19 Feb
2022
19 Feb
'22
8:32 p.m.
Hello,
Please make sure that you're correctly freeing all contexts. In particular, note that each call to malloc() or calloc() must have a corresponding call to free(), AND each call to mbedtls_cipher_init() must have a corresponding call to mbedtls_cipher_free(). Despite the name, mbedtls_xxx_free() functions do not free the memory used by their argument itself (and it can be on the stack or a global variable), they only free resources used by their argument.
If that's not the problem, I recommend doing static analysis or doing stress tests under a memory allocation framework. For Mbed TLS, we do static analysis with Coverity (expensive but nice), and runtime testing with AddressSanitizer and Valgrind.
Best regards,
--
Gilles Peskine
Mbed TLS developer
On 18/02/2022 04:40, Subramanian Gopi Krishnan via mbed-tls wrote:
>
> Hi,
>
>
>
>
>
> I have ported mbedtls library on am embedded platform developed to
> encrypt / decrypt messages using AES GCM 256 key. After several hours
> of running, we are experiencing error MBEDTLS_ERR_CIPHER_ALLOC_FAILED
> 0x6180 and malloc functions fails as the heap seems to be piled-up.
>
>
>
> How could I is using correct free function and the actual allocated
> memory is freed?
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>
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>
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> Thanks,
>
> Gopi Krishnan
>
>