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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal">I need one clarification on routine SSL_CTX_free(). I see the memory is not freed even after calling this SSL_CTX_free().<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a simple test program, which just does SSL_CTX_new() and SSL_CTX_free().<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">#include<stdio.h><o:p></o:p></p>
<p class="MsoNormal">#include <openssl/ssl.h><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">int main()<o:p></o:p></p>
<p class="MsoNormal">{<o:p></o:p></p>
<p class="MsoNormal"> const SSL_METHOD *method;<o:p></o:p></p>
<p class="MsoNormal"> SSL_CTX *ctx = NULL;<o:p></o:p></p>
<p class="MsoNormal"> OPENSSL_init_ssl(0, NULL);<o:p></o:p></p>
<p class="MsoNormal"> method = TLS_method();<o:p></o:p></p>
<p class="MsoNormal"> ctx = SSL_CTX_new(method);<o:p></o:p></p>
<p class="MsoNormal"> if ( ctx == NULL ) {<o:p></o:p></p>
<p class="MsoNormal"> return(-1);<o:p></o:p></p>
<p class="MsoNormal"> }<o:p></o:p></p>
<p class="MsoNormal"> SSL_CTX_free(ctx);<o:p></o:p></p>
<p class="MsoNormal"> ctx=NULL;<o:p></o:p></p>
<p class="MsoNormal"> sleep(300);<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If the program is terminated after it enters the sleep, I am seeing memory is still reachable in valgrind.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Here is output from valgrind,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">==443000== 10,224 bytes in 426 blocks are still reachable in loss record 593 of 594<o:p></o:p></p>
<p class="MsoNormal">==443000== at 0x4C34F0B: malloc (vg_replace_malloc.c:307)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x525D775: OPENSSL_LH_insert (in /usr/lib64/libcrypto.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x522DDB2: ??? (in /usr/lib64/libcrypto.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x522E1CF: ERR_load_strings_const (in /usr/lib64/libcrypto.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x4E79083: ERR_load_SSL_strings (in /usr/lib64/libssl.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x4E790BC: ??? (in /usr/lib64/libssl.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x5DABCD6: __pthread_once_slow (in /usr/lib64/libpthread-2.28.so)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x52C4ADC: CRYPTO_THREAD_run_once (in /usr/lib64/libcrypto.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x4E794FA: OPENSSL_init_ssl (in /usr/lib64/libssl.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x4E7D371: SSL_CTX_new (in /usr/lib64/libssl.so.1.1.1g)<o:p></o:p></p>
<p class="MsoNormal">==443000== by 0x400749: main (in /home/hari/a.out)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">SSL_CTX_free is already called before sleep(), but memory is still hanging around.<o:p></o:p></p>
<p class="MsoNormal">Is there something I am missing here? Do I need to follow some other steps ?<o:p></o:p></p>
<p class="MsoNormal">This memory leak is impacting our long term running processes, which allocate and free context.<o:p></o:p></p>
<p class="MsoNormal">Any pointers will be very helpful.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Hari.<o:p></o:p></p>
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