diff options
| author | Chenbo Feng <fengc@google.com> | 2018-03-19 17:57:27 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-28 18:39:26 +0200 |
| commit | 3eb88807b26daef1342d733d75956ad50d72b9d6 (patch) | |
| tree | 269be7dbd86b7ef0e7a997d77c928a701fb01ce1 | |
| parent | 733a4e1af803b1094b26040fc50e5c821fa2f28f (diff) | |
bpf: skip unnecessary capability check
commit 0fa4fe85f4724fff89b09741c437cbee9cf8b008 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 91a2d3752007..f8b4e3e16cef 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -801,7 +801,7 @@ 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; if (!access_ok(VERIFY_READ, uattr, 1)) |