From 1be84ca53ca0421c781f9ec007cd8bccbb58f763 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Fri, 6 Oct 2023 21:44:39 -0700 Subject: bpftool: Align bpf_load_and_run_opts insns and data A C string lacks alignment so use aligned arrays to avoid potential alignment problems. Switch to using sizeof (less 1 for the \0 terminator) rather than a hardcode size constant. Signed-off-by: Ian Rogers Signed-off-by: Andrii Nakryiko Acked-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20231007044439.25171-2-irogers@google.com --- tools/bpf/bpftool/gen.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 882bf8e6e70e..ee3ce2b8000d 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -708,17 +708,22 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h codegen("\ \n\ - skel->%1$s = skel_prep_map_data((void *)\"\\ \n\ - ", ident); + { \n\ + static const char data[] __attribute__((__aligned__(8))) = \"\\\n\ + "); mmap_data = bpf_map__initial_value(map, &mmap_size); print_hex(mmap_data, mmap_size); codegen("\ \n\ - \", %1$zd, %2$zd); \n\ - if (!skel->%3$s) \n\ - goto cleanup; \n\ - skel->maps.%3$s.initial_value = (__u64) (long) skel->%3$s;\n\ - ", bpf_map_mmap_sz(map), mmap_size, ident); + \"; \n\ + \n\ + skel->%1$s = skel_prep_map_data((void *)data, %2$zd,\n\ + sizeof(data) - 1);\n\ + if (!skel->%1$s) \n\ + goto cleanup; \n\ + skel->maps.%1$s.initial_value = (__u64) (long) skel->%1$s;\n\ + } \n\ + ", ident, bpf_map_mmap_sz(map)); } codegen("\ \n\ @@ -733,32 +738,30 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h { \n\ struct bpf_load_and_run_opts opts = {}; \n\ int err; \n\ - \n\ - opts.ctx = (struct bpf_loader_ctx *)skel; \n\ - opts.data_sz = %2$d; \n\ - opts.data = (void *)\"\\ \n\ + static const char opts_data[] __attribute__((__aligned__(8))) = \"\\\n\ ", - obj_name, opts.data_sz); + obj_name); print_hex(opts.data, opts.data_sz); codegen("\ \n\ \"; \n\ + static const char opts_insn[] __attribute__((__aligned__(8))) = \"\\\n\ "); - - codegen("\ - \n\ - opts.insns_sz = %d; \n\ - opts.insns = (void *)\"\\ \n\ - ", - opts.insns_sz); print_hex(opts.insns, opts.insns_sz); codegen("\ \n\ \"; \n\ + \n\ + opts.ctx = (struct bpf_loader_ctx *)skel; \n\ + opts.data_sz = sizeof(opts_data) - 1; \n\ + opts.data = (void *)opts_data; \n\ + opts.insns_sz = sizeof(opts_insn) - 1; \n\ + opts.insns = (void *)opts_insn; \n\ + \n\ err = bpf_load_and_run(&opts); \n\ if (err < 0) \n\ return err; \n\ - ", obj_name); + "); bpf_object__for_each_map(map, obj) { const char *mmap_flags; -- cgit v1.2.3