Mercurial > vim
diff src/ex_docmd.c @ 28741:b44f15083faf v8.2.4895
patch 8.2.4895: buffer overflow with invalid command with composing chars
Commit: https://github.com/vim/vim/commit/d88934406c5375d88f8f1b65331c9f0cab68cc6c
Author: Bram Moolenaar <Bram@vim.org>
Date: Fri May 6 20:38:47 2022 +0100
patch 8.2.4895: buffer overflow with invalid command with composing chars
Problem: Buffer overflow with invalid command with composing chars.
Solution: Check that the whole character fits in the buffer.
| author | Bram Moolenaar <Bram@vim.org> |
|---|---|
| date | Fri, 06 May 2022 21:45:02 +0200 |
| parents | 930f1bb1649d |
| children | d770568e6c98 |
line wrap: on
line diff
--- a/src/ex_docmd.c +++ b/src/ex_docmd.c @@ -3435,7 +3435,7 @@ append_command(char_u *cmd) STRCAT(IObuff, ": "); d = IObuff + STRLEN(IObuff); - while (*s != NUL && d - IObuff < IOSIZE - 7) + while (*s != NUL && d - IObuff + 5 < IOSIZE) { if (enc_utf8 ? (s[0] == 0xc2 && s[1] == 0xa0) : *s == 0xa0) { @@ -3443,6 +3443,8 @@ append_command(char_u *cmd) STRCPY(d, "<a0>"); d += 4; } + else if (d - IObuff + (*mb_ptr2len)(s) + 1 >= IOSIZE) + break; else MB_COPY_CHAR(s, d); }