CoAP blockwise code is out of spec and causes hard fault

[Alex-EEE]

Description of defect

In the line of code below, you are calculating the offset using the max block size of the MBED DEVICE, which is WRONG and out of spec (https://tools.ietf.org/html/rfc7959#page-29)

You need to calculate the offset using THE BLOCK SIZE SENT IN THE PACKET.

mbed-os/connectivity/libraries/mbed-coap/source/sn_coap_protocol.c

Line 1283 in 0548981

memcpy(stored_blockwise_payload_ptr->payload_ptr + (block_number * handle->sn_coap_block_data_size), payload_ptr, payload_len);

block_number * handle->sn_coap_block_data_size is wrong. handle->sn_coap_block_data_size is the max blockwise size of the device, NOT the block size of the packet you're currently processing

You need to pass the block_size into this function as contained in the incoming back. (You derive this value already on line 1925 of the same file) ( uint16_t block_size = 1u << (block_temp + 4);)

Target(s) affected by this defect ?

All targets

Toolchain(s) (name and version) displaying this defect ?

All toolchains, but I'm using IAR

What version of Mbed-os are you using (tag or sha) ?

master (0548981)
#0548981

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

How is this defect reproduced ?

Send a blockwise PUT using a smaller blockwise size than is set in SN_COAP_MAX_BLOCKWISE_PAYLOAD_SIZE

[ciarmcom]

@Alex-EEE thank you for raising this issue.Please take a look at the following comments:

We cannot automatically identify a release based on the version of Mbed OS that you have provided.
Please provide either a single valid sha of the form #abcde12 or #3b8265d70af32261311a06e423ca33434d8d80de
or a single valid release tag of the form mbed-os-x.y.z .
E.g. '(0548981)' has not been matched as a valid tag or sha.It would help if you could also specify the versions of any tools you are using?

NOTE: If there are fields which are not applicable then please just add 'n/a' or 'None'.This indicates to us that at least all the fields have been considered.
Please update the issue header with the missing information, the issue will not be mirroredto our internal defect tracking system or investigated until this has been fully resolved.

[0xc0170]

@teetak01 would you be able to review if this fix should be upstreamed?

[teetak01]

Thanks @Alex-EEE

Looks like a valid issue.

Internal ticket https://armiot.atlassian.net/browse/IOTCLT-4475

[ciarmcom]

@Alex-EEE it has been 5 days since the last reminder. Could you please update the issue header as previously requested?

[ristohuhtala]

@Alex-EEE PR to fix this into mbed-os is #13787

[ciarmcom]

@Alex-EEE it has been 5 days since the last reminder. Could you please update the issue header as previously requested?

[ciarmcom]

@Alex-EEE it has been 5 days since the last reminder. Could you please update the issue header as previously requested?

[ciarmcom]

@Alex-EEE it has been 5 days since the last reminder. Could you please update the issue header as previously requested?

[ciarmcom]

@Alex-EEE it has been 5 days since the last reminder. Could you please update the issue header as previously requested?

[0xc0170]

Updated via referenced PRs, I'll close as resolved.