new file mode 100644
@@ -0,0 +1,164 @@
+From cf155de014fc6c5cb199dd681dd5c8fb70429072 Mon Sep 17 00:00:00 2001
+From: Cosmin Truta <ctruta@gmail.com>
+Date: Sat, 10 Jan 2026 15:20:18 +0200
+Subject: [PATCH] fix: Remove incorrect truncation casts from
+ `png_write_image_*`
+
+The type of the row stride (`display->row_bytes`) is ptrdiff_t. Casting
+to png_uint_16 before division will truncate large strides, causing
+incorrect pointer arithmetic for images exceeding 65535 bytes per row.
+For bottom-up images (negative stride), the truncation also corrupts
+the sign, advancing the row pointer forward instead of backward.
+
+Remove the erroneous casts and let the compiler handle the pointer
+arithmetic correctly. Also replace `sizeof (png_uint_16)` with 2.
+
+Add regression test via `pngstest --stride-extra N` where N > 32767
+triggers the affected code paths.
+
+A NOTE ABOUT HISTORY:
+The original code in libpng 1.5.6 (2011) had no such casts. They were
+introduced in libpng 1.6.26 (2016), likely to silence compiler warnings
+on 16-bit systems where the cast would be a no-op. On 32/64-bit systems
+the cast truncates the strides above 65535 and corrupts the negative
+strides.
+
+CVE: CVE-2026-22801
+Upstream-Status: Backport [https://github.com/pnggroup/libpng/commit/cf155de014fc6c5cb199dd681dd5c8fb70429072]
+Signed-off-by: Peter Marko <peter.marko@siemens.com>
+---
+ CMakeLists.txt | 7 +++++++
+ contrib/libtests/pngstest.c | 29 ++++++++++++++++++++++++++++-
+ pngwrite.c | 10 +++++-----
+ tests/pngstest-large-stride | 8 ++++++++
+ 4 files changed, 48 insertions(+), 6 deletions(-)
+ create mode 100755 tests/pngstest-large-stride
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index a8cd82402..a595ed91d 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -804,6 +804,13 @@ if(PNG_TESTS AND PNG_SHARED)
+ endforeach()
+ endforeach()
+
++ # Regression test:
++ # Use stride_extra > 32767 to trigger row_bytes > 65535 for linear images.
++ png_add_test(NAME pngstest-large-stride
++ COMMAND pngstest
++ OPTIONS --stride-extra 33000 --tmpfile "large-stride-" --log
++ FILES "${CMAKE_CURRENT_SOURCE_DIR}/contrib/testpngs/rgb-alpha-16-linear.png")
++
+ add_executable(pngunknown ${pngunknown_sources})
+ target_link_libraries(pngunknown png)
+
+diff --git a/contrib/libtests/pngstest.c b/contrib/libtests/pngstest.c
+index ff4c2b24a..2f29afee2 100644
+--- a/contrib/libtests/pngstest.c
++++ b/contrib/libtests/pngstest.c
+@@ -1,7 +1,7 @@
+
+ /* pngstest.c
+ *
+- * Copyright (c) 2021 Cosmin Truta
++ * Copyright (c) 2021-2026 Cosmin Truta
+ * Copyright (c) 2013-2017 John Cunningham Bowler
+ *
+ * This code is released under the libpng license.
+@@ -3571,6 +3571,33 @@ main(int argc, char **argv)
+ opts |= NO_RESEED;
+ else if (strcmp(arg, "--fault-gbg-warning") == 0)
+ opts |= GBG_ERROR;
++ else if (strcmp(arg, "--stride-extra") == 0)
++ {
++ if (c+1 < argc)
++ {
++ char *ep;
++ unsigned long val = strtoul(argv[++c], &ep, 0);
++
++ if (ep > argv[c] && *ep == 0 && val <= 65535)
++ stride_extra = (int)val;
++
++ else
++ {
++ fflush(stdout);
++ fprintf(stderr, "%s: bad argument for --stride-extra: %s\n",
++ argv[0], argv[c]);
++ exit(99);
++ }
++ }
++
++ else
++ {
++ fflush(stdout);
++ fprintf(stderr, "%s: missing argument for --stride-extra\n",
++ argv[0]);
++ exit(99);
++ }
++ }
+ else if (strcmp(arg, "--tmpfile") == 0)
+ {
+ if (c+1 < argc)
+diff --git a/pngwrite.c b/pngwrite.c
+index 08066bcc4..a95b846c8 100644
+--- a/pngwrite.c
++++ b/pngwrite.c
+@@ -1,7 +1,7 @@
+
+ /* pngwrite.c - general routines to write a PNG file
+ *
+- * Copyright (c) 2018-2022 Cosmin Truta
++ * Copyright (c) 2018-2026 Cosmin Truta
+ * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
+ * Copyright (c) 1996-1997 Andreas Dilger
+ * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
+@@ -1632,7 +1632,7 @@ png_write_image_16bit(png_voidp argument)
+ }
+
+ png_write_row(png_ptr, png_voidcast(png_const_bytep, display->local_row));
+- input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16));
++ input_row += display->row_bytes / 2;
+ }
+
+ return 1;
+@@ -1758,7 +1758,7 @@ png_write_image_8bit(png_voidp argument)
+
+ png_write_row(png_ptr, png_voidcast(png_const_bytep,
+ display->local_row));
+- input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16));
++ input_row += display->row_bytes / 2;
+ } /* while y */
+ }
+
+@@ -1783,7 +1783,7 @@ png_write_image_8bit(png_voidp argument)
+ }
+
+ png_write_row(png_ptr, output_row);
+- input_row += (png_uint_16)display->row_bytes/(sizeof (png_uint_16));
++ input_row += display->row_bytes / 2;
+ }
+ }
+
+@@ -2102,7 +2102,7 @@ png_image_write_main(png_voidp argument)
+ ptrdiff_t row_bytes = display->row_stride;
+
+ if (linear != 0)
+- row_bytes *= (sizeof (png_uint_16));
++ row_bytes *= 2;
+
+ if (row_bytes < 0)
+ row += (image->height-1) * (-row_bytes);
+diff --git a/tests/pngstest-large-stride b/tests/pngstest-large-stride
+new file mode 100755
+index 000000000..7958c5b42
+--- /dev/null
++++ b/tests/pngstest-large-stride
+@@ -0,0 +1,8 @@
++#!/bin/sh
++
++# Regression test:
++# Use stride_extra > 32767 to trigger row_bytes > 65535 for linear images.
++exec ./pngstest \
++ --stride-extra 33000 \
++ --tmpfile "large-stride-" \
++ --log "${srcdir}/contrib/testpngs/rgb-alpha-16-linear.png"
@@ -23,6 +23,7 @@ SRC_URI = "\
file://CVE-2025-66293-01.patch \
file://CVE-2025-66293-02.patch \
file://CVE-2026-22695.patch \
+ file://CVE-2026-22801.patch \
"
SRC_URI[sha256sum] = "1f4696ce70b4ee5f85f1e1623dc1229b210029fa4b7aee573df3e2ba7b036937"