2020-01-26 22:33:53

by Trond Myklebust

Subject: [PATCH 2/3] NFS: nfs_access_get_cached_rcu() should use cred_fscmp()

We do not need to have the rcu lookup method fail in the case where
the fsuid/fsgid and supplemental groups match.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/dir.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index bfc66f3f00e1..6427a8a8d61a 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2360,7 +2360,7 @@ static int nfs_access_get_cached_rcu(struct inode *inode, const struct cred *cre
lh = rcu_dereference(nfsi->access_cache_entry_lru.prev);
cache = list_entry(lh, struct nfs_access_entry, lru);
if (lh == &nfsi->access_cache_entry_lru ||
- cred != cache->cred)
+ cred_fscmp(cred, cache->cred) != 0)
cache = NULL;
if (cache == NULL)
goto out;
--
2.24.1

2020-01-26 22:34:00

by Trond Myklebust

Subject: [PATCH 3/3] NFS: nfs_find_open_context() should use cred_fscmp()

We want to find open contexts that match our filesystem access
properties. They don't have to exactly match the cred.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 71dfc9d2fc3d..1309e6f47f3d 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1061,7 +1061,7 @@ struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct

rcu_read_lock();
list_for_each_entry_rcu(pos, &nfsi->open_files, list) {
- if (cred != NULL && pos->cred != cred)
+ if (cred != NULL && cred_fscmp(pos->cred, cred) != 0)
continue;
if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
continue;
--
2.24.1