2019-11-08 20:09:16

by Daniel Walker (danielwa)

[permalink] [raw]
Subject: [PATCH 2/2] lib/xz: Fix XZ_DYNALLOC to avoid useless memory reallocations.

From: Lasse Collin <[email protected]>

s->dict.allocated was initialized to 0 but never set after
a successful allocation, thus the code always thought that
the dictionary buffer has to be reallocated.

For the original commit to xz-embedded.git, please refer to:
https://git.tukaani.org/?p=xz-embedded.git;a=commit;h=40d291b

Signed-off-by: Yu Sun <[email protected]>
Cc: [email protected]
Signed-off-by: Daniel Walker <[email protected]>
---
lib/xz/xz_dec_lzma2.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/lib/xz/xz_dec_lzma2.c b/lib/xz/xz_dec_lzma2.c
index 08c3c8049998..156f26fdc4c9 100644
--- a/lib/xz/xz_dec_lzma2.c
+++ b/lib/xz/xz_dec_lzma2.c
@@ -1146,6 +1146,7 @@ XZ_EXTERN enum xz_ret xz_dec_lzma2_reset(struct xz_dec_lzma2 *s, uint8_t props)

if (DEC_IS_DYNALLOC(s->dict.mode)) {
if (s->dict.allocated < s->dict.size) {
+ s->dict.allocated = s->dict.size;
vfree(s->dict.buf);
s->dict.buf = vmalloc(s->dict.size);
if (s->dict.buf == NULL) {
--
2.17.1


2019-11-08 20:29:33

by Daniel Walker (danielwa)

[permalink] [raw]
Subject: Re: [PATCH 2/2] lib/xz: Fix XZ_DYNALLOC to avoid useless memory reallocations.

On Fri, Nov 08, 2019 at 12:00:40PM -0800, Daniel Walker wrote:
> From: Lasse Collin <[email protected]>
>
> s->dict.allocated was initialized to 0 but never set after
> a successful allocation, thus the code always thought that
> the dictionary buffer has to be reallocated.
>
> For the original commit to xz-embedded.git, please refer to:
> https://git.tukaani.org/?p=xz-embedded.git;a=commit;h=40d291b
>
> Signed-off-by: Yu Sun <[email protected]>


Yu made me aware that Lasse had sent this on Nov. 4. I would recommend you
take that patch, and disregard this one. Cisco is using it and we would like
to see it merged.

Daniel

2019-11-08 20:51:51

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH 2/2] lib/xz: Fix XZ_DYNALLOC to avoid useless memory reallocations.

On Fri, 8 Nov 2019 12:27:54 -0800 Daniel Walker <[email protected]> wrote:

> On Fri, Nov 08, 2019 at 12:00:40PM -0800, Daniel Walker wrote:
> > From: Lasse Collin <[email protected]>
> >
> > s->dict.allocated was initialized to 0 but never set after
> > a successful allocation, thus the code always thought that
> > the dictionary buffer has to be reallocated.
> >
> > For the original commit to xz-embedded.git, please refer to:
> > https://git.tukaani.org/?p=xz-embedded.git;a=commit;h=40d291b
> >
> > Signed-off-by: Yu Sun <[email protected]>
>
>
> Yu made me aware that Lasse had sent this on Nov. 4. I would recommend you
> take that patch, and disregard this one. Cisco is using it and we would like
> to see it merged.

No probs. I'll take that as an acked-by ;)