yes

----- Original Message -----
From: "Rakesh.R" <[EMAIL PROTECTED]>
Date: Monday, April 23, 2001 4:27 am
Subject: RE: bug in EVP_MD_CTX_copy()     

> Bharath are u from Chennai?
> 
> -----Original Message-----
> From: T Bharath [mailto:[EMAIL PROTECTED]]
> Sent: Monday, April 23, 2001 1:34 PM
> To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
> Subject: bug in EVP_MD_CTX_copy() 
> 
> Iam trying to use openssl in my app and boundschecker was giving the
> following error
>        stack memory overrun
>        Copying 96 bytes to ctx.digest
>        Starting offset 0,destination size:4 bytes
> The callstack details are
> 
> EVP_MD_CTX_copy()     \crypto\evp\digest.c       line no 90
> ssl3_handshake_mac()   \ssl\s3_enc.c             434
> ssl3_final_finish_mac()  \ssl\s3_enc.c           419
> ssl3_send_finished()     \ssl\s3_both.c         155
> ssl3_connect()          \ssl\s3_clnt.c          329
> SSL_connect()           \ssl\ssl_lib.c          727
> ssl23_get_server_hello() \ssl\s23_clnt.c        469
> ssl23_connect()          \ssl\ssl_clnt.c        179
> SSL_connect()            \ssl\ssl_lib.c         727
> 
> Taking a closer look i found that in
> ssl3_handshake_mac() we have instantiated  EVP_MD_CTX ctx;
> and then call EVP_MD_CTX_copy(&ctx,in_ctx) inside which we do a memcpy
> Now ctx has a pointer member    const EVP_MD *digest;
> When we instantiate ctx ,digest being a member pointer does not get
> allocated any memory and when we do the memcpy inside EVP_MD_CTX_copy
> we are copying data into a dangling pointer.Shouldnt we allocate 
> memoryto ctx.digest before calling EVP_MD_CTX_copy.
> Iam using openssl-0.9.5a but i checked the latest openssl-0.9.6
> engine.This bug is still there
> 
> 
> 
> 
> 
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