On Fri, Oct 17, 2014 at 02:33:27PM +0200, Thilo Borgmann wrote:
> Am 16.10.14 04:47, schrieb Michael Niedermayer:
> > On Mon, Oct 13, 2014 at 09:40:42AM +0200, Thilo Borgmann wrote:
> >> Am 11.10.14 16:19, schrieb Nicolas George:
> >>> [...]
> >>
> >> all remarks applied.
> >>
> >> -Thilo
> >>
> >
> >> mov.c | 16 ++++++++++++----
> >> 1 file changed, 12 insertions(+), 4 deletions(-)
> >> cabb6e51de7f9329603561773f209b6a948478ce
> >> 0001-lavf-mov.c-Allocate-buffer-in-case-of-long-metadata-.patch
> >> From 5a14ef97ffc7d82dea5644c736e6dc2de2079e89 Mon Sep 17 00:00:00 2001
> >> From: Thilo Borgmann <thilo.borgm...@mail.de>
> >> Date: Mon, 13 Oct 2014 09:36:17 +0200
> >> Subject: [PATCH] lavf/mov.c: Allocate buffer in case of long metadata
> >> entries.
> >>
> >> ---
> >> libavformat/mov.c | 16 ++++++++++++----
> >> 1 file changed, 12 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/libavformat/mov.c b/libavformat/mov.c
> >> index 4ff46dd..8d6d074 100644
> >> --- a/libavformat/mov.c
> >> +++ b/libavformat/mov.c
> >> @@ -261,7 +261,9 @@ static int mov_read_udta_string(MOVContext *c,
> >> AVIOContext *pb, MOVAtom atom)
> >> #ifdef MOV_EXPORT_ALL_METADATA
> >> char tmp_key[5];
> >> #endif
> >> - char str[1024], key2[16], language[4] = {0};
> >> + char str_small[1024], key2[16], language[4] = {0};
> >> + char *str = str_small;
> >> + char *pstr = NULL;
> >> const char *key = NULL;
> >> uint16_t langcode = 0;
> >> uint32_t data_type = 0, str_size;
> >> @@ -358,13 +360,17 @@ static int mov_read_udta_string(MOVContext *c,
> >> AVIOContext *pb, MOVAtom atom)
> >> if (atom.size < 0)
> >> return AVERROR_INVALIDDATA;
> >>
> >> - str_size = FFMIN3(sizeof(str)-1, str_size, atom.size);
> >> -
> >> if (parse)
> >> parse(c, pb, str_size, key);
> >> else {
> >> + if (str_size > sizeof(str_small)-1) { // allocate buffer for long
> >> data field
> >> + pstr = str = av_malloc(str_size);
> >> + if (!pstr)
> >> + return AVERROR(ENOMEM);
> >> + }
> >> +
> >> if (data_type == 3 || (data_type == 0 && (langcode < 0x400 ||
> >> langcode == 0x7fff))) { // MAC Encoded
> >> - mov_read_mac_string(c, pb, str_size, str, sizeof(str));
> >> + mov_read_mac_string(c, pb, str_size, str, str_size);
> >
> > this seems to store UTF8, which can require more space than str_size
>
> New patch attached using a worst-case size of twice the input string size if
> the input is in utf8.
>
> Tested only with non utf8 by now - I would appreciate it if someone could test
> this with UTF8 metadata or tell me how to generate/where to get a suitable
> file.
>
> -Thilo
>
> mov.c | 27 ++++++++++++++++++++++-----
> 1 file changed, 22 insertions(+), 5 deletions(-)
> c6706cd53f0c804d993ba5dec8112faf1b9e84e5
> 0001-lavf-mov.c-Allocate-buffer-in-case-of-long-metadata-.patch
> From 1a59272e3d333c784e9f4857cd3aa6542ad28d6d Mon Sep 17 00:00:00 2001
> From: Thilo Borgmann <thilo.borgm...@mail.de>
> Date: Fri, 17 Oct 2014 14:30:30 +0200
> Subject: [PATCH] lavf/mov.c: Allocate buffer in case of long metadata entries.
>
> ---
> libavformat/mov.c | 27 ++++++++++++++++++++++-----
> 1 file changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 4ff46dd..a48877d 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -261,7 +261,9 @@ static int mov_read_udta_string(MOVContext *c,
> AVIOContext *pb, MOVAtom atom)
> #ifdef MOV_EXPORT_ALL_METADATA
> char tmp_key[5];
> #endif
> - char str[1024], key2[16], language[4] = {0};
> + char str_small[1024], key2[16], language[4] = {0};
> + char *str = str_small;
> + char *pstr = NULL;
> const char *key = NULL;
> uint16_t langcode = 0;
> uint32_t data_type = 0, str_size;
> @@ -358,15 +360,28 @@ static int mov_read_udta_string(MOVContext *c,
> AVIOContext *pb, MOVAtom atom)
> if (atom.size < 0)
> return AVERROR_INVALIDDATA;
>
> - str_size = FFMIN3(sizeof(str)-1, str_size, atom.size);
> -
> if (parse)
> parse(c, pb, str_size, key);
> else {
> +#define LONG_META_ALLOC() { \
> + if (str_size > sizeof(str_small)-1) { \
> + pstr = str = av_malloc(str_size); \
> + if (!pstr) \
> + return AVERROR(ENOMEM); \
> + } \
> +}
> +
> if (data_type == 3 || (data_type == 0 && (langcode < 0x400 ||
> langcode == 0x7fff))) { // MAC Encoded
> - mov_read_mac_string(c, pb, str_size, str, sizeof(str));
> + int str_size_in = str_size;
> + str_size <<= 1; // worst-case requirement for output string in
> case of utf8 coded input
> + // allocate buffer for long data field if necessary
> + LONG_META_ALLOC();
> + mov_read_mac_string(c, pb, str_size_in, str, str_size);
> } else {
> - int ret = avio_read(pb, str, str_size);
> + int ret;
> + // allocate buffer for long data field if necessary
> + LONG_META_ALLOC();
> + ret = avio_read(pb, str, str_size);
i think it would be simpler to always allocate with no str_small
local buffer case.
Also always allocating 2x the size should avoid the macro
[...]
--
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
You can kill me, but you cannot change the truth.
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