Pick patch according to [2]

[1] https://nvd.nist.gov/vuln/detail/CVE-2026-56001
[2] https://security-tracker.debian.org/tracker/CVE-2026-56001

Signed-off-by: Vijay Anusuri <[email protected]>
---
 .../xorg-lib/libxfont/CVE-2026-56001.patch    | 84 +++++++++++++++++++
 .../xorg-lib/libxfont_1.5.4.bb                |  3 +
 2 files changed, 87 insertions(+)
 create mode 100644 meta/recipes-graphics/xorg-lib/libxfont/CVE-2026-56001.patch

diff --git a/meta/recipes-graphics/xorg-lib/libxfont/CVE-2026-56001.patch 
b/meta/recipes-graphics/xorg-lib/libxfont/CVE-2026-56001.patch
new file mode 100644
index 0000000000..506a2dc22a
--- /dev/null
+++ b/meta/recipes-graphics/xorg-lib/libxfont/CVE-2026-56001.patch
@@ -0,0 +1,84 @@
+From be0b08e2d354138d3222b4490e2a77c6ee42f778 Mon Sep 17 00:00:00 2001
+From: Peter Hutterer <[email protected]>
+Date: Mon, 1 Jun 2026 16:46:10 +1000
+Subject: [PATCH] bitscale: fix integer overflow in BitmapScaleBitmaps
+ bytestoalloc
+
+bytestoalloc is declared as unsigned int (32-bit). When the sum of
+per-glyph byte counts exceeds 2^32, the value wraps around and calloc()
+allocates a buffer that is too small. The subsequent ScaleBitmap loop
+then writes past the end of the allocated buffer.
+
+Change bytestoalloc from unsigned int to size_t to match the actual
+allocation size type, and add an explicit overflow check in the
+accumulation loop to bail out if the total would exceed SIZE_MAX.
+
+This vulnerability was discovered by:
+Anonymous working with TrendAI Zero Day Initiative
+
+CVE-2026-56001/ZDI-CAN-30558
+
+Assisted-by: Claude:claude-opus-4-6
+Signed-off-by: Peter Hutterer <[email protected]>
+Part-of: <https://gitlab.freedesktop.org/xorg/lib/libxfont/-/merge_requests/34>
+
+Upstream-Status: Backport [import from debian libxfont1 1.5.2-4+deb9u1
+Upstream commit 
https://gitlab.freedesktop.org/xorg/lib/libxfont/-/commit/be0b08e2d354138d3222b4490e2a77c6ee42f778]
+CVE: CVE-2026-56001
+Signed-off-by: Vijay Anusuri <[email protected]>
+---
+ src/bitmap/bitscale.c | 24 +++++++++++++++++++++---
+ 1 file changed, 21 insertions(+), 3 deletions(-)
+
+diff --git a/src/bitmap/bitscale.c b/src/bitmap/bitscale.c
+index 13ed924..c87fa96 100644
+--- a/src/bitmap/bitscale.c
++++ b/src/bitmap/bitscale.c
+@@ -38,6 +38,7 @@ from The Open Group.
+ #include <X11/fonts/bitmap.h>
+ #include <X11/fonts/fontutil.h>
+ #include <math.h>
++#include <stdint.h>
+ 
+ #ifndef MAX
+ #define   MAX(a,b)    (((a)>(b)) ? a : b)
+@@ -1459,7 +1460,7 @@ BitmapScaleBitmaps(FontPtr pf,          /* scaled font */
+               opci;
+     FontInfoPtr pfi;
+     int         glyph;
+-    unsigned    bytestoalloc = 0;
++    size_t      bytestoalloc = 0;
+     int               firstCol, lastCol, firstRow, lastRow;
+ 
+     double    xform[4], inv_xform[4];
+@@ -1486,8 +1487,25 @@ BitmapScaleBitmaps(FontPtr pf,          /* scaled font 
*/
+     glyph = pf->glyph;
+     for (i = 0; i < nchars; i++)
+     {
+-      if ((pci = ACCESSENCODING(bitmapFont->encoding, i)))
+-          bytestoalloc += BYTES_FOR_GLYPH(pci, glyph);
++      if ((pci = ACCESSENCODING(bitmapFont->encoding, i))) {
++          size_t glyphsize = BYTES_FOR_GLYPH(pci, glyph);
++          if (bytestoalloc > SIZE_MAX - glyphsize) {
++              fprintf(stderr,
++                      "Error: bitmap allocation overflow for scaled font\n");
++              goto bail;
++          }
++          bytestoalloc += glyphsize;
++      }
++    }
++
++    /* Reject unreasonably large bitmap allocations that could result
++     * from malicious fonts with extreme scale factors.  256 MiB is
++     * far beyond any legitimate scaled bitmap font. */
++#define BITMAP_SCALE_MAX_ALLOC        (256 * 1024 * 1024)
++    if (bytestoalloc > BITMAP_SCALE_MAX_ALLOC) {
++      fprintf(stderr,
++             "Error: scaled bitmap size %zu exceeds limit\n", bytestoalloc);
++       goto bail;
+     }
+ 
+     /* Do we add the font malloc stuff for VALUE ADDED ? */
+-- 
+2.43.0
+
diff --git a/meta/recipes-graphics/xorg-lib/libxfont_1.5.4.bb 
b/meta/recipes-graphics/xorg-lib/libxfont_1.5.4.bb
index 9ec7cc30f5..59c489b785 100644
--- a/meta/recipes-graphics/xorg-lib/libxfont_1.5.4.bb
+++ b/meta/recipes-graphics/xorg-lib/libxfont_1.5.4.bb
@@ -19,6 +19,9 @@ XORG_EXT = "tar.bz2"
 
 BBCLASSEXTEND = "native"
 
+SRC_URI += "file://CVE-2026-56001.patch \
+           "
+
 SRC_URI[sha256sum] = 
"1a7f7490774c87f2052d146d1e0e64518d32e6848184a18654e8d0bb57883242"
 
 PACKAGECONFIG ??= "${@bb.utils.filter('DISTRO_FEATURES', 'ipv6', d)}"
-- 
2.43.0

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