diff options
| author | Chenbo Feng <fengc@google.com> | 2018-03-20 03:57:27 +0300 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-03-21 01:50:39 +0300 |
| commit | 0fa4fe85f4724fff89b09741c437cbee9cf8b008 (patch) | |
| tree | 38f02d936f9ef5b3e9fe9af90f8565c76d16e91a /kernel | |
| parent | f005afede992e265bb98534b86912bb669ccd0d2 (diff) | |
| download | linux-0fa4fe85f4724fff89b09741c437cbee9cf8b008.tar.xz | |
bpf: skip unnecessary capability check
The current check statement in BPF syscall will do a capability check
for CAP_SYS_ADMIN before checking sysctl_unprivileged_bpf_disabled. This
code path will trigger unnecessary security hooks on capability checking
and cause false alarms on unprivileged process trying to get CAP_SYS_ADMIN
access. This can be resolved by simply switch the order of the statement
and CAP_SYS_ADMIN is not required anyway if unprivileged bpf syscall is
allowed.
Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/syscall.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e24aa3241387..43f95d190eea 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1845,7 +1845,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz union bpf_attr attr = {}; int err; - if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled) + if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) return -EPERM; err = check_uarg_tail_zero(uattr, sizeof(attr), size); |