[OE-core][scarthgap][PATCH] vim: Fix CVE-2026-52858 regression

["Devansh Patel -X (devanshp - E INFOCHIPS PRIVATE LIMITED at Cisco)" <devanshp@cisco.com>]

From: Devansh Patel <devanshp@cisco.com>

This patch fixes a regression introduced by the CVE-2026-52858 fix
already carried by OE-Core in commit [1]. The original security fix
added the g:pythoncomplete_allow_import opt-in, but the documented
behavior was broken because vim was not imported in the completion
class scope. This patch applies upstream Vim patch 9.2.0568 to restore
that behavior.

[1] https://github.com/openembedded/openembedded-core/commit/1c08fa48b6765ace24a261ecf43f871e850cee88
[2] https://github.com/vim/vim/commit/4b850457e12e1a678dd209f2868154f7553cbf8d
[3] https://github.com/vim/vim/commit/868ad62cb8bf8038322eab2badd31bd98b02b9df
[4] https://github.com/vim/vim/security/advisories/GHSA-52mc-rq6p-rc7c

Signed-off-by: Devansh Patel <devanshp@cisco.com>
---
 .../vim/files/CVE-2026-52858-regression.patch | 94 +++++++++++++++++++
 meta/recipes-support/vim/vim.inc              |  1 +
 2 files changed, 95 insertions(+)
 create mode 100644 meta/recipes-support/vim/files/CVE-2026-52858-regression.patch

diff --git a/meta/recipes-support/vim/files/CVE-2026-52858-regression.patch b/meta/recipes-support/vim/files/CVE-2026-52858-regression.patch
new file mode 100644
index 0000000000..d3b11a6262
--- /dev/null
+++ b/meta/recipes-support/vim/files/CVE-2026-52858-regression.patch
@@ -0,0 +1,94 @@
+From 8075209bb1e721ca89c2e7fd5d216d7fe2bd3ea6 Mon Sep 17 00:00:00 2001
+From: thinca <thinca@gmail.com>
+Date: Sun, 31 May 2026 12:33:07 +0000
+Subject: [PATCH] patch 9.2.0568: pythoncomplete: g:pythoncomplete_allow_import
+ had no effect
+
+Problem:  The security patch 9.2.0561 added a vim.eval() call inside
+          Completer.evalsource() to honor g:pythoncomplete_allow_import.
+          But the 'vim' module is only imported inside the outer
+          vimcomplete() / vimpy3complete() function, not at the script's
+          top level, so referring to it from a Completer method raises
+          NameError.  The surrounding bare 'except' silently swallows
+          the error and leaves allow_imports at 0, meaning the opt-in
+          never takes effect -- 'import os' (and any other
+          buffer-level import) is always skipped, no candidates are
+          produced for 'os.<...>' and
+          Test_popup_and_preview_autocommand() fails on the Windows
+          CI matrix (Linux skips the test because Python 2 is absent).
+Solution: Re-import 'vim' at the top of evalsource() in both
+          pythoncomplete.vim and python3complete.vim so the eval reads
+          the global, and set g:pythoncomplete_allow_import = 1 in the
+          test (it is the opt-in intended for callers that trust the
+          buffer contents) (thinca).
+
+closes: #20386
+
+CVE: CVE-2026-52858
+Upstream-Status: Backport [https://github.com/vim/vim/commit/868ad62cb8bf8038322eab2badd31bd98b02b9df]
+
+Backport Changes:
+- Omitted src/version.c because the Scarthgap recipe remains at Vim 9.1.1683;
+  the upstream version-table hunk targets Vim 9.2 and conflicted during
+  cherry-pick, while the runtime and test changes applied unchanged.
+
+Signed-off-by: thinca <thinca@gmail.com>
+Signed-off-by: Christian Brabandt <cb@256bit.org>
+(cherry picked from commit 868ad62cb8bf8038322eab2badd31bd98b02b9df)
+Signed-off-by: Devansh Patel <devanshp@cisco.com>
+---
+ runtime/autoload/python3complete.vim | 3 +++
+ runtime/autoload/pythoncomplete.vim  | 3 +++
+ src/testdir/test_popup.vim           | 4 ++++
+ 3 files changed, 10 insertions(+)
+
+diff --git a/runtime/autoload/python3complete.vim b/runtime/autoload/python3complete.vim
+index a0314242b..bdabf62c8 100644
+--- a/runtime/autoload/python3complete.vim
++++ b/runtime/autoload/python3complete.vim
+@@ -158,6 +158,9 @@ class Completer(object):
+        self.parser = PyParser()
+ 
+     def evalsource(self,text,line=0):
++        # vim is imported locally in vimpy3complete(); re-import here so the
++        # vim.eval() below works (otherwise NameError, silently caught).
++        import vim
+         sc = self.parser.parse(text,line)
+         try: allow_imports = int(
+           vim.eval("get(g:, 'pythoncomplete_allow_import', 0)"))
+diff --git a/runtime/autoload/pythoncomplete.vim b/runtime/autoload/pythoncomplete.vim
+index 39b1efd29..761488244 100644
+--- a/runtime/autoload/pythoncomplete.vim
++++ b/runtime/autoload/pythoncomplete.vim
+@@ -172,6 +172,9 @@ class Completer(object):
+        self.parser = PyParser()
+ 
+     def evalsource(self,text,line=0):
++        # vim is imported locally in vimcomplete(); re-import here so the
++        # vim.eval() below works (otherwise NameError, silently caught).
++        import vim
+         sc = self.parser.parse(text,line)
+         try: allow_imports = int(
+           vim.eval("get(g:, 'pythoncomplete_allow_import', 0)"))
+diff --git a/src/testdir/test_popup.vim b/src/testdir/test_popup.vim
+index fac2a7592..55c2f232d 100644
+--- a/src/testdir/test_popup.vim
++++ b/src/testdir/test_popup.vim
+@@ -723,6 +723,9 @@ func Test_popup_and_preview_autocommand()
+     au!
+     au BufAdd * nested tab sball
+   augroup END
++  " Let pythoncomplete follow the buffer's 'import os' (off by default
++  " since v9.2.0561) so 'os.' can be completed.
++  let g:pythoncomplete_allow_import = 1
+   set omnifunc=pythoncomplete#Complete
+   call setline(1, 'import os')
+   " make the line long
+@@ -745,6 +748,7 @@ func Test_popup_and_preview_autocommand()
+   augroup END
+   augroup! MyBufAdd
+   bw!
++  unlet g:pythoncomplete_allow_import
+ endfunc
+ 
+ func s:run_popup_and_previewwindow_dump(lines, dumpfile)
diff --git a/meta/recipes-support/vim/vim.inc b/meta/recipes-support/vim/vim.inc
index a4f8162d31..ced48eb0c1 100644
--- a/meta/recipes-support/vim/vim.inc
+++ b/meta/recipes-support/vim/vim.inc
@@ -34,6 +34,7 @@ SRC_URI = "git://github.com/vim/vim.git;branch=master;protocol=https \
            file://CVE-2026-46483.patch \
            file://CVE-2026-28420.patch \
            file://CVE-2026-52858.patch \
+           file://CVE-2026-52858-regression.patch \
            file://CVE-2026-52859.patch \
            file://CVE-2026-52860.patch \
            file://CVE-2026-28422.patch \
-- 
2.35.6