tree 2f408e4be825db0811cfbe5602267114f556ed9d
parent b20bbd1ddc2767ce3159d4d0eb3fb82c5dca0c31
author Gilles Peskine <Gilles.Peskine@arm.com> 1611783043 +0100
committer Gilles Peskine <Gilles.Peskine@arm.com> 1612183191 +0100

mbedtls_mpi_sub_abs: fix buffer overflow in error case

Fix a buffer overflow in mbedtls_mpi_sub_abs() when calculating
|A| - |B| where |B| is larger than |A| and has more limbs (so the
function should return MBEDTLS_ERR_MPI_NEGATIVE_VALUE).

Fix #4042

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>