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bpf: Exempt CAP_BPF from checks against bpf_jit_limit

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When introducing CAP_BPF, bpf_jit_charge_modmem() was not changed to treat
programs with CAP_BPF as privileged for the purpose of JIT memory allocation.
This means that a program without CAP_BPF can block a program with CAP_BPF
from loading a program.

Fix this by checking bpf_capable() in bpf_jit_charge_modmem().

Fixes: 2c78ee898d ("bpf: Implement CAP_BPF")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210922111153.19843-1-lmb@cloudflare.com
This commit is contained in:
Lorenz Bauer 2021-09-22 12:11:52 +01:00 committed by Daniel Borkmann
parent 37cb28ec7d
commit 8a98ae12fb
1 changed files with 1 additions and 1 deletions
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2
kernel/bpf/core.c
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@ -827,7 +827,7 @@ int bpf_jit_charge_modmem(u32 pages)
{
if (atomic_long_add_return(pages, &bpf_jit_current) >
(bpf_jit_limit >> PAGE_SHIFT)) {
if (!capable(CAP_SYS_ADMIN)) {
if (!bpf_capable()) {
atomic_long_sub(pages, &bpf_jit_current);
return -EPERM;
}