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From: Paolo Bonzini <pbonzini@redhat.com>
To: Eric Blake <eblake@redhat.com>, qemu-devel@nongnu.org
Cc: armbru@redhat.com
Subject: Re: [Qemu-devel] [PATCH 4/4] qjson: surprise, allocating 6 QObjects per token is expensive
Date: Fri, 20 Nov 2015 21:19:02 +0100	[thread overview]
Message-ID: <564F8036.6010905@redhat.com> (raw)
In-Reply-To: <564F6B17.5040201@redhat.com>



On 20/11/2015 19:48, Eric Blake wrote:
>> > +    token = g_malloc(sizeof(JSONToken) + input->len + 1);
>> > +    token->type = type;
>> > +    memcpy(token->str, input->str, input->len + 1);
>> > +    token->str[input->len] = 0;
> Looks like you are writing the last byte twice.  Either the +1 in the
> memcpy() always copies a NUL byte and we don't need the second
> assignment, or you should drop the +1.
> 
> Otherwise, looks like a sane replacement that saves a lot of memory.

You're right.  The memcpy is wrong and reads out of bounds.

Paolo

> Reviewed-by: Eric Blake <eblake@redhat.com>
> 
> Are we hoping to get this in 2.5 because it fixes the memory hog bug, or
> are we considering that it is not a regression from 2.4 and therefore
> something that should wait for 2.6?

      reply	other threads:[~2015-11-20 20:19 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-20  9:04 [Qemu-devel] [PATCH 0/4] qjson: save a lot of memory Paolo Bonzini
2015-11-20  9:04 ` [Qemu-devel] [PATCH 1/4] qjson: replace QString in JSONLexer with GString Paolo Bonzini
2015-11-20 18:23   ` Eric Blake
2015-11-20 20:16     ` Paolo Bonzini
2015-11-20  9:04 ` [Qemu-devel] [PATCH 2/4] qjson: do not save/restore contexts Paolo Bonzini
2015-11-20 18:28   ` Eric Blake
2015-11-20 20:17     ` Paolo Bonzini
2015-11-20  9:04 ` [Qemu-devel] [PATCH 3/4] qjson: store tokens in a GQueue Paolo Bonzini
2015-11-20 18:40   ` Eric Blake
2015-11-20  9:04 ` [Qemu-devel] [PATCH 4/4] qjson: surprise, allocating 6 QObjects per token is expensive Paolo Bonzini
2015-11-20 18:48   ` Eric Blake
2015-11-20 20:19     ` Paolo Bonzini [this message]

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