diff options
author | Lorenz Bauer <lmb@cloudflare.com> | 2021-10-14 15:25:53 +0100 |
---|---|---|
committer | Michael Bestas <mkbestas@lineageos.org> | 2022-04-19 00:51:51 +0300 |
commit | f10e982d3b2ead1b049225b5bd8b149a43e3705b (patch) | |
tree | f2b0c94b3ec8991a4e7586457defbc5c747aee4e /kernel/bpf/core.c | |
parent | bfe07625deded524e7b7c68fdbe26dc0b8ada071 (diff) |
bpf: Prevent increasing bpf_jit_limit above max
[ Upstream commit fadb7ff1a6c2c565af56b4aacdd086b067eed440 ]
Restrict bpf_jit_limit to the maximum supported by the arch's JIT.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211014142554.53120-4-lmb@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/bpf/core.c')
-rw-r--r-- | kernel/bpf/core.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 8def8ae931d9..5c6f4cb9a6c2 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -212,6 +212,7 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON); int bpf_jit_harden __read_mostly; long bpf_jit_limit __read_mostly; +long bpf_jit_limit_max __read_mostly; static atomic_long_t bpf_jit_current; @@ -231,7 +232,8 @@ u64 __weak bpf_jit_alloc_exec_limit(void) static int __init bpf_jit_charge_init(void) { /* Only used as heuristic here to derive limit. */ - bpf_jit_limit = min_t(u64, round_up(bpf_jit_alloc_exec_limit() >> 2, + bpf_jit_limit_max = bpf_jit_alloc_exec_limit(); + bpf_jit_limit = min_t(u64, round_up(bpf_jit_limit_max >> 2, PAGE_SIZE), LONG_MAX); return 0; } |