From: Alexei Starovoitov Date: Tue, 20 Apr 2021 01:23:34 +0000 (-0700) Subject: Merge branch 'bpf: refine retval for bpf_get_task_stack helper' X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=69443c47305e541f5bf8b5a26f442c0c7f34cafe;p=linux.git Merge branch 'bpf: refine retval for bpf_get_task_stack helper' Dave Marchevsky says: ==================== Similarly to the bpf_get_stack helper, bpf_get_task_stack's return value can be more tightly bound by the verifier - it's the number of bytes written to a user-supplied buffer, or a negative error value. Currently the verifier believes bpf_task_get_stack's retval bounds to be unknown, requiring extraneous bounds checking to remedy. Adding it to do_refine_retval_range fixes the issue, as evidenced by new selftests which fail to load if retval bounds are not refined. v2: Addressed comment nit in patch 3 ==================== Signed-off-by: Alexei Starovoitov --- 69443c47305e541f5bf8b5a26f442c0c7f34cafe