fluf: fix UB in get_option_from_buff #75
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Make temp_payload_len local of type uint16_t instead of size_t to pass a ptr to update_extended_option without causing undefined behaviour. Function update_extended_option dereferences passed uint16_t ptr which in this case is pointing to size_t type. When built with Arm GNU Toolchain 13.2.rel1 with flags: ``` -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mthumb -Os -Wall ``` compiled code is incorrect which leads to `opt->payload_len` not being properly updated which subsequently leads to wrong if condition result which causes FLUF_ERR_BUFF error later on.
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Make temp_payload_len local of type uint16_t instead of size_t to pass a ptr to update_extended_option without causing undefined behaviour.
Function update_extended_option dereferences passed uint16_t ptr which in this case is pointing to size_t type.
When built with Arm GNU Toolchain 13.2.rel1 with flags:
compiled code is incorrect which leads to
opt->payload_lennot being properly updated which subsequently leads to wrong if condition result which causes FLUF_ERR_BUFF error later on.Signed-off-by: Piotr Zalewski [email protected]