From: Jiri Pirko Add parsing and VA checks for blob descriptors shared by schema validation and runtime acquisition. Keep CONFIG_CTLV unwired until dispatch completes the module. Assisted-by: Cursor: GPT-5.6 Sol Assisted-by: Cursor: Claude Opus 5.5 Signed-off-by: Jiri Pirko --- drivers/ctlv/Makefile | 2 +- drivers/ctlv/blob_desc.c | 102 +++++++++++++++++++++++++++++++++++++++ drivers/ctlv/blob_desc.h | 29 +++++++++++ 3 files changed, 132 insertions(+), 1 deletion(-) create mode 100644 drivers/ctlv/blob_desc.c create mode 100644 drivers/ctlv/blob_desc.h diff --git a/drivers/ctlv/Makefile b/drivers/ctlv/Makefile index 4f0fe41bc9e1..5edc0b4b973f 100644 --- a/drivers/ctlv/Makefile +++ b/drivers/ctlv/Makefile @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_CTLV) += ctlv.o -ctlv-y += message.o +ctlv-y += blob_desc.o message.o diff --git a/drivers/ctlv/blob_desc.c b/drivers/ctlv/blob_desc.c new file mode 100644 index 000000000000..b84be3d723ab --- /dev/null +++ b/drivers/ctlv/blob_desc.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES + * + * Blob descriptor parsing and validation. + */ +#include +#include +#include +#include + +#include +#include + +#include "blob_desc.h" +#include "message.h" + +static int ctlv_blob_member(u64 attr_id) +{ + switch (attr_id) { + case CTLV_ATTR_BLOB_TYPE: + return CTLV_BLOB_MEMBER_TYPE; + case CTLV_ATTR_BLOB_ADDRESS: + return CTLV_BLOB_MEMBER_ADDRESS; + case CTLV_ATTR_BLOB_FD: + return CTLV_BLOB_MEMBER_FD; + case CTLV_ATTR_BLOB_OFFSET: + return CTLV_BLOB_MEMBER_OFFSET; + case CTLV_ATTR_BLOB_LENGTH: + return CTLV_BLOB_MEMBER_LENGTH; + default: + return -1; + } +} + +u32 ctlv_blob_desc_read(const struct ctlv_attr *blob, struct ctlv_blob_desc *desc, + const struct ctlv_attr **bad) +{ + const struct ctlv_attr *child = NULL; + enum ctlv_message_step step; + + *desc = (struct ctlv_blob_desc){}; + while ((step = ctlv_message_next(blob, &child)) == CTLV_MESSAGE_STEP_ATTR) { + int member = ctlv_blob_member(child->attr_id); + + *bad = child; + if (child->flags & ~CTLV_ATTR_F_NESTED) + return CTLV_VALIDATION_REASON_UNKNOWN_FLAG; + if (child->flags & CTLV_ATTR_F_NESTED) + return CTLV_VALIDATION_REASON_MALFORMED_MESSAGE; + if (member < 0) + return CTLV_VALIDATION_REASON_UNKNOWN_ATTR; + if (ctlv_message_attr_payload_len(child) != sizeof(u64)) + return CTLV_VALIDATION_REASON_BAD_LENGTH; + if (desc->present & BIT(member)) + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + desc->present |= BIT(member); + desc->member[member] = *(const u64 *)ctlv_message_attr_payload(child); + } + *bad = NULL; + if (step == CTLV_MESSAGE_STEP_BAD) + return CTLV_VALIDATION_REASON_MALFORMED_MESSAGE; + return 0; +} + +static u32 ctlv_blob_variant(const struct ctlv_blob_desc *desc) +{ + u32 required = BIT(CTLV_BLOB_MEMBER_TYPE) | BIT(CTLV_BLOB_MEMBER_LENGTH); + + switch (desc->member[CTLV_BLOB_MEMBER_TYPE]) { + case CTLV_BLOB_TYPE_VA: + required |= BIT(CTLV_BLOB_MEMBER_ADDRESS); + break; + default: + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + } + if (desc->present != required) + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + return 0; +} + +u32 ctlv_blob_desc_check(const struct ctlv_blob_desc *desc, const struct ctlv_node_schema *node) +{ + u64 start, length, end; + u32 reason; + + reason = ctlv_blob_variant(desc); + if (reason) + return reason; + if (!(node->blob.backings & BIT(desc->member[CTLV_BLOB_MEMBER_TYPE]))) + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + + length = desc->member[CTLV_BLOB_MEMBER_LENGTH]; + if (!length || length > node->blob.max_len) + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + start = desc->member[desc->present & BIT(CTLV_BLOB_MEMBER_ADDRESS) ? + CTLV_BLOB_MEMBER_ADDRESS : + CTLV_BLOB_MEMBER_OFFSET]; + if (!IS_ALIGNED(start, node->blob.alignment) || check_add_overflow(start, length, &end)) + return CTLV_VALIDATION_REASON_BAD_BLOB_DESCRIPTOR; + return 0; +} diff --git a/drivers/ctlv/blob_desc.h b/drivers/ctlv/blob_desc.h new file mode 100644 index 000000000000..27f77af16f01 --- /dev/null +++ b/drivers/ctlv/blob_desc.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _CTLV_BLOB_DESC_H +#define _CTLV_BLOB_DESC_H + +#include +#include + +#include + +/* The members of a descriptor, in the order the root family declares them. */ +enum { + CTLV_BLOB_MEMBER_TYPE, + CTLV_BLOB_MEMBER_ADDRESS, + CTLV_BLOB_MEMBER_FD, + CTLV_BLOB_MEMBER_OFFSET, + CTLV_BLOB_MEMBER_LENGTH, + CTLV_BLOB_MEMBERS, +}; + +struct ctlv_blob_desc { + u64 member[CTLV_BLOB_MEMBERS]; + u32 present; +}; + +u32 ctlv_blob_desc_read(const struct ctlv_attr *blob, struct ctlv_blob_desc *desc, + const struct ctlv_attr **bad); +u32 ctlv_blob_desc_check(const struct ctlv_blob_desc *desc, const struct ctlv_node_schema *node); + +#endif /* _CTLV_BLOB_DESC_H */ -- 2.56.0