iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: drop refcount if bpf_map_new_fd() fails in map_create()

Browse Source 
[ Upstream commit 352d20d611414715353ee65fc206ee57ab1a6984 ]

In bpf/syscall.c, map_create() first set map->usercnt to 1, a file
descriptor is supposed to return to userspace. When bpf_map_new_fd()
fails, drop the refcount.

Fixes: bd5f5f4ecb78 ("bpf: Add BPF_MAP_GET_FD_BY_ID")
Signed-off-by: Peng Sun <sironhide0null@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Peng Sun 2019-02-27 22:36:25 +08:00 committed by Greg Kroah-Hartman
parent 4e4a0cf997
commit ebf233fd40
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/bpf/syscall.c
View File

@ -348,12 +348,12 @@ static int map_create(union bpf_attr *attr)
err = bpf_map_new_fd(map);
if (err < 0) {
/* failed to allocate fd.
* bpf_map_put() is needed because the above
* bpf_map_put_with_uref() is needed because the above
* bpf_map_alloc_id() has published the map
* to the userspace and the userspace may
* have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
*/
bpf_map_put(map);
bpf_map_put_with_uref(map);
return err;
}