Re: A bug in message_add_payload()

On Tue, 15 Apr 2003, Aref Taidi wrote:

> Dear Sir/Madam,

I'm sorry, but I do not see how that realloc call is bad. It will add space for a new "struct iovec" to msg->iov, and this new space is filled in (both variables) a few lines further down. Clearing that space before this would be pointless. I see no error here.

In fact, the calloc() call for msg->iov in message_alloc() could be replaced with a malloc() call instead, as the same thing happens there.

However, what looks a bit strange in the message_add_payload() function is the allocation of the 'payload_node' struct, as this allocated space is not zeroed, only partially filled in, and used later on during execution. I guess this may be your problem, although I have not checked if those other variables in 'payload_node' are actually used later.

Here's a diff for it:

Index: message.c

diff -u -r1.57 message.c
--- message.c   11 Sep 2002 09:50:44 -0000      1.57
+++ message.c   15 Apr 2003 19:59:31 -0000

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   struct iovec *new_iov;
   struct payload *payload_node;

• payload_node = malloc (sizeof *payload_node); + payload_node = calloc (1, sizeof *payload_node); if (!payload_node) {
• log_error ("message_add_payload: malloc (%lu) failed", + log_error ("message_add_payload: calloc (1, %lu) failed", (unsigned long)sizeof *payload_node); return -1; }

In case I missed anything regarding the realloc() code, please tell me so. If you like, also mail me a diff with a proposed solution for it.

/H

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Håkan Olsson         (+46) 708 437 337     Carlstedt Research
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