| Message ID | 20230921120913.566702-4-daan.j.demeyer@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | Add cgroup sockaddr hooks for unix sockets | expand |
Hi Daan,
kernel test robot noticed the following build warnings:
[auto build test WARNING on bpf-next/master]
url: https://github.com/intel-lab-lkp/linux/commits/Daan-De-Meyer/selftests-bpf-Add-missing-section-name-tests-for-getpeername-getsockname/20230922-032515
base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link: https://lore.kernel.org/r/20230921120913.566702-4-daan.j.demeyer%40gmail.com
patch subject: [PATCH bpf-next v5 3/9] bpf: Add bpf_sock_addr_set_unix_addr() to allow writing unix sockaddr from bpf
config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20230923/202309231339.L2O0CrMU-lkp@intel.com/config)
compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230923/202309231339.L2O0CrMU-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309231339.L2O0CrMU-lkp@intel.com/
All warnings (new ones prefixed by >>):
net/core/filter.c:11731:17: warning: no previous declaration for 'bpf_dynptr_from_skb' [-Wmissing-declarations]
__bpf_kfunc int bpf_dynptr_from_skb(struct sk_buff *skb, u64 flags,
^~~~~~~~~~~~~~~~~~~
net/core/filter.c:11744:17: warning: no previous declaration for 'bpf_dynptr_from_xdp' [-Wmissing-declarations]
__bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_buff *xdp, u64 flags,
^~~~~~~~~~~~~~~~~~~
>> net/core/filter.c:11757:17: warning: no previous declaration for 'bpf_sock_addr_set_unix_addr' [-Wmissing-declarations]
__bpf_kfunc int bpf_sock_addr_set_unix_addr(struct bpf_sock_addr_kern *sa_kern,
^~~~~~~~~~~~~~~~~~~~~~~~~~~
net/core/filter.c:11860:17: warning: no previous declaration for 'bpf_sock_destroy' [-Wmissing-declarations]
__bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
^~~~~~~~~~~~~~~~
vim +/bpf_sock_addr_set_unix_addr +11757 net/core/filter.c
11756
11757 __bpf_kfunc int bpf_sock_addr_set_unix_addr(struct bpf_sock_addr_kern *sa_kern,
11758 const u8 *addr, u32 addrlen__sz)
11759 {
11760 struct sockaddr *sa = sa_kern->uaddr;
11761 struct sockaddr_un *un;
11762
11763 if (sa_kern->sk->sk_family != AF_UNIX)
11764 return -EINVAL;
11765
11766 /* We do not allow changing the address of unnamed unix sockets. */
11767 if (addrlen__sz == 0 || addrlen__sz > UNIX_PATH_MAX)
11768 return -EINVAL;
11769
11770 un = (struct sockaddr_un *)sa;
11771 memcpy(un->sun_path, addr, addrlen__sz);
11772 sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + addrlen__sz;
11773
11774 return 0;
11775 }
11776 __diag_pop();
11777
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index f93e835d90af..55765632059e 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -7850,6 +7850,7 @@ static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type) case BPF_PROG_TYPE_SYSCALL: return BTF_KFUNC_HOOK_SYSCALL; case BPF_PROG_TYPE_CGROUP_SKB: + case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: return BTF_KFUNC_HOOK_CGROUP_SKB; case BPF_PROG_TYPE_SCHED_ACT: return BTF_KFUNC_HOOK_SCHED_ACT; diff --git a/net/core/filter.c b/net/core/filter.c index a094694899c9..bd1c42b28483 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -81,6 +81,7 @@ #include <net/xdp.h> #include <net/mptcp.h> #include <net/netfilter/nf_conntrack_bpf.h> +#include <linux/un.h> static const struct bpf_func_proto * bpf_sk_base_func_proto(enum bpf_func_id func_id); @@ -11752,6 +11753,26 @@ __bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_buff *xdp, u64 flags, return 0; } + +__bpf_kfunc int bpf_sock_addr_set_unix_addr(struct bpf_sock_addr_kern *sa_kern, + const u8 *addr, u32 addrlen__sz) +{ + struct sockaddr *sa = sa_kern->uaddr; + struct sockaddr_un *un; + + if (sa_kern->sk->sk_family != AF_UNIX) + return -EINVAL; + + /* We do not allow changing the address of unnamed unix sockets. */ + if (addrlen__sz == 0 || addrlen__sz > UNIX_PATH_MAX) + return -EINVAL; + + un = (struct sockaddr_un *)sa; + memcpy(un->sun_path, addr, addrlen__sz); + sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + addrlen__sz; + + return 0; +} __diag_pop(); int bpf_dynptr_from_skb_rdonly(struct sk_buff *skb, u64 flags, @@ -11776,6 +11797,10 @@ BTF_SET8_START(bpf_kfunc_check_set_xdp) BTF_ID_FLAGS(func, bpf_dynptr_from_xdp) BTF_SET8_END(bpf_kfunc_check_set_xdp) +BTF_SET8_START(bpf_kfunc_check_set_sock_addr) +BTF_ID_FLAGS(func, bpf_sock_addr_set_unix_addr) +BTF_SET8_END(bpf_kfunc_check_set_sock_addr) + static const struct btf_kfunc_id_set bpf_kfunc_set_skb = { .owner = THIS_MODULE, .set = &bpf_kfunc_check_set_skb, @@ -11786,6 +11811,11 @@ static const struct btf_kfunc_id_set bpf_kfunc_set_xdp = { .set = &bpf_kfunc_check_set_xdp, }; +static const struct btf_kfunc_id_set bpf_kfunc_set_sock_addr = { + .owner = THIS_MODULE, + .set = &bpf_kfunc_check_set_sock_addr, +}; + static int __init bpf_kfunc_init(void) { int ret; @@ -11800,7 +11830,9 @@ static int __init bpf_kfunc_init(void) ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_XMIT, &bpf_kfunc_set_skb); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_SEG6LOCAL, &bpf_kfunc_set_skb); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_NETFILTER, &bpf_kfunc_set_skb); - return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp); + return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + &bpf_kfunc_set_sock_addr); } late_initcall(bpf_kfunc_init);
As prep for adding unix socket support to the cgroup sockaddr hooks, let's add a kfunc bpf_sock_addr_set_unix_addr() that allows modifying a sockaddr from bpf. While this is already possible for AF_INET and AF_INET6, we'll need this kfunc when we add unix socket support since modifying the address for those requires modifying both the address and the sockaddr length. Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> --- kernel/bpf/btf.c | 1 + net/core/filter.c | 34 +++++++++++++++++++++++++++++++++- 2 files changed, 34 insertions(+), 1 deletion(-)