Fix overflows with malformed lesskey lines#234
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If lines are malformed it is possible to trigger out of boundary read accesses during parsing. Carefully handle the pointer increments to not move behind the terminating nul byte. How to reproduce: python -c 'print(1022*" "+"\\")' > lesskey-1.txt python -c 'print(1022*" "+"^")' > lesskey-2.txt python -c 'print(1021*" "+"\\k")' > lesskey-3.txt Open these files with lesskey, compiled with -fsanitize=address.
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I did not fuzz possible lesskey files so I do not know if this covers all cases. The last adjustment is probably not necessary -- but I added it just in case. For style reasons it might make sense to modify all *pp = p+1 lines in that function. |
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If lines are malformed it is possible to trigger out of boundary
read accesses during parsing.
Carefully handle the pointer increments to not move behind the
terminating nul byte.
How to reproduce:
python -c 'print(1022*" "+"\")' > lesskey-1.txt
python -c 'print(1022*" "+"^")' > lesskey-2.txt
python -c 'print(1021*" "+"\k")' > lesskey-3.txt
Open these files with lesskey, compiled with -fsanitize=address.