From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D7D7F3126BB for ; Mon, 8 Sep 2025 16:36:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757349419; cv=none; b=nJD46tzbR+nWyzSQdMcXbI8yGM7Sve4DB2g3H9vQzVdQeg/2Cjdle3jhyervsz8dHvKtdYZ3yKtkyl1y46Ga4EDa8T4mb++gDZna0QsMUr1c6+OljPV5/8R6X/oIZjVSWictUoQHfeDXYZd/Am65j/N8Mq/RooYIddPqBPafm5A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757349419; c=relaxed/simple; bh=tPFaiGQ9ipeWwto9ATZu8Uzn2irEud1LM+TyKGxlZr8=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SnBryT4XqxYIeJCsyhUBxpZG5xx3JNAx+rMyaMrBYH3kI5Fj1BA/xhfcdj5bTXIxMLFutgWlEw7tjDzA0jIsxUEhi2olQ87tiEv6phklLvKLpFdT8bTGyQg8Uphek8Kk4Pn4KvP82O+am6v6CGaqsM3ve4tk6xiEaNuOMz36zdM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CUuAZFHZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CUuAZFHZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6973FC4CEF1; Mon, 8 Sep 2025 16:36:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757349419; bh=tPFaiGQ9ipeWwto9ATZu8Uzn2irEud1LM+TyKGxlZr8=; h=From:To:Subject:Date:In-Reply-To:References:From; b=CUuAZFHZL5LizZpeffzVC/STCP6ymphXoxlyNRBbCFVcnQdy1x1r33TZ+Ehymp4f3 BonlgvQLa+mgSe+Js4SMSgLD7fH6EGECr5wM5v6S5OXjpHygIRefxHMWu3hlwFWHcb iNoZQ/Zx+UJZdM6hDKC2cJqo/e40Z+HEMyNo7st4AZv28Spwo0kWtb0PPJY/bO7rgD 2flOfqjoLGpnQWvveZVPUeTWyS7feGdTmwv5mcoIxU/sF3FeAIohZTGCiGm2wRfSfo mjCNr2nGeMg9mjI3C/vzt8wVGd0Vdm0gQfoWQxHabWFEWSM5vTD6o5JMldVG0LKss6 NxbcnlaAsFoJg== From: Puranjay Mohan To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Puranjay Mohan , Xu Kuohai , Catalin Marinas , Will Deacon , Kumar Kartikeya Dwivedi , bpf@vger.kernel.org Subject: [PATCH bpf-next v6 2/5] bpf: core: introduce main_prog_aux for stream access Date: Mon, 8 Sep 2025 16:36:31 +0000 Message-ID: <20250908163638.23150-3-puranjay@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20250908163638.23150-1-puranjay@kernel.org> References: <20250908163638.23150-1-puranjay@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit BPF streams are only valid for the main programs, to make it easier to access streams from subprogs, introduce main_prog_aux in struct bpf_prog_aux. prog->aux->main_prog_aux = prog->aux, for main programs and prog->aux->main_prog_aux = main_prog->aux, for subprograms. Make bpf_prog_find_from_stack() use the added main_prog_aux to return the mainprog when a subprog is found on the stack. Signed-off-by: Puranjay Mohan --- include/linux/bpf.h | 1 + kernel/bpf/core.c | 6 +++--- kernel/bpf/verifier.c | 1 + 3 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 8f6e87f0f3a89..d133171c4d2a9 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1633,6 +1633,7 @@ struct bpf_prog_aux { /* function name for valid attach_btf_id */ const char *attach_func_name; struct bpf_prog **func; + struct bpf_prog_aux *main_prog_aux; void *jit_data; /* JIT specific data. arch dependent */ struct bpf_jit_poke_descriptor *poke_tab; struct bpf_kfunc_desc_tab *kfunc_tab; diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index ef01cc644a965..c732737e6b735 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -120,6 +120,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag fp->pages = size / PAGE_SIZE; fp->aux = aux; + fp->aux->main_prog_aux = aux; fp->aux->prog = fp; fp->jit_requested = ebpf_jit_enabled(); fp->blinding_requested = bpf_jit_blinding_enabled(fp); @@ -3292,9 +3293,8 @@ static bool find_from_stack_cb(void *cookie, u64 ip, u64 sp, u64 bp) rcu_read_unlock(); if (!prog) return true; - if (bpf_is_subprog(prog)) - return true; - ctxp->prog = prog; + /* Make sure we return the main prog if we found a subprog */ + ctxp->prog = prog->aux->main_prog_aux->prog; return false; } diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b9394f8fac0ed..0162c5ad682ed 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -21597,6 +21597,7 @@ static int jit_subprogs(struct bpf_verifier_env *env) func[i]->aux->func_info_cnt = prog->aux->func_info_cnt; func[i]->aux->poke_tab = prog->aux->poke_tab; func[i]->aux->size_poke_tab = prog->aux->size_poke_tab; + func[i]->aux->main_prog_aux = prog->aux; for (j = 0; j < prog->aux->size_poke_tab; j++) { struct bpf_jit_poke_descriptor *poke; -- 2.47.3