From: Amery Hung <ameryhung@gmail.com> stable inclusion from stable-v6.6.121 commit 875d7cb4fe156d1a378bf38400e36797123ca9a6 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13686 CVE: CVE-2026-23140 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 7eb83bff02ad5e82e8c456c58717ef181c220870 ] Change the variable naming in bpf_prog_test_run_xdp() to make the overall logic less confusing. As different modes were added to the function over the time, some variables got overloaded, making it hard to understand and changing the code becomes error-prone. Replace "size" with "linear_sz" where it refers to the size of metadata and data. If "size" refers to input data size, use test.data_size_in directly. Replace "max_data_sz" with "max_linear_sz" to better reflect the fact that it is the maximum size of metadata and data (i.e., linear_sz). Also, xdp_rxq.frags_size is always PAGE_SIZE, so just set it directly instead of subtracting headroom and tailroom and adding them back. Signed-off-by: Amery Hung <ameryhung@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20250922233356.3356453-6-ameryhung@gmail.com Stable-dep-of: e558cca21779 ("bpf, test_run: Subtract size of xdp_frame from allowed metadata size") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Li Xiasong <lixiasong1@huawei.com> --- net/bpf/test_run.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 87b96b0d4c4e..10b4f3df014b 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -1149,9 +1149,9 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, { bool do_live = (kattr->test.flags & BPF_F_TEST_XDP_LIVE_FRAMES); u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + u32 retval = 0, duration, max_linear_sz, size; + u32 linear_sz = kattr->test.data_size_in; u32 batch_size = kattr->test.batch_size; - u32 retval = 0, duration, max_data_sz; - u32 size = kattr->test.data_size_in; u32 headroom = XDP_PACKET_HEADROOM; u32 repeat = kattr->test.repeat; struct netdev_rx_queue *rxqueue; @@ -1188,7 +1188,7 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, if (ctx) { /* There can't be user provided data before the meta data */ - if (ctx->data_meta || ctx->data_end != size || + if (ctx->data_meta || ctx->data_end != kattr->test.data_size_in || ctx->data > ctx->data_end || unlikely(xdp_metalen_invalid(ctx->data)) || (do_live && (kattr->test.data_out || kattr->test.ctx_out))) @@ -1197,30 +1197,30 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, headroom -= ctx->data; } - max_data_sz = PAGE_SIZE - headroom - tailroom; - if (size > max_data_sz) { - /* disallow live data mode for jumbo frames */ - if (do_live) - goto free_ctx; - size = max_data_sz; - } + max_linear_sz = PAGE_SIZE - headroom - tailroom; + linear_sz = min_t(u32, linear_sz, max_linear_sz); + + /* disallow live data mode for jumbo frames */ + if (do_live && kattr->test.data_size_in > linear_sz) + goto free_ctx; - data = bpf_test_init(kattr, size, max_data_sz, headroom, tailroom); + data = bpf_test_init(kattr, linear_sz, max_linear_sz, headroom, tailroom); if (IS_ERR(data)) { ret = PTR_ERR(data); goto free_ctx; } rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0); - rxqueue->xdp_rxq.frag_size = headroom + max_data_sz + tailroom; + rxqueue->xdp_rxq.frag_size = PAGE_SIZE; xdp_init_buff(&xdp, rxqueue->xdp_rxq.frag_size, &rxqueue->xdp_rxq); - xdp_prepare_buff(&xdp, data, headroom, size, true); + xdp_prepare_buff(&xdp, data, headroom, linear_sz, true); sinfo = xdp_get_shared_info_from_buff(&xdp); ret = xdp_convert_md_to_buff(ctx, &xdp); if (ret) goto free_data; + size = linear_sz; if (unlikely(kattr->test.data_size_in > size)) { void __user *data_in = u64_to_user_ptr(kattr->test.data_in); -- 2.34.1