vim-patch:partial:9.2.0315: missing bound-checks (#39334)

Problem:  missing bound-checks
Solution: Add defensive guards against potential buffer overflow
          (Yasuhiro Matsumoto)

Add bounds checking and integer overflow guards across multiple files
as a defensive measure. While these code paths are unlikely to be
exploitable in practice, the guards prevent undefined behavior in
edge cases.

- libvterm/vterm.c: use heap tmpbuffer instead of stack buffer in
  vsprintf() fallback path
- channel.c: validate len in channel_consume() before mch_memmove()
- spell.c: use long instead of int for addlen to avoid signed overflow
  in size_t subtraction
- alloc.c: add SIZE_MAX overflow check in ga_grow_inner() before
  itemsize multiplication
- list.c: add overflow check before count * sizeof(listitem_T)
- popupwin.c: add overflow check before width * height allocation
- insexpand.c: add overflow check before compl_num_bests multiplication
- regexp_bt.c: replace sprintf() with vim_snprintf() in regprop()
- spellfile.c: use SIZE_MAX instead of LONG_MAX for allocation overflow
  check

closes: vim/vim#19904

https://github.com/vim/vim/commit/8d23fcb603d8f8938ce0023086326a5db6780ea2

Co-authored-by: Yasuhiro Matsumoto <mattn.jp@gmail.com>

0 files changed, 0 insertions, 0 deletions