diff options
| author | Anton Protopopov <a.s.protopopov@gmail.com> | 2020-05-27 18:56:59 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-06-22 09:31:11 +0200 |
| commit | 215a256bc8dd7ef6bc52f3fd697027a7275d1c27 (patch) | |
| tree | 08fbc64518c9d9f7daabbd6d063c88af5fd3b52d /kernel | |
| parent | 0d55b7032ad1bde3a2e197c30a9f4c114c2b513d (diff) | |
bpf: Fix map permissions check
[ Upstream commit 1ea0f9120c8ce105ca181b070561df5cbd6bc049 ]
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: bd513cd08f10 ("bpf: add MAP_LOOKUP_AND_DELETE_ELEM syscall")
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-5-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/syscall.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 946cfdd3b2cc..e7af1ac69d75 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1118,7 +1118,8 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) map = __bpf_map_get(f); if (IS_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; goto err_put; } |