Backport 2.16: Guard from undefined behaviour in case of an INT_MAX max_pathlen #3197
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Backport of #3192 |
Patater
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Apr 17, 2020
When parsing a certificate with the basic constraints extension the max_pathlen that was read from it was incremented regardless of its value. However, if the max_pathlen is equal to INT_MAX (which is highly unlikely), an undefined behaviour would occur. This commit adds a check to ensure that such value is not accepted as valid. Relevant tests for INT_MAX and INT_MAX-1 are also introduced. Certificates added in this commit were generated using the test_suite_x509write, function test_x509_crt_check. Input data taken from the "Certificate write check Server1 SHA1" test case, so the generated files are like the "server1.crt", but with the "is_ca" field set to 1 and max_pathlen as described by the file name. Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com> Signed-off-by: Piotr Nowicki <piotr.nowicki@arm.com>
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…low fix Backport of Mbed-TLS#3192 Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
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When parsing a certificate with the basic constraints extension, the max_pathlen that was read from it was incremented regardless of its value. However, if the max_pathlen is equal to INT_MAX (which is highly unlikely), an undefined behaviour would occur. This commit adds a check to ensure that such value is not accepted as valid. Relevant tests for INT_MAX and INT_MAX-1 are also introduced.
Certificates added in this commit were generated using the test_suite_x509write, function test_x509_crt_check. Input data taken from the "Certificate write check Server1 SHA1" test case, so the generated files are like the "server1.crt", but with the "is_ca" field set to 1 and max_pathlen as described by the file name.
This PR addresses IOTSSL-2774.