6211 fix jailbreak heap overhang #1043
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nickdowell
approved these changes
Mar 17, 2021
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Goal
Blindly using memcmp to compare env variables to
DYLD_INSERT_LIBRARIESwas breaking when the address sanitizer was on because technically the comparison would run off the end of the array. This is technically not a problem since the ENV vars are all contiguous in memory and the small overhang can't cause real problems, but the address sanitizer IS correctly detecting the undefined behaviour.Changeset
Check if the env var is smaller than
DYLD_INSERT_LIBRARIESand short-circuit if so.Testing
Manually ran the example app before to verify the problem, and afterwards to verify the fix.