diff options
| author | Anton Protopopov <a.s.protopopov@gmail.com> | 2020-05-27 18:56:59 +0000 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-06-01 14:38:21 -0700 |
| commit | 1ea0f9120c8ce105ca181b070561df5cbd6bc049 (patch) | |
| tree | 7e4c0c652d27f92872fc680e3dd06fb67548ec75 /kernel | |
| parent | efbc3b8fe1e6259777670aadf931500545073c6c (diff) | |
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: 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>
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 d13b804ff045..2c969a9b90d3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1472,7 +1472,8 @@ 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; } |