diff options
Diffstat (limited to 'drivers/cxl/core/mbox.c')
| -rw-r--r-- | drivers/cxl/core/mbox.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c index 704d6b313144..839207b627a8 100644 --- a/drivers/cxl/core/mbox.c +++ b/drivers/cxl/core/mbox.c @@ -218,6 +218,40 @@ static bool cxl_mem_raw_command_allowed(u16 opcode) return true; } +/** + * cxl_payload_from_user_allowed() - Check contents of in_payload. + * @opcode: The mailbox command opcode. + * @payload_in: Pointer to the input payload passed in from user space. + * + * Return: + * * true - payload_in passes check for @opcode. + * * false - payload_in contains invalid or unsupported values. + * + * The driver may inspect payload contents before sending a mailbox + * command from user space to the device. The intent is to reject + * commands with input payloads that are known to be unsafe. This + * check is not intended to replace the users careful selection of + * mailbox command parameters and makes no guarantee that the user + * command will succeed, nor that it is appropriate. + * + * The specific checks are determined by the opcode. + */ +static bool cxl_payload_from_user_allowed(u16 opcode, void *payload_in) +{ + switch (opcode) { + case CXL_MBOX_OP_SET_PARTITION_INFO: { + struct cxl_mbox_set_partition_info *pi = payload_in; + + if (pi->flags && CXL_SET_PARTITION_IMMEDIATE_FLAG) + return false; + break; + } + default: + break; + } + return true; +} + static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox, struct cxl_dev_state *cxlds, u16 opcode, size_t in_size, size_t out_size, u64 in_payload) @@ -232,6 +266,13 @@ static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox, in_size); if (!mbox->payload_in) return PTR_ERR(mbox->payload_in); + + if (!cxl_payload_from_user_allowed(opcode, mbox->payload_in)) { + dev_dbg(cxlds->dev, "%s: input payload not allowed\n", + cxl_mem_opcode_to_name(opcode)); + kvfree(mbox->payload_in); + return -EBUSY; + } } /* Prepare to handle a full payload for variable sized output */ |