fel: sid: fix stack overflow while reading from SID #201
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When reading from the SID device using the normal memory access method, we upload our "readl" routine (via fel_readl_n()), which expects a number of *words* to read. However length is given in *bytes*, so we read four times as much, and overflow our key buffer, clobbering the return address. This is typically fatal: =============== $ ./sunxi-fel sid 02c05200:12345678:34567890:76543210 Segmentation fault (core dumped) $ =============== Fix this by giving the number of (32-bit) words instead. We already checked that length is a multiple of 4, so we can just divide. Signed-off-by: Andre Przywara <[email protected]>
paulkocialkowski
approved these changes
Nov 3, 2023
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When reading from the SID device using the normal memory access method, we upload our "readl" routine (via fel_readl_n()), which expects a number of words to read. However length is given in bytes, so we read four times as much, and overflow our key buffer, clobbering the return address. This is typically fatal:
Fix this by giving the number of (32-bit) words instead. We already checked that length is a multiple of 4, so we can just divide.