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[ciqlts8_6] bpf: Fix ringbuf memory type confusion when passing to helpers #371

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Merged
merged 1 commit into from
Jun 30, 2025
+12 −3
Merged

[ciqlts8_6] bpf: Fix ringbuf memory type confusion when passing to helpers #371

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9 changes: 7 additions & 2 deletions include/linux/bpf.h
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Original file line number Diff line number Diff line change
Expand Up @@ -296,7 +296,12 @@ enum bpf_type_flag {
*/
MEM_RDONLY = BIT(1 + BPF_BASE_TYPE_BITS),

__BPF_TYPE_LAST_FLAG = MEM_RDONLY,
/* MEM was "allocated" from a different helper, and cannot be mixed
* with regular non-MEM_ALLOC'ed MEM types.
*/
MEM_ALLOC = BIT(2 + BPF_BASE_TYPE_BITS),

__BPF_TYPE_LAST_FLAG = MEM_ALLOC,
};

/* Max number of base types. */
Expand Down Expand Up @@ -379,7 +384,7 @@ enum bpf_return_type {
RET_PTR_TO_SOCKET_OR_NULL = PTR_MAYBE_NULL | RET_PTR_TO_SOCKET,
RET_PTR_TO_TCP_SOCK_OR_NULL = PTR_MAYBE_NULL | RET_PTR_TO_TCP_SOCK,
RET_PTR_TO_SOCK_COMMON_OR_NULL = PTR_MAYBE_NULL | RET_PTR_TO_SOCK_COMMON,
RET_PTR_TO_ALLOC_MEM_OR_NULL = PTR_MAYBE_NULL | RET_PTR_TO_ALLOC_MEM,
RET_PTR_TO_ALLOC_MEM_OR_NULL = PTR_MAYBE_NULL | MEM_ALLOC | RET_PTR_TO_ALLOC_MEM,
RET_PTR_TO_BTF_ID_OR_NULL = PTR_MAYBE_NULL | RET_PTR_TO_BTF_ID,

/* This must be the last entry. Its purpose is to ensure the enum is
Expand Down
6 changes: 5 additions & 1 deletion kernel/bpf/verifier.c
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Original file line number Diff line number Diff line change
Expand Up @@ -574,6 +574,8 @@ static const char *reg_type_str(struct bpf_verifier_env *env,

if (type & MEM_RDONLY)
strncpy(prefix, "rdonly_", 16);
if (type & MEM_ALLOC)
strncpy(prefix, "alloc_", 16);

snprintf(env->type_str_buf, TYPE_STR_BUF_LEN, "%s%s%s",
prefix, str[base_type(type)], postfix);
Expand Down Expand Up @@ -4746,6 +4748,7 @@ static const struct bpf_reg_types mem_types = {
PTR_TO_MAP_KEY,
PTR_TO_MAP_VALUE,
PTR_TO_MEM,
PTR_TO_MEM | MEM_ALLOC,
PTR_TO_BUF,
},
};
Expand All @@ -4763,7 +4766,7 @@ static const struct bpf_reg_types int_ptr_types = {
static const struct bpf_reg_types fullsock_types = { .types = { PTR_TO_SOCKET } };
static const struct bpf_reg_types scalar_types = { .types = { SCALAR_VALUE } };
static const struct bpf_reg_types context_types = { .types = { PTR_TO_CTX } };
static const struct bpf_reg_types alloc_mem_types = { .types = { PTR_TO_MEM } };
static const struct bpf_reg_types alloc_mem_types = { .types = { PTR_TO_MEM | MEM_ALLOC } };
static const struct bpf_reg_types const_map_ptr_types = { .types = { CONST_PTR_TO_MAP } };
static const struct bpf_reg_types btf_ptr_types = { .types = { PTR_TO_BTF_ID } };
static const struct bpf_reg_types spin_lock_types = { .types = { PTR_TO_MAP_VALUE } };
Expand Down Expand Up @@ -4924,6 +4927,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
case PTR_TO_MAP_VALUE:
case PTR_TO_MEM:
case PTR_TO_MEM | MEM_RDONLY:
case PTR_TO_MEM | MEM_ALLOC:
case PTR_TO_BUF:
case PTR_TO_BUF | MEM_RDONLY:
case PTR_TO_STACK:
Expand Down