Andrii Nakryiko 0ba971511d bpf: enforce types for __arg_ctx-tagged arguments in global subprogs ... Add enforcement of expected types for context arguments tagged with arg:ctx (__arg_ctx) tag. First, any program type will accept generic `void *` context type when combined with __arg_ctx tag. Besides accepting "canonical" struct names and `void *`, for a bunch of program types for which program context is actually a named struct, we allows a bunch of pragmatic exceptions to match real-world and expected usage: - for both kprobes and perf_event we allow `bpf_user_pt_regs_t *` as canonical context argument type, where `bpf_user_pt_regs_t` is a *typedef*, not a struct; - for kprobes, we also always accept `struct pt_regs *`, as that's what actually is passed as a context to any kprobe program; - for perf_event, we resolve typedefs (unless it's `bpf_user_pt_regs_t`) down to actual struct type and accept `struct pt_regs *`, or `struct user_pt_regs *`, or `struct user_regs_struct *`, depending on the actual struct type kernel architecture points `bpf_user_pt_regs_t` typedef to; otherwise, canonical `struct bpf_perf_event_data *` is expected; - for raw_tp/raw_tp.w programs, `u64/long *` are accepted, as that's what's expected with BPF_PROG() usage; otherwise, canonical `struct bpf_raw_tracepoint_args *` is expected; - tp_btf supports both `struct bpf_raw_tracepoint_args *` and `u64 *` formats, both are coded as expections as tp_btf is actually a TRACING program type, which has no canonical context type; - iterator programs accept `struct bpf_iter__xxx *` structs, currently with no further iterator-type specific enforcement; - fentry/fexit/fmod_ret/lsm/struct_ops all accept `u64 *`; - classic tracepoint programs, as well as syscall and freplace programs allow any user-provided type. In all other cases kernel will enforce exact match of struct name to expected canonical type. And if user-provided type doesn't match that expectation, verifier will emit helpful message with expected type name. Note a bit unnatural way the check is done after processing all the arguments. This is done to avoid conflict between bpf and bpf-next trees. Once trees converge, a small follow up patch will place a simple btf_validate_prog_ctx_type() check into a proper ARG_PTR_TO_CTX branch (which bpf-next tree patch refactored already), removing duplicated arg:ctx detection logic. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>		2024-01-17 20:20:06 -08:00
..
preload
arraymap.c
bloom_filter.c
bpf_cgrp_storage.c
bpf_inode_storage.c
bpf_iter.c
bpf_local_storage.c
bpf_lru_list.c
bpf_lru_list.h
bpf_lsm.c
bpf_struct_ops.c
bpf_struct_ops_types.h
bpf_task_storage.c
btf.c	bpf: enforce types for __arg_ctx-tagged arguments in global subprogs	2024-01-17 20:20:06 -08:00
cgroup.c
cgroup_iter.c
core.c
cpumap.c
cpumask.c
devmap.c
disasm.c
disasm.h
dispatcher.c
hashtab.c	Networking changes for 6.8.	2024-01-11 10:07:29 -08:00
helpers.c
inode.c
Kconfig
link_iter.c
local_storage.c
log.c
lpm_trie.c
Makefile
map_in_map.c
map_in_map.h
map_iter.c
memalloc.c	bpf: Remove unnecessary cpu == 0 check in memalloc	2024-01-04 10:18:14 -08:00
mmap_unlock_work.h
mprog.c
net_namespace.c
offload.c
percpu_freelist.c
percpu_freelist.h
prog_iter.c
queue_stack_maps.c
reuseport_array.c
ringbuf.c
stackmap.c
syscall.c	bpf: Fix re-attachment branch in bpf_tracing_prog_attach	2024-01-04 20:40:19 -08:00
sysfs_btf.c
task_iter.c
tcx.c
tnum.c
trampoline.c
verifier.c	bpf: Reject variable offset alu on PTR_TO_FLOW_KEYS	2024-01-16 17:12:29 +01:00