From 3882dccf48f9fbe787b5df3187d708ef348ac860 Mon Sep 17 00:00:00 2001 From: Alan Maguire Date: Thu, 8 Aug 2024 16:05:57 +0100 Subject: bpf/bpf_get,set_sockopt: add option to set TCP-BPF sock ops flags Currently the only opportunity to set sock ops flags dictating which callbacks fire for a socket is from within a TCP-BPF sockops program. This is problematic if the connection is already set up as there is no further chance to specify callbacks for that socket. Add TCP_BPF_SOCK_OPS_CB_FLAGS to bpf_setsockopt() and bpf_getsockopt() to allow users to specify callbacks later, either via an iterator over sockets or via a socket-specific program triggered by a setsockopt() on the socket. Previous discussion on this here [1]. [1] https://lore.kernel.org/bpf/f42f157b-6e52-dd4d-3d97-9b86c84c0b00@oracle.com/ Signed-off-by: Alan Maguire Link: https://lore.kernel.org/r/20240808150558.1035626-2-alan.maguire@oracle.com Signed-off-by: Martin KaFai Lau --- include/uapi/linux/bpf.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux/bpf.h') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 35bcf52dbc65..e05b39e39c3f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2851,7 +2851,7 @@ union bpf_attr { * **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**, * **TCP_NODELAY**, **TCP_MAXSEG**, **TCP_WINDOW_CLAMP**, * **TCP_THIN_LINEAR_TIMEOUTS**, **TCP_BPF_DELACK_MAX**, - * **TCP_BPF_RTO_MIN**. + * **TCP_BPF_RTO_MIN**, **TCP_BPF_SOCK_OPS_CB_FLAGS**. * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. * * **IPPROTO_IPV6**, which supports the following *optname*\ s: * **IPV6_TCLASS**, **IPV6_AUTOFLOWLABEL**. @@ -7080,6 +7080,7 @@ enum { TCP_BPF_SYN = 1005, /* Copy the TCP header */ TCP_BPF_SYN_IP = 1006, /* Copy the IP[46] and TCP header */ TCP_BPF_SYN_MAC = 1007, /* Copy the MAC, IP[46], and TCP header */ + TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */ }; enum { -- cgit v1.2.3 From b0966c724584a5a9fd7fb529de19807c31f27a45 Mon Sep 17 00:00:00 2001 From: Dave Marchevsky Date: Tue, 13 Aug 2024 21:24:23 +0000 Subject: bpf: Support bpf_kptr_xchg into local kptr Currently, users can only stash kptr into map values with bpf_kptr_xchg(). This patch further supports stashing kptr into local kptr by adding local kptr as a valid destination type. When stashing into local kptr, btf_record in program BTF is used instead of btf_record in map to search for the btf_field of the local kptr. The local kptr specific checks in check_reg_type() only apply when the source argument of bpf_kptr_xchg() is local kptr. Therefore, we make the scope of the check explicit as the destination now can also be local kptr. Acked-by: Martin KaFai Lau Signed-off-by: Dave Marchevsky Signed-off-by: Amery Hung Link: https://lore.kernel.org/r/20240813212424.2871455-5-amery.hung@bytedance.com Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include/uapi/linux/bpf.h') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 35bcf52dbc65..e2629457d72d 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5519,11 +5519,12 @@ union bpf_attr { * **-EOPNOTSUPP** if the hash calculation failed or **-EINVAL** if * invalid arguments are passed. * - * void *bpf_kptr_xchg(void *map_value, void *ptr) + * void *bpf_kptr_xchg(void *dst, void *ptr) * Description - * Exchange kptr at pointer *map_value* with *ptr*, and return the - * old value. *ptr* can be NULL, otherwise it must be a referenced - * pointer which will be released when this helper is called. + * Exchange kptr at pointer *dst* with *ptr*, and return the old value. + * *dst* can be map value or local kptr. *ptr* can be NULL, otherwise + * it must be a referenced pointer which will be released when this helper + * is called. * Return * The old value of kptr (which can be NULL). The returned pointer * if not NULL, is a reference which must be released using its -- cgit v1.2.3 From 65ab5ac4df012388481d0414fcac1d5ac1721fb3 Mon Sep 17 00:00:00 2001 From: Jordan Rome Date: Fri, 23 Aug 2024 12:51:00 -0700 Subject: bpf: Add bpf_copy_from_user_str kfunc This adds a kfunc wrapper around strncpy_from_user, which can be called from sleepable BPF programs. This matches the non-sleepable 'bpf_probe_read_user_str' helper except it includes an additional 'flags' param, which allows consumers to clear the entire destination buffer on success or failure. Signed-off-by: Jordan Rome Link: https://lore.kernel.org/r/20240823195101.3621028-1-linux@jordanrome.com Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/uapi/linux/bpf.h') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index e2629457d72d..c3a5728db115 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -7513,4 +7513,13 @@ struct bpf_iter_num { __u64 __opaque[1]; } __attribute__((aligned(8))); +/* + * Flags to control BPF kfunc behaviour. + * - BPF_F_PAD_ZEROS: Pad destination buffer with zeros. (See the respective + * helper documentation for details.) + */ +enum bpf_kfunc_flags { + BPF_F_PAD_ZEROS = (1ULL << 0), +}; + #endif /* _UAPI__LINUX_BPF_H__ */ -- cgit v1.2.3