Al Viro
2025-01-16 5:23 ` [PATCH v2 06/20] generic_ci_d_compare(): use shortname_storage Al Viro
2025-01-16 15:38 ` Gabriel Krisman Bertazi
2025-01-16 15:46 ` Al Viro
2025-01-16 15:53 ` Gabriel Krisman Bertazi
2025-01-16 5:23 ` [PATCH v2 07/20] Pass parent directory inode and expected name to ->d_revalidate() Al Viro
2025-01-16 15:15 ` Gabriel Krisman Bertazi
2025-01-17 18:55 ` Jeff Layton
2025-01-17 19:00 ` Al Viro [this message]
2025-01-16 5:23 ` [PATCH v2 08/20] afs_d_revalidate(): use stable name and parent inode passed by caller Al Viro
2025-01-22 20:27 ` David Howells
2025-01-22 21:01 ` Al Viro
2025-01-22 21:24 ` Al Viro
2025-01-22 21:55 ` David Howells
2025-01-16 5:23 ` [PATCH v2 09/20] ceph_d_revalidate(): use stable " Al Viro
2025-01-17 18:35 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 10/20] ceph_d_revalidate(): propagate stable name down into request enconding Al Viro
2025-01-17 18:35 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 11/20] fscrypt_d_revalidate(): use stable parent inode passed by caller Al Viro
2025-01-17 15:20 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 12/20] exfat_d_revalidate(): " Al Viro
2025-01-16 5:23 ` [PATCH v2 13/20] vfat_revalidate{,_ci}(): " Al Viro
2025-01-17 15:22 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 14/20] fuse_dentry_revalidate(): use stable parent inode and name " Al Viro
2025-01-17 15:18 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 15/20] gfs2_drevalidate(): " Al Viro
2025-01-16 5:23 ` [PATCH v2 16/20] nfs{,4}_lookup_validate(): use stable parent inode " Al Viro
2025-01-17 14:05 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 17/20] nfs: fix ->d_revalidate() UAF on ->d_name accesses Al Viro
2025-01-17 15:12 ` Jeff Layton
2025-01-16 5:23 ` [PATCH v2 18/20] ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller Al Viro
2025-01-16 5:23 ` [PATCH v2 19/20] orangefs_d_revalidate(): " Al Viro
2025-01-16 5:23 ` [PATCH v2 20/20] 9p: fix ->rename_sem exclusion Al Viro
2025-01-23 1:45 ` [PATCHES v3][RFC][CFT] ->d_revalidate() calling conventions changes (->d_parent/->d_name stability problems) Al Viro
2025-01-23 1:46 ` [PATCH v3 01/20] make sure that DNAME_INLINE_LEN is a multiple of word size Al Viro
2025-01-23 1:46 ` [PATCH v3 02/20] dcache: back inline names with a struct-wrapped array of unsigned long Al Viro
2025-01-23 1:46 ` [PATCH v3 03/20] make take_dentry_name_snapshot() lockless Al Viro
2025-01-23 1:46 ` [PATCH v3 04/20] dissolve external_name.u into separate members Al Viro
2025-01-23 1:46 ` [PATCH v3 05/20] ext4 fast_commit: make use of name_snapshot primitives Al Viro
2025-01-23 1:46 ` [PATCH v3 06/20] generic_ci_d_compare(): use shortname_storage Al Viro
2025-01-23 1:46 ` [PATCH v3 07/20] Pass parent directory inode and expected name to ->d_revalidate() Al Viro
2025-01-23 1:46 ` [PATCH v3 08/20] afs_d_revalidate(): use stable name and parent inode passed by caller Al Viro
2025-01-23 1:46 ` [PATCH v3 09/20] ceph_d_revalidate(): use stable " Al Viro
2025-01-23 1:46 ` [PATCH v3 10/20] ceph_d_revalidate(): propagate stable name down into request encoding Al Viro
2025-01-23 1:46 ` [PATCH v3 11/20] fscrypt_d_revalidate(): use stable parent inode passed by caller Al Viro
2025-01-23 1:46 ` [PATCH v3 12/20] exfat_d_revalidate(): " Al Viro
2025-01-23 1:46 ` [PATCH v3 13/20] vfat_revalidate{,_ci}(): " Al Viro
2025-01-23 1:46 ` [PATCH v3 14/20] fuse_dentry_revalidate(): use stable parent inode and name " Al Viro
2025-01-23 10:51 ` Miklos Szeredi
2025-01-23 1:46 ` [PATCH v3 15/20] gfs2_drevalidate(): " Al Viro
2025-01-23 1:46 ` [PATCH v3 16/20] nfs{,4}_lookup_validate(): use stable parent inode " Al Viro
2025-01-23 1:46 ` [PATCH v3 17/20] nfs: fix ->d_revalidate() UAF on ->d_name accesses Al Viro
2025-01-23 1:46 ` [PATCH v3 18/20] ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller Al Viro
2025-01-23 1:46 ` [PATCH v3 19/20] orangefs_d_revalidate(): " Al Viro
2025-01-25 16:25 ` Mike Marshall
2025-01-23 1:46 ` [PATCH v3 20/20] 9p: fix ->rename_sem exclusion Al Viro
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