[flashrom-gerrit] Change in flashrom[master]: writeprotect_ranges.c: Check for underflow when using unsigned types

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Attention is currently required from: Angel Pons, Light, Nikolai Artemiev.
Hello build bot (Jenkins), Nico Huber, Nikolai Artemiev,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/flashrom/+/62733

to look at the new patch set (#6).

Change subject: writeprotect_ranges.c: Check for underflow when using unsigned types
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writeprotect_ranges.c: Check for underflow when using unsigned types

size_t is an unsigned type so bp_max-2 causes an underflow. This results
in undefined behaviour. So assert before that bits->bp_bit-count > 1 so
that bp_max has a minimum value of 2. But the when bp_bit_count == 0
then bp == 0 and when bp_bit_count == 1 then bp == 0 or bp == 1 ==
bp_max. These cases are handled seaprately so the underflow will never
occur. Ignore the tool for this issue.

Change-Id: I2766ef8e34f7121dad746e5f32a835d480ae1cad
Signed-off-by: Aarya Chaumal 
---
M writeprotect_ranges.c
1 file changed, 3 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/33/62733/6