diff options
author | Christian Brabandt <cb@256bit.org> | 2023-10-02 20:59:08 +0200 |
---|---|---|
committer | Christian Brabandt <cb@256bit.org> | 2023-10-02 20:59:47 +0200 |
commit | 3bd7fa12e146c6051490d048a4acbfba974eeb04 (patch) | |
tree | 16eef95edff7dd16bcf19fa40cd6d55e74e7a49c /src | |
parent | 6ee7b521fa7531ef356ececc8be7575c3800f872 (diff) |
patch 9.0.1969: [security] buffer-overflow in trunc_string()v9.0.1969
Problem: buffer-overflow in trunc_string()
Solution: Add NULL at end of buffer
Currently trunc_string() assumes that when the string is too long,
buf[e-1] will always be writeable. But that assumption may not always be
true. The condition currently looks like this
else if (e + 3 < buflen)
[...]
else
{
// can't fit in the "...", just truncate it
buf[e - 1] = NUL;
}
but this means, we may run into the last else clause with e still being
larger than buflen. So a buffer overflow occurs.
So instead of using `buf[e - 1]`, let's just always
truncate at `buf[buflen - 1]` which should always be writable.
Signed-off-by: Christian Brabandt <cb@256bit.org>
Diffstat (limited to 'src')
-rw-r--r-- | src/message.c | 2 | ||||
-rw-r--r-- | src/testdir/test_crash.vim | 7 | ||||
-rw-r--r-- | src/version.c | 2 |
3 files changed, 10 insertions, 1 deletions
diff --git a/src/message.c b/src/message.c index 2fc6cefa9d..83c8b4f4a0 100644 --- a/src/message.c +++ b/src/message.c @@ -353,7 +353,7 @@ trunc_string( else { // can't fit in the "...", just truncate it - buf[e - 1] = NUL; + buf[buflen - 1] = NUL; } } diff --git a/src/testdir/test_crash.vim b/src/testdir/test_crash.vim index a1da68ed4c..5c83e3a2f5 100644 --- a/src/testdir/test_crash.vim +++ b/src/testdir/test_crash.vim @@ -66,6 +66,12 @@ func Test_crash1() \ ' && echo "crash 7: [OK]" >> X_crash1_result.txt' .. "\<cr>") call TermWait(buf, 3000) + let file = 'crash/vim_msg_trunc_poc' + let args = printf(cmn_args, vim, file) + call term_sendkeys(buf, args .. + \ ' || echo "crash 8: [OK]" >> X_crash1_result.txt' .. "\<cr>") + call TermWait(buf, 3000) + " clean up exe buf .. "bw!" @@ -79,6 +85,7 @@ func Test_crash1() \ 'crash 5: [OK]', \ 'crash 6: [OK]', \ 'crash 7: [OK]', + \ 'crash 8: [OK]', \ ] call assert_equal(expected, getline(1, '$')) diff --git a/src/version.c b/src/version.c index 1be1462768..3056f35d7f 100644 --- a/src/version.c +++ b/src/version.c @@ -705,6 +705,8 @@ static char *(features[]) = static int included_patches[] = { /* Add new patch number below this line */ /**/ + 1969, +/**/ 1968, /**/ 1967, |