Commit 1ea0f912 authored by Anton Protopopov's avatar Anton Protopopov Committed by Alexei Starovoitov

bpf: Fix map permissions check

The map_lookup_and_delete_elem() function should check for both FMODE_CAN_WRITE
and FMODE_CAN_READ permissions because it returns a map element to user space.

Fixes: bd513cd0 ("bpf: add MAP_LOOKUP_AND_DELETE_ELEM syscall")
Signed-off-by: default avatarAnton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-5-a.s.protopopov@gmail.comSigned-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent efbc3b8f
...@@ -1472,7 +1472,8 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) ...@@ -1472,7 +1472,8 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr)
map = __bpf_map_get(f); map = __bpf_map_get(f);
if (IS_ERR(map)) if (IS_ERR(map))
return PTR_ERR(map); return PTR_ERR(map);
if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) { if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
err = -EPERM; err = -EPERM;
goto err_put; goto err_put;
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment