[PATCH 5.11 112/254] bpf: Change inode_storages lookup_elem return value from NULL to -EBADF

[Greg Kroah-Hartman]

From: Tal Lossos <tallos...@gmail.com>

[ Upstream commit 769c18b254ca191b45047e1fcb3b2ce56fada0b6 ]

bpf_fd_inode_storage_lookup_elem() returned NULL when getting a bad FD,
which caused -ENOENT in bpf_map_copy_value. -EBADF error is better than
-ENOENT for a bad FD behaviour.

The patch was partially contributed by CyberArk Software, Inc.

Fixes: 8ea636848aca ("bpf: Implement bpf_local_storage for inodes")
Signed-off-by: Tal Lossos <tallos...@gmail.com>
Signed-off-by: Daniel Borkmann <dan...@iogearbox.net>
Acked-by: Yonghong Song <y...@fb.com>
Acked-by: KP Singh <kpsi...@kernel.org>
Link: https://lore.kernel.org/bpf/20210307120948.61414-1-tallos...@gmail.com
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 kernel/bpf/bpf_inode_storage.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c
index 6639640523c0..b58b2efb9b43 100644
--- a/kernel/bpf/bpf_inode_storage.c
+++ b/kernel/bpf/bpf_inode_storage.c
@@ -109,7 +109,7 @@ static void *bpf_fd_inode_storage_lookup_elem(struct 
bpf_map *map, void *key)
        fd = *(int *)key;
        f = fget_raw(fd);
        if (!f)
-               return NULL;
+               return ERR_PTR(-EBADF);
 
        sdata = inode_storage_lookup(f->f_inode, map, true);
        fput(f);
-- 
2.30.1