Commit: patch 9.1.1143: illegal memory access when putting a register

[Christian Brabandt]

patch 9.1.1143: illegal memory access when putting a register

Commit: https://github.com/vim/vim/commit/e0029daa3599529d9d438cc51c7ada8580297a39
Author: Christian Brabandt <c...@256bit.org>
Date: Sun Feb 23 20:01:54 2025 +0100

patch 9.1.1143: illegal memory access when putting a register

Problem: illegal memory access when putting a register
Solution: make sure cursor column doesn't become negative

Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/register.c b/src/register.c
index a9630f8ef..ea54e202e 100644
--- a/src/register.c
+++ b/src/register.c
@@ -2249,7 +2249,7 @@ error:
// Put the '] mark on the first byte of the last inserted character.
// Correct the length for change in indent.
curbuf->b_op_end.lnum = new_lnum;
- col = (colnr_T)y_array[y_size - 1].length - lendiff;
+ col = MAX(0, (colnr_T)y_array[y_size - 1].length - lendiff);
if (col > 1)
{
curbuf->b_op_end.col = col - 1;
diff --git a/src/testdir/test_registers.vim b/src/testdir/test_registers.vim
index ee59ecb30..252445377 100644
--- a/src/testdir/test_registers.vim
+++ b/src/testdir/test_registers.vim
@@ -1123,4 +1123,21 @@ func Test_register_redir_display()
call setreg(1, a[0], a[1])
endfunc

+" this caused an illegal memory access and a crash
+func Test_register_cursor_column_negative()
+ CheckRunVimInTerminal
+ let script =<< trim END
+ f XREGISTER
+ call setline(1, 'abcdef a')
+ call setreg("a", "
", 'c')
+ call cursor(1, 7)
+ call feedkeys("i\<C-R>\<C-P>azyx$#\<esc>", 't')
+ END
+ call writefile(script, 'XRegister123', 'D')
+ let buf = RunVimInTerminal('-S XRegister123', {})
+ call term_sendkeys(buf, "\<c-g>")
+ call WaitForAssert({-> assert_match('XREGISTER', term_getline(buf, 19))})
+ call StopVimInTerminal(buf)
+endfunc
+
" vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index 2dfd4c83e..07bede551 100644
--- a/src/version.c
+++ b/src/version.c
@@ -704,6 +704,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1143,
/**/
1142,
/**/