diff options
author | Andres Beltran <lkmlabelt@gmail.com> | 2020-11-09 11:07:04 +0100 |
---|---|---|
committer | Wei Liu <wei.liu@kernel.org> | 2021-02-05 09:55:42 +0000 |
commit | 06caa778d8b2fbcb4ac3878751e39d116424ba9b (patch) | |
tree | f000d7887567b34e15a3193cf831589c5365c838 /drivers/hv | |
parent | a8c3209998afb5c4941b49e35b513cea9050cb4a (diff) | |
download | linux-06caa778d8b2fbcb4ac3878751e39d116424ba9b.tar.gz linux-06caa778d8b2fbcb4ac3878751e39d116424ba9b.tar.bz2 linux-06caa778d8b2fbcb4ac3878751e39d116424ba9b.zip |
hv_utils: Add validation for untrusted Hyper-V values
For additional robustness in the face of Hyper-V errors or malicious
behavior, validate all values that originate from packets that Hyper-V
has sent to the guest in the host-to-guest ring buffer. Ensure that
invalid values cannot cause indexing off the end of the icversion_data
array in vmbus_prep_negotiate_resp().
Signed-off-by: Andres Beltran <lkmlabelt@gmail.com>
Co-developed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20201109100704.9152-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/hv')
-rw-r--r-- | drivers/hv/channel_mgmt.c | 24 | ||||
-rw-r--r-- | drivers/hv/hv_fcopy.c | 36 | ||||
-rw-r--r-- | drivers/hv/hv_kvp.c | 122 | ||||
-rw-r--r-- | drivers/hv/hv_snapshot.c | 89 | ||||
-rw-r--r-- | drivers/hv/hv_util.c | 222 |
5 files changed, 306 insertions, 187 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 1d44bb635bb8..5bc5eef5da15 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -190,6 +190,7 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel) * vmbus_prep_negotiate_resp() - Create default response for Negotiate message * @icmsghdrp: Pointer to msg header structure * @buf: Raw buffer channel data + * @buflen: Length of the raw buffer channel data. * @fw_version: The framework versions we can support. * @fw_vercnt: The size of @fw_version. * @srv_version: The service versions we can support. @@ -202,8 +203,8 @@ static u16 hv_get_dev_type(const struct vmbus_channel *channel) * Set up and fill in default negotiate response message. * Mainly used by Hyper-V drivers. */ -bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, - u8 *buf, const int *fw_version, int fw_vercnt, +bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, u8 *buf, + u32 buflen, const int *fw_version, int fw_vercnt, const int *srv_version, int srv_vercnt, int *nego_fw_version, int *nego_srv_version) { @@ -215,10 +216,14 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, bool found_match = false; struct icmsg_negotiate *negop; + /* Check that there's enough space for icframe_vercnt, icmsg_vercnt */ + if (buflen < ICMSG_HDR + offsetof(struct icmsg_negotiate, reserved)) { + pr_err_ratelimited("Invalid icmsg negotiate\n"); + return false; + } + icmsghdrp->icmsgsize = 0x10; - negop = (struct icmsg_negotiate *)&buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + negop = (struct icmsg_negotiate *)&buf[ICMSG_HDR]; icframe_major = negop->icframe_vercnt; icframe_minor = 0; @@ -226,6 +231,15 @@ bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, icmsg_major = negop->icmsg_vercnt; icmsg_minor = 0; + /* Validate negop packet */ + if (icframe_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT || + icmsg_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT || + ICMSG_NEGOTIATE_PKT_SIZE(icframe_major, icmsg_major) > buflen) { + pr_err_ratelimited("Invalid icmsg negotiate - icframe_major: %u, icmsg_major: %u\n", + icframe_major, icmsg_major); + goto fw_error; + } + /* * Select the framework version number we will * support. diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c index 85784a9e6a36..660036da7449 100644 --- a/drivers/hv/hv_fcopy.c +++ b/drivers/hv/hv_fcopy.c @@ -235,15 +235,27 @@ void hv_fcopy_onchannelcallback(void *context) if (fcopy_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, - &requestid); - if (recvlen <= 0) + if (vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, &requestid)) { + pr_err_ratelimited("Fcopy request received. Could not read into recv buf\n"); return; + } + + if (!recvlen) + return; + + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("Fcopy request received. Packet length too small: %d\n", + recvlen); + return; + } icmsghdr = (struct icmsg_hdr *)&recv_buffer[ sizeof(struct vmbuspipe_hdr)]; + if (icmsghdr->icmsgtype == ICMSGTYPE_NEGOTIATE) { - if (vmbus_prep_negotiate_resp(icmsghdr, recv_buffer, + if (vmbus_prep_negotiate_resp(icmsghdr, + recv_buffer, recvlen, fw_versions, FW_VER_COUNT, fcopy_versions, FCOPY_VER_COUNT, NULL, &fcopy_srv_version)) { @@ -252,10 +264,14 @@ void hv_fcopy_onchannelcallback(void *context) fcopy_srv_version >> 16, fcopy_srv_version & 0xFFFF); } - } else { - fcopy_msg = (struct hv_fcopy_hdr *)&recv_buffer[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + } else if (icmsghdr->icmsgtype == ICMSGTYPE_FCOPY) { + /* Ensure recvlen is big enough to contain hv_fcopy_hdr */ + if (recvlen < ICMSG_HDR + sizeof(struct hv_fcopy_hdr)) { + pr_err_ratelimited("Invalid Fcopy hdr. Packet length too small: %u\n", + recvlen); + return; + } + fcopy_msg = (struct hv_fcopy_hdr *)&recv_buffer[ICMSG_HDR]; /* * Stash away this global state for completing the @@ -280,6 +296,10 @@ void hv_fcopy_onchannelcallback(void *context) schedule_delayed_work(&fcopy_timeout_work, HV_UTIL_TIMEOUT * HZ); return; + } else { + pr_err_ratelimited("Fcopy request received. Invalid msg type: %d\n", + icmsghdr->icmsgtype); + return; } icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE; vmbus_sendpacket(channel, recv_buffer, recvlen, requestid, diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c index 7d2a7b918847..c698592b83e4 100644 --- a/drivers/hv/hv_kvp.c +++ b/drivers/hv/hv_kvp.c @@ -662,71 +662,87 @@ void hv_kvp_onchannelcallback(void *context) if (kvp_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 4, &recvlen, - &requestid); - - if (recvlen > 0) { - icmsghdrp = (struct icmsg_hdr *)&recv_buffer[ - sizeof(struct vmbuspipe_hdr)]; - - if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { - if (vmbus_prep_negotiate_resp(icmsghdrp, - recv_buffer, fw_versions, FW_VER_COUNT, - kvp_versions, KVP_VER_COUNT, - NULL, &kvp_srv_version)) { - pr_info("KVP IC version %d.%d\n", - kvp_srv_version >> 16, - kvp_srv_version & 0xFFFF); - } - } else { - kvp_msg = (struct hv_kvp_msg *)&recv_buffer[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + if (vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 4, &recvlen, &requestid)) { + pr_err_ratelimited("KVP request received. Could not read into recv buf\n"); + return; + } - /* - * Stash away this global state for completing the - * transaction; note transactions are serialized. - */ + if (!recvlen) + return; - kvp_transaction.recv_len = recvlen; - kvp_transaction.recv_req_id = requestid; - kvp_transaction.kvp_msg = kvp_msg; + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("KVP request received. Packet length too small: %d\n", + recvlen); + return; + } - if (kvp_transaction.state < HVUTIL_READY) { - /* Userspace is not registered yet */ - kvp_respond_to_host(NULL, HV_E_FAIL); - return; - } - kvp_transaction.state = HVUTIL_HOSTMSG_RECEIVED; + icmsghdrp = (struct icmsg_hdr *)&recv_buffer[sizeof(struct vmbuspipe_hdr)]; + + if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { + if (vmbus_prep_negotiate_resp(icmsghdrp, + recv_buffer, recvlen, + fw_versions, FW_VER_COUNT, + kvp_versions, KVP_VER_COUNT, + NULL, &kvp_srv_version)) { + pr_info("KVP IC version %d.%d\n", + kvp_srv_version >> 16, + kvp_srv_version & 0xFFFF); + } + } else if (icmsghdrp->icmsgtype == ICMSGTYPE_KVPEXCHANGE) { + /* + * recvlen is not checked against sizeof(struct kvp_msg) because kvp_msg contains + * a union of structs and the msg type received is not known. Code using this + * struct should provide validation when accessing its fields. + */ + kvp_msg = (struct hv_kvp_msg *)&recv_buffer[ICMSG_HDR]; - /* - * Get the information from the - * user-mode component. - * component. This transaction will be - * completed when we get the value from - * the user-mode component. - * Set a timeout to deal with - * user-mode not responding. - */ - schedule_work(&kvp_sendkey_work); - schedule_delayed_work(&kvp_timeout_work, - HV_UTIL_TIMEOUT * HZ); + /* + * Stash away this global state for completing the + * transaction; note transactions are serialized. + */ - return; + kvp_transaction.recv_len = recvlen; + kvp_transaction.recv_req_id = requestid; + kvp_transaction.kvp_msg = kvp_msg; + if (kvp_transaction.state < HVUTIL_READY) { + /* Userspace is not registered yet */ + kvp_respond_to_host(NULL, HV_E_FAIL); + return; } + kvp_transaction.state = HVUTIL_HOSTMSG_RECEIVED; - icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION - | ICMSGHDRFLAG_RESPONSE; + /* + * Get the information from the + * user-mode component. + * component. This transaction will be + * completed when we get the value from + * the user-mode component. + * Set a timeout to deal with + * user-mode not responding. + */ + schedule_work(&kvp_sendkey_work); + schedule_delayed_work(&kvp_timeout_work, + HV_UTIL_TIMEOUT * HZ); - vmbus_sendpacket(channel, recv_buffer, - recvlen, requestid, - VM_PKT_DATA_INBAND, 0); + return; - host_negotiatied = NEGO_FINISHED; - hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper); + } else { + pr_err_ratelimited("KVP request received. Invalid msg type: %d\n", + icmsghdrp->icmsgtype); + return; } + icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION + | ICMSGHDRFLAG_RESPONSE; + + vmbus_sendpacket(channel, recv_buffer, + recvlen, requestid, + VM_PKT_DATA_INBAND, 0); + + host_negotiatied = NEGO_FINISHED; + hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper); } static void kvp_on_reset(void) diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c index 783779e4cc1a..2267bd4c3472 100644 --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -298,49 +298,64 @@ void hv_vss_onchannelcallback(void *context) if (vss_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, - &requestid); - - if (recvlen > 0) { - icmsghdrp = (struct icmsg_hdr *)&recv_buffer[ - sizeof(struct vmbuspipe_hdr)]; - - if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { - if (vmbus_prep_negotiate_resp(icmsghdrp, - recv_buffer, fw_versions, FW_VER_COUNT, - vss_versions, VSS_VER_COUNT, - NULL, &vss_srv_version)) { - - pr_info("VSS IC version %d.%d\n", - vss_srv_version >> 16, - vss_srv_version & 0xFFFF); - } - } else { - vss_msg = (struct hv_vss_msg *)&recv_buffer[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; - - /* - * Stash away this global state for completing the - * transaction; note transactions are serialized. - */ - - vss_transaction.recv_len = recvlen; - vss_transaction.recv_req_id = requestid; - vss_transaction.msg = (struct hv_vss_msg *)vss_msg; - - schedule_work(&vss_handle_request_work); + if (vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, &requestid)) { + pr_err_ratelimited("VSS request received. Could not read into recv buf\n"); + return; + } + + if (!recvlen) + return; + + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("VSS request received. Packet length too small: %d\n", + recvlen); + return; + } + + icmsghdrp = (struct icmsg_hdr *)&recv_buffer[sizeof(struct vmbuspipe_hdr)]; + + if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { + if (vmbus_prep_negotiate_resp(icmsghdrp, + recv_buffer, recvlen, + fw_versions, FW_VER_COUNT, + vss_versions, VSS_VER_COUNT, + NULL, &vss_srv_version)) { + + pr_info("VSS IC version %d.%d\n", + vss_srv_version >> 16, + vss_srv_version & 0xFFFF); + } + } else if (icmsghdrp->icmsgtype == ICMSGTYPE_VSS) { + /* Ensure recvlen is big enough to contain hv_vss_msg */ + if (recvlen < ICMSG_HDR + sizeof(struct hv_vss_msg)) { + pr_err_ratelimited("Invalid VSS msg. Packet length too small: %u\n", + recvlen); return; } + vss_msg = (struct hv_vss_msg *)&recv_buffer[ICMSG_HDR]; + + /* + * Stash away this global state for completing the + * transaction; note transactions are serialized. + */ - icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION - | ICMSGHDRFLAG_RESPONSE; + vss_transaction.recv_len = recvlen; + vss_transaction.recv_req_id = requestid; + vss_transaction.msg = (struct hv_vss_msg *)vss_msg; - vmbus_sendpacket(channel, recv_buffer, - recvlen, requestid, - VM_PKT_DATA_INBAND, 0); + schedule_work(&vss_handle_request_work); + return; + } else { + pr_err_ratelimited("VSS request received. Invalid msg type: %d\n", + icmsghdrp->icmsgtype); + return; } + icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | + ICMSGHDRFLAG_RESPONSE; + vmbus_sendpacket(channel, recv_buffer, recvlen, requestid, + VM_PKT_DATA_INBAND, 0); } static void vss_on_reset(void) diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c index 05566ecdbe4b..34f3e789cc9a 100644 --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -195,73 +195,88 @@ static void shutdown_onchannelcallback(void *context) struct icmsg_hdr *icmsghdrp; - vmbus_recvpacket(channel, shut_txf_buf, - HV_HYP_PAGE_SIZE, &recvlen, &requestid); + if (vmbus_recvpacket(channel, shut_txf_buf, HV_HYP_PAGE_SIZE, &recvlen, &requestid)) { + pr_err_ratelimited("Shutdown request received. Could not read into shut txf buf\n"); + return; + } - if (recvlen > 0) { - icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[ - sizeof(struct vmbuspipe_hdr)]; + if (!recvlen) + return; - if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { - if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf, - fw_versions, FW_VER_COUNT, - sd_versions, SD_VER_COUNT, - NULL, &sd_srv_version)) { - pr_info("Shutdown IC version %d.%d\n", - sd_srv_version >> 16, - sd_srv_version & 0xFFFF); - } - } else { - shutdown_msg = - (struct shutdown_msg_data *)&shut_txf_buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("Shutdown request received. Packet length too small: %d\n", + recvlen); + return; + } - /* - * shutdown_msg->flags can be 0(shut down), 2(reboot), - * or 4(hibernate). It may bitwise-OR 1, which means - * performing the request by force. Linux always tries - * to perform the request by force. - */ - switch (shutdown_msg->flags) { - case 0: - case 1: - icmsghdrp->status = HV_S_OK; - work = &shutdown_work; - pr_info("Shutdown request received -" - " graceful shutdown initiated\n"); - break; - case 2: - case 3: - icmsghdrp->status = HV_S_OK; - work = &restart_work; - pr_info("Restart request received -" - " graceful restart initiated\n"); - break; - case 4: - case 5: - pr_info("Hibernation request received\n"); - icmsghdrp->status = hibernation_supported ? - HV_S_OK : HV_E_FAIL; - if (hibernation_supported) - work = &hibernate_context.work; - break; - default: - icmsghdrp->status = HV_E_FAIL; - pr_info("Shutdown request received -" - " Invalid request\n"); - break; - } + icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[sizeof(struct vmbuspipe_hdr)]; + + if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { + if (vmbus_prep_negotiate_resp(icmsghdrp, + shut_txf_buf, recvlen, + fw_versions, FW_VER_COUNT, + sd_versions, SD_VER_COUNT, + NULL, &sd_srv_version)) { + pr_info("Shutdown IC version %d.%d\n", + sd_srv_version >> 16, + sd_srv_version & 0xFFFF); + } + } else if (icmsghdrp->icmsgtype == ICMSGTYPE_SHUTDOWN) { + /* Ensure recvlen is big enough to contain shutdown_msg_data struct */ + if (recvlen < ICMSG_HDR + sizeof(struct shutdown_msg_data)) { + pr_err_ratelimited("Invalid shutdown msg data. Packet length too small: %u\n", + recvlen); + return; } - icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION - | ICMSGHDRFLAG_RESPONSE; - - vmbus_sendpacket(channel, shut_txf_buf, - recvlen, requestid, - VM_PKT_DATA_INBAND, 0); + shutdown_msg = (struct shutdown_msg_data *)&shut_txf_buf[ICMSG_HDR]; + + /* + * shutdown_msg->flags can be 0(shut down), 2(reboot), + * or 4(hibernate). It may bitwise-OR 1, which means + * performing the request by force. Linux always tries + * to perform the request by force. + */ + switch (shutdown_msg->flags) { + case 0: + case 1: + icmsghdrp->status = HV_S_OK; + work = &shutdown_work; + pr_info("Shutdown request received - graceful shutdown initiated\n"); + break; + case 2: + case 3: + icmsghdrp->status = HV_S_OK; + work = &restart_work; + pr_info("Restart request received - graceful restart initiated\n"); + break; + case 4: + case 5: + pr_info("Hibernation request received\n"); + icmsghdrp->status = hibernation_supported ? + HV_S_OK : HV_E_FAIL; + if (hibernation_supported) + work = &hibernate_context.work; + break; + default: + icmsghdrp->status = HV_E_FAIL; + pr_info("Shutdown request received - Invalid request\n"); + break; + } + } else { + icmsghdrp->status = HV_E_FAIL; + pr_err_ratelimited("Shutdown request received. Invalid msg type: %d\n", + icmsghdrp->icmsgtype); } + icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION + | ICMSGHDRFLAG_RESPONSE; + + vmbus_sendpacket(channel, shut_txf_buf, + recvlen, requestid, + VM_PKT_DATA_INBAND, 0); + if (work) schedule_work(work); } @@ -396,19 +411,27 @@ static void timesync_onchannelcallback(void *context) HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (ret) { - pr_warn_once("TimeSync IC pkt recv failed (Err: %d)\n", - ret); + pr_err_ratelimited("TimeSync IC pkt recv failed (Err: %d)\n", + ret); break; } if (!recvlen) break; + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("Timesync request received. Packet length too small: %d\n", + recvlen); + break; + } + icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[ sizeof(struct vmbuspipe_hdr)]; if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { - if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf, + if (vmbus_prep_negotiate_resp(icmsghdrp, + time_txf_buf, recvlen, fw_versions, FW_VER_COUNT, ts_versions, TS_VER_COUNT, NULL, &ts_srv_version)) { @@ -416,33 +439,44 @@ static void timesync_onchannelcallback(void *context) ts_srv_version >> 16, ts_srv_version & 0xFFFF); } - } else { + } else if (icmsghdrp->icmsgtype == ICMSGTYPE_TIMESYNC) { if (ts_srv_version > TS_VERSION_3) { - refdata = (struct ictimesync_ref_data *) - &time_txf_buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + /* Ensure recvlen is big enough to read ictimesync_ref_data */ + if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_ref_data)) { + pr_err_ratelimited("Invalid ictimesync ref data. Length too small: %u\n", + recvlen); + break; + } + refdata = (struct ictimesync_ref_data *)&time_txf_buf[ICMSG_HDR]; adj_guesttime(refdata->parenttime, refdata->vmreferencetime, refdata->flags); } else { - timedatap = (struct ictimesync_data *) - &time_txf_buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + /* Ensure recvlen is big enough to read ictimesync_data */ + if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_data)) { + pr_err_ratelimited("Invalid ictimesync data. Length too small: %u\n", + recvlen); + break; + } + timedatap = (struct ictimesync_data *)&time_txf_buf[ICMSG_HDR]; + adj_guesttime(timedatap->parenttime, hv_read_reference_counter(), timedatap->flags); } + } else { + icmsghdrp->status = HV_E_FAIL; + pr_err_ratelimited("Timesync request received. Invalid msg type: %d\n", + icmsghdrp->icmsgtype); } icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE; vmbus_sendpacket(channel, time_txf_buf, - recvlen, requestid, - VM_PKT_DATA_INBAND, 0); + recvlen, requestid, + VM_PKT_DATA_INBAND, 0); } } @@ -462,18 +496,28 @@ static void heartbeat_onchannelcallback(void *context) while (1) { - vmbus_recvpacket(channel, hbeat_txf_buf, - HV_HYP_PAGE_SIZE, &recvlen, &requestid); + if (vmbus_recvpacket(channel, hbeat_txf_buf, HV_HYP_PAGE_SIZE, + &recvlen, &requestid)) { + pr_err_ratelimited("Heartbeat request received. Could not read into hbeat txf buf\n"); + return; + } if (!recvlen) break; + /* Ensure recvlen is big enough to read header data */ + if (recvlen < ICMSG_HDR) { + pr_err_ratelimited("Hearbeat request received. Packet length too small: %d\n", + recvlen); + break; + } + icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[ sizeof(struct vmbuspipe_hdr)]; if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { if (vmbus_prep_negotiate_resp(icmsghdrp, - hbeat_txf_buf, + hbeat_txf_buf, recvlen, fw_versions, FW_VER_COUNT, hb_versions, HB_VER_COUNT, NULL, &hb_srv_version)) { @@ -482,21 +526,31 @@ static void heartbeat_onchannelcallback(void *context) hb_srv_version >> 16, hb_srv_version & 0xFFFF); } - } else { - heartbeat_msg = - (struct heartbeat_msg_data *)&hbeat_txf_buf[ - sizeof(struct vmbuspipe_hdr) + - sizeof(struct icmsg_hdr)]; + } else if (icmsghdrp->icmsgtype == ICMSGTYPE_HEARTBEAT) { + /* + * Ensure recvlen is big enough to read seq_num. Reserved area is not + * included in the check as the host may not fill it up entirely + */ + if (recvlen < ICMSG_HDR + sizeof(u64)) { + pr_err_ratelimited("Invalid heartbeat msg data. Length too small: %u\n", + recvlen); + break; + } + heartbeat_msg = (struct heartbeat_msg_data *)&hbeat_txf_buf[ICMSG_HDR]; heartbeat_msg->seq_num += 1; + } else { + icmsghdrp->status = HV_E_FAIL; + pr_err_ratelimited("Heartbeat request received. Invalid msg type: %d\n", + icmsghdrp->icmsgtype); } icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE; vmbus_sendpacket(channel, hbeat_txf_buf, - recvlen, requestid, - VM_PKT_DATA_INBAND, 0); + recvlen, requestid, + VM_PKT_DATA_INBAND, 0); } } |