Possible memory leak in auparse_interpret_sock_parts()

Possible memory leak in auparse_interpret_sock_parts()

[Tarun Ramesh]

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Hi,

In the function auparse_interpret_sock_parts() in auparse/auparse.c, for
the line:
const char *val = nvlist_interp_cur_val(r, au->escape_mode);

I see that the function nvlist_interp_cur_val() eventually calls
auparse_do_interpretation() which has the comment "Returns a malloc'ed
buffer that the caller must free"
The call path is:
nvlist_interp_cur_val() -> interpret() -> auparse_do_interpretation()

In auparse_interpret_sock_parts():
const char *val = nvlist_interp_cur_val(r, au->escape_mode);
is called and then the value of 'val' is overwritten by:
val = strstr(tmp, field);

The initial memory pointed to by 'val' is never freed, which might be a
memory leak.
Please let me know if I;m missing something.

Thanks,
Tarun

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Re: Possible memory leak in auparse_interpret_sock_parts()

[Steve Grubb]

On Friday, June 21, 2019 7:34:12 AM EDT Tarun Ramesh wrote:
> Hi,
> 
> In the function auparse_interpret_sock_parts() in auparse/auparse.c, for
> the line:
> const char *val = nvlist_interp_cur_val(r, au->escape_mode);
> 
> I see that the function nvlist_interp_cur_val() eventually calls
> auparse_do_interpretation() which has the comment "Returns a malloc'ed
> buffer that the caller must free"
> The call path is:
> nvlist_interp_cur_val() -> interpret() -> auparse_do_interpretation()
> 
> In auparse_interpret_sock_parts():
> const char *val = nvlist_interp_cur_val(r, au->escape_mode);
> is called and then the value of 'val' is overwritten by:
> val = strstr(tmp, field);
> 
> The initial memory pointed to by 'val' is never freed, which might be a
> memory leak.
> Please let me know if I;m missing something.

nvlist_interp_cur_val() maintains custody of that chunk of memory and frees 
it when the list is cleared. I have a testcase for this and valgrind is 
showing no leaks.

-Steve