inflate.c: fix potential overflow in inflatePrime #1051
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The condition `state->bits + (uInt)bits > 32` was replaced with `state->bits + (uInt)bits >= 32` to prevent potential overflow when shifting `value` by `state->bits`. A shift equal to or greater than the size of the data type (32 bits) can lead to undefined behavior. This change ensures that the sum of `state->bits` and `bits` never reaches 32, avoiding the risk of overflow in the expression `(unsigned)value << state->bits`. While the scenario leading to overflow is unlikely in practice due to the constraints of the calling function `inflatePrime`, I recommend applying this change to improve code robustness and adhere to safe coding practices. This is a preventive measure to eliminate any potential risks in edge cases. Triggers found by static analyzer Svace. Signed-off-by: Anton Moryakov <[email protected]>
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The condition
state->bits + (uInt)bits > 32was replaced withstate->bits + (uInt)bits >= 32to prevent potential overflow when shiftingvaluebystate->bits. A shift equal to or greater than the size of the data type (32 bits) can lead to undefined behavior.This change ensures that the sum of
state->bitsandbitsnever reaches 32, avoiding the risk of overflow in the expression(unsigned)value << state->bits.While the scenario leading to overflow is unlikely in practice due to the constraints of the calling function
inflatePrime, I recommend applying this change to improve code robustness and adhere to safe coding practices. This is a preventive measure to eliminate any potential risks in edge cases.Triggers found by static analyzer Svace.
Signed-off-by: Anton Moryakov [email protected]