This is a note to let you know that I've just added the patch titled
NFSD: Ensure nf_inode is never dereferenced
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsd-ensure-nf_inode-is-never-dereferenced.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 13482577e06debe2a13e3ea485cf556670c67cc1
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date: Fri Jul 8 14:27:09 2022 -0400
NFSD: Ensure nf_inode is never dereferenced
[ Upstream commit 427f5f83a3191cbf024c5aea6e5b601cdf88d895 ]
The documenting comment for struct nf_file states:
/*
* A representation of a file that has been opened by knfsd. These are hashed
* in the hashtable by inode pointer value. Note that this object doesn't
* hold a reference to the inode by itself, so the nf_inode pointer should
* never be dereferenced, only used for comparison.
*/
Replace the two existing dereferences to make the comment always
true.
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 7ad27655db699..55478d411e5a0 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -227,12 +227,11 @@ nfsd_file_mark_put(struct nfsd_file_mark *nfm)
}
static struct nfsd_file_mark *
-nfsd_file_mark_find_or_create(struct nfsd_file *nf)
+nfsd_file_mark_find_or_create(struct nfsd_file *nf, struct inode *inode)
{
int err;
struct fsnotify_mark *mark;
struct nfsd_file_mark *nfm = NULL, *new;
- struct inode *inode = nf->nf_inode;
do {
fsnotify_group_lock(nfsd_file_fsnotify_group);
@@ -1143,7 +1142,7 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
open_file:
trace_nfsd_file_alloc(nf);
- nf->nf_mark = nfsd_file_mark_find_or_create(nf);
+ nf->nf_mark = nfsd_file_mark_find_or_create(nf, key.inode);
if (nf->nf_mark) {
if (open) {
status = nfsd_open_verified(rqstp, fhp, may_flags,
diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h
index 28145f1628923..8e8c0c47d67df 100644
--- a/fs/nfsd/filecache.h
+++ b/fs/nfsd/filecache.h
@@ -39,7 +39,7 @@ struct nfsd_file {
#define NFSD_FILE_PENDING (1)
#define NFSD_FILE_REFERENCED (2)
unsigned long nf_flags;
- struct inode *nf_inode;
+ struct inode *nf_inode; /* don't deref */
refcount_t nf_ref;
unsigned char nf_may;
struct nfsd_file_mark *nf_mark;
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 923eec2716d75..9d344164f814f 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2577,7 +2577,7 @@ static void nfs4_show_fname(struct seq_file *s, struct nfsd_file *f)
static void nfs4_show_superblock(struct seq_file *s, struct nfsd_file *f)
{
- struct inode *inode = f->nf_inode;
+ struct inode *inode = file_inode(f->nf_file);
seq_printf(s, "superblock: \"%02x:%02x:%ld\"",
MAJOR(inode->i_sb->s_dev),
