[pacman-dev] [PATCH] Reset dload_interrupted early in curl_download_internal()

[Dan McGee]

On Thu, Aug 18, 2011 at 2:13 AM, Lukas Fleischer
<archlinux at cryptocrack.de> wrote:
> On Wed, Aug 17, 2011 at 04:54:56PM +0200, Lukas Fleischer wrote:
>> Avoid invoking unlink() with a NULL path if the URL isn't to a file and
>> we fail to create a temporary file.
>>
>> Signed-off-by: Lukas Fleischer <archlinux at cryptocrack.de>
>> ---
>>  lib/libalpm/dload.c |    4 +++-
>>  1 files changed, 3 insertions(+), 1 deletions(-)
>>
>
> Note that this still isn't fixed with the latest refactoring (not sure
> if 9f139550 was supposed to fix this). If we fail to create a temporary
> file (around line 224), tempfile still points to NULL and the unlink()
> invocation might result in a segfault.
Can you outline *exactly* what needs to happen for this case to take
place? I'm not seeing it, or at least I don't think your case is when
it would happen. If the STRDUP() into tempfile fails, we return -1 on
the spot and don't continue any further.

If on the other hand, ret stays at its default -1,
payload->allow_resume is 0 (making should_unlink 1), and we goto
cleanup before tempfile has been allocated, this could be a problem.
Hoewver, I see no code path where this is possible.

-Dan