From: Daniel Borkmann <daniel@iogearbox.net> stable inclusion from stable-v6.6.54 commit abf7559b4ff697714a6ca2600c16b02cfd75a2cb category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/ICL6PD Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 18752d73c1898fd001569195ba4b0b8c43255f4a ] When checking malformed helper function signatures, also take other argument types into account aside from just ARG_PTR_TO_UNINIT_MEM. This concerns (formerly) ARG_PTR_TO_{INT,LONG} given uninitialized memory can be passed there, too. The func proto sanity check goes back to commit 435faee1aae9 ("bpf, verifier: add ARG_PTR_TO_RAW_STACK type"), and its purpose was to detect wrong func protos which had more than just one MEM_UNINIT-tagged type as arguments. The reason more than one is currently not supported is as we mark stack slots with STACK_MISC in check_helper_call() in case of raw mode based on meta.access_size to allow uninitialized stack memory to be passed to helpers when they just write into the buffer. Probing for base type as well as MEM_UNINIT tagging ensures that other types do not get missed (as it used to be the case for ARG_PTR_TO_{INT,LONG}). Fixes: 57c3bb725a3d ("bpf: Introduce ARG_PTR_TO_{INT,LONG} arg types") Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20240913191754.13290-4-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> --- kernel/bpf/verifier.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index f87ceb4fa9d0..f0f50c5ff558 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8088,6 +8088,12 @@ static bool arg_type_is_mem_size(enum bpf_arg_type type) type == ARG_CONST_SIZE_OR_ZERO; } +static bool arg_type_is_raw_mem(enum bpf_arg_type type) +{ + return base_type(type) == ARG_PTR_TO_MEM && + type & MEM_UNINIT; +} + static bool arg_type_is_release(enum bpf_arg_type type) { return type & OBJ_RELEASE; @@ -9117,15 +9123,15 @@ static bool check_raw_mode_ok(const struct bpf_func_proto *fn) { int count = 0; - if (fn->arg1_type == ARG_PTR_TO_UNINIT_MEM) + if (arg_type_is_raw_mem(fn->arg1_type)) count++; - if (fn->arg2_type == ARG_PTR_TO_UNINIT_MEM) + if (arg_type_is_raw_mem(fn->arg2_type)) count++; - if (fn->arg3_type == ARG_PTR_TO_UNINIT_MEM) + if (arg_type_is_raw_mem(fn->arg3_type)) count++; - if (fn->arg4_type == ARG_PTR_TO_UNINIT_MEM) + if (arg_type_is_raw_mem(fn->arg4_type)) count++; - if (fn->arg5_type == ARG_PTR_TO_UNINIT_MEM) + if (arg_type_is_raw_mem(fn->arg5_type)) count++; /* We only support one arg being in raw mode at the moment, -- 2.34.1