@@ -372,18 +372,10 @@ nfsd_file_put(struct nfsd_file *nf)
/* Try to add it to the LRU. If that fails, decrement. */
if (nfsd_file_lru_add(nf)) {
/* If it's still hashed, we're done */
- if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+ if (list_lru_count(&nfsd_file_lru))
nfsd_file_schedule_laundrette();
- return;
- }
- /*
- * We're racing with unhashing, so try to remove it from
- * the LRU. If removal fails, then someone else already
- * has our reference.
- */
- if (!nfsd_file_lru_remove(nf))
- return;
+ return;
}
}
if (refcount_dec_and_test(&nf->nf_ref))
In nfsd_file_put, after inserting the nfsd_file into the nfsd_file_lru list, gc may be triggered in another thread and immediately release this nfsd_file, which will lead to a UAF when accessing this nfsd_file again. All the places where unhash is done will also perform lru_remove, so there is no need to do lru_remove separately here. After inserting the nfsd_file into the nfsd_file_lru list, it can be released by relying on gc. Fixes: 4a0e73e635e3 ("NFSD: Leave open files out of the filecache LRU") Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> --- fs/nfsd/filecache.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-)