[PATCH AUTOSEL 6.1 01/12] NFSv4: Fix memory leak in nfs4_set_security_label

[PATCH AUTOSEL 6.1 01/12] NFSv4: Fix memory leak in nfs4_set_security_label

[Sasha Levin]

From: Dmitry Mastykin <mastichi@gmail.com>

[ Upstream commit aad11473f8f4be3df86461081ce35ec5b145ba68 ]

We leak nfs_fattr and nfs4_label every time we set a security xattr.

Signed-off-by: Dmitry Mastykin <mastichi@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfs/nfs4proc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index ec641a8f6604b..cc620fc7aaf7b 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6274,6 +6274,7 @@ nfs4_set_security_label(struct inode *inode, const void *buf, size_t buflen)
 	if (status == 0)
 		nfs_setsecurity(inode, fattr);
 
+	nfs_free_fattr(fattr);
 	return status;
 }
 #endif	/* CONFIG_NFS_V4_SECURITY_LABEL */
-- 
2.43.0

[PATCH AUTOSEL 6.1 02/12] nfs: propagate readlink errors in nfs_symlink_filler

[Sasha Levin]

From: Sagi Grimberg <sagi@grimberg.me>

[ Upstream commit 134d0b3f2440cdddd12fc3444c9c0f62331ce6fc ]

There is an inherent race where a symlink file may have been overriden
(by a different client) between lookup and readlink, resulting in a
spurious EIO error returned to userspace. Fix this by propagating back
ESTALE errors such that the vfs will retry the lookup/get_link (similar
to nfs4_file_open) at least once.

Cc: Dan Aloni <dan.aloni@vastdata.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfs/symlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c
index 0e27a2e4e68b8..13818129d268f 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -41,7 +41,7 @@ static int nfs_symlink_filler(struct file *file, struct folio *folio)
 error:
 	folio_set_error(folio);
 	folio_unlock(folio);
-	return -EIO;
+	return error;
 }
 
 static const char *nfs_get_link(struct dentry *dentry,
-- 
2.43.0

[PATCH AUTOSEL 6.1 03/12] nfs: don't invalidate dentries on transient errors

[Sasha Levin]

From: Scott Mayhew <smayhew@redhat.com>

[ Upstream commit 0c8c7c559740d2d8b66048162af6c4dba8f0c88c ]

This is a slight variation on a patch previously proposed by Neil Brown
that never got merged.

Prior to commit 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()"),
any error from nfs_lookup_verify_inode() other than -ESTALE would result
in nfs_lookup_revalidate() returning that error (-ESTALE is mapped to
zero).

Since that commit, all errors result in nfs_lookup_revalidate()
returning zero, resulting in dentries being invalidated where they
previously were not (particularly in the case of -ERESTARTSYS).

Fix it by passing the actual error code to nfs_lookup_revalidate_done(),
and leaving the decision on whether to  map the error code to zero or
one to nfs_lookup_revalidate_done().

A simple reproducer is to run the following python code in a
subdirectory of an NFS mount (not in the root of the NFS mount):

---8<---
import os
import multiprocessing
import time

if __name__=="__main__":
    multiprocessing.set_start_method("spawn")

    count = 0
    while True:
        try:
            os.getcwd()
            pool = multiprocessing.Pool(10)
            pool.close()
            pool.terminate()
            count += 1
        except Exception as e:
            print(f"Failed after {count} iterations")
            print(e)
            break
---8<---

Prior to commit 5ceb9d7fdaaf, the above code would run indefinitely.
After commit 5ceb9d7fdaaf, it fails almost immediately with -ENOENT.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfs/dir.c | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index a5a4d9422d6ed..70660ff248b79 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1615,7 +1615,16 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry,
 	switch (error) {
 	case 1:
 		break;
-	case 0:
+	case -ETIMEDOUT:
+		if (inode && (IS_ROOT(dentry) ||
+			      NFS_SERVER(inode)->flags & NFS_MOUNT_SOFTREVAL))
+			error = 1;
+		break;
+	case -ESTALE:
+	case -ENOENT:
+		error = 0;
+		fallthrough;
+	default:
 		/*
 		 * We can't d_drop the root of a disconnected tree:
 		 * its d_hash is on the s_anon list and d_drop() would hide
@@ -1670,18 +1679,8 @@ static int nfs_lookup_revalidate_dentry(struct inode *dir,
 
 	dir_verifier = nfs_save_change_attribute(dir);
 	ret = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr);
-	if (ret < 0) {
-		switch (ret) {
-		case -ESTALE:
-		case -ENOENT:
-			ret = 0;
-			break;
-		case -ETIMEDOUT:
-			if (NFS_SERVER(inode)->flags & NFS_MOUNT_SOFTREVAL)
-				ret = 1;
-		}
+	if (ret < 0)
 		goto out;
-	}
 
 	/* Request help from readdirplus */
 	nfs_lookup_advise_force_readdirplus(dir, flags);
@@ -1725,7 +1724,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
 			 unsigned int flags)
 {
 	struct inode *inode;
-	int error;
+	int error = 0;
 
 	nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
 	inode = d_inode(dentry);
@@ -1770,7 +1769,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
 out_bad:
 	if (flags & LOOKUP_RCU)
 		return -ECHILD;
-	return nfs_lookup_revalidate_done(dir, dentry, inode, 0);
+	return nfs_lookup_revalidate_done(dir, dentry, inode, error);
 }
 
 static int
-- 
2.43.0