We must not draw anti-aliased lines on palette images, because that is
not supported by `gdImageSetAAPixelColor()` and it wouldn't make much
sense to support it, due to the limitation to at most 256 colors.
Besides that we still hope to sync the complete bundled libgd sometime,
the upstream implementation of `gdImageCrop()` is much simpler than the
current one, and thus better readable and less error prone.
* 'master' of git.php.net:/php-src:
Update NEWS
Fixed bug #75571: Potential infinite loop in gdImageCreateFromGifCtx
Fix bug #74782: remove file name from output to avoid XSS
* 'PHP-7.2' of git.php.net:/php-src:
Update NEWS
Fixed bug #75571: Potential infinite loop in gdImageCreateFromGifCtx
Fix bug #74782: remove file name from output to avoid XSS
* 'PHP-7.1' of git.php.net:/php-src:
Update NEWS
Fixed bug #75571: Potential infinite loop in gdImageCreateFromGifCtx
Fix bug #74782: remove file name from output to avoid XSS
Due to a signedness confusion in `GetCode_` a corrupt GIF file can
trigger an infinite loop. Furthermore we make sure that a GIF without
any palette entries is treated as invalid *after* open palette entries
have been removed.
We apply the respective patches from external libgd, work around the
still missing `gdImageClone()`, and fix the special cased rotation
routines according to Pierre's patch
(https://gist.github.com/pierrejoye/59d72385ed1888cf8894a7ed437235ae).
We also cater to bug73272.phpt whose result obviously changes a bit.
We back-port dd48286 even though
we cannot come up with a regression test, because the erroneous
condition appears to be impossible to trigger.
We also parenthesize the inner ternary operation to avoid confusion.
We have to make sure to avoid alpha-blending issues by explicitly
switching to `gdEffectReplace` and to restore the old value afterwards.
This is a port of <a7a7ece>.
Crafted BMP images can cause dynamicSeek() to be called with a negative
position which must not be allowed, since dynamicSeek() works like
fseek() in SEEK_SET mode. We solve this by bailing out if `pos` is
negative, and let the image reading fail gracefully.
We must take into account the line padding, when we're reading XBM
files.
We deliberately ignore the potential integer overflow here, because
that would be caught by gdImageCreate() or even earlier if `bytes==0`,
what happens in libgd00094.phpt which we adapt accordingly.
GD2 stores the number of horizontal and vertical chunks as words (i.e. 2
byte unsigned). These values are multiplied and assigned to an int when
reading the image, what can cause integer overflows. We have to avoid
that, and also make sure that either chunk count is actually greater
than zero. If illegal chunk counts are detected, we bail out from
reading the image.
(cherry picked from commit 5b5d9db3988b829e0b121b74bb3947f01c2796a1)
We must not pretend that there are image data if there are none. Instead
we fail reading the image file gracefully.
(cherry picked from commit cdb648dc4115ce0722f3cc75e6a65115fc0e56ab)
We add PHP bindings for libgd's features to read and write BMP files, which
are available as of libgd 2.1.0.
As PHP's bundled libgd doesn't yet include the respective features of the
external libgd, we add these.
