diff options
| author | Christian Brabandt <cb@256bit.org> | 2023-11-30 11:32:18 +0100 |
|---|---|---|
| committer | Christian Brabandt <cb@256bit.org> | 2023-12-01 18:58:51 +0100 |
| commit | abfa13ebe92d81aaf66669c428d767847b577453 (patch) | |
| tree | 5b6d87d9c13568960be219188c849a4c41ba315c | |
| parent | b39b240c386a5a29241415541f1c99e2e6b8ce47 (diff) | |
patch 9.0.2143: [security]: buffer-overflow in ex_substitutev9.0.2143
Problem: [security]: buffer-overflow in ex_substitute
Solution: clear memory after allocating
When allocating the new_start pointer in ex_substitute() the memory
pointer points to some garbage that the following for loop in
ex_cmds.c:4743 confuses and causes it to accessing the new_start pointer
beyond it's size, leading to a buffer-overlow.
So fix this by using alloc_clear() instead of alloc(), which will
clear the memory by NUL and therefore cause the loop to terminate
correctly.
Reported by @henices, thanks!
closes: #13596
Signed-off-by: Christian Brabandt <cb@256bit.org>
| -rw-r--r-- | src/ex_cmds.c | 4 | ||||
| -rw-r--r-- | src/testdir/crash/poc_ex_substitute | bin | 0 -> 135 bytes | |||
| -rw-r--r-- | src/testdir/test_crash.vim | 13 | ||||
| -rw-r--r-- | src/version.c | 2 |
4 files changed, 16 insertions, 3 deletions
diff --git a/src/ex_cmds.c b/src/ex_cmds.c index a08682b071..e311fa8e7a 100644 --- a/src/ex_cmds.c +++ b/src/ex_cmds.c @@ -4650,7 +4650,7 @@ ex_substitute(exarg_T *eap) * too many calls to alloc()/free()). */ new_start_len = needed_len + 50; - if ((new_start = alloc(new_start_len)) == NULL) + if ((new_start = alloc_clear(new_start_len)) == NULL) goto outofmem; *new_start = NUL; new_end = new_start; @@ -4667,7 +4667,7 @@ ex_substitute(exarg_T *eap) if (needed_len > (int)new_start_len) { new_start_len = needed_len + 50; - if ((p1 = alloc(new_start_len)) == NULL) + if ((p1 = alloc_clear(new_start_len)) == NULL) { vim_free(new_start); goto outofmem; diff --git a/src/testdir/crash/poc_ex_substitute b/src/testdir/crash/poc_ex_substitute Binary files differnew file mode 100644 index 0000000000..bcf1286512 --- /dev/null +++ b/src/testdir/crash/poc_ex_substitute diff --git a/src/testdir/test_crash.vim b/src/testdir/test_crash.vim index 1d4f435e4d..49e712a901 100644 --- a/src/testdir/test_crash.vim +++ b/src/testdir/test_crash.vim @@ -117,7 +117,7 @@ func Test_crash1_2() " The following used to crash Vim let opts = #{cmd: 'sh'} let vim = GetVimProg() - let result = 'X_crash1_1_result.txt' + let result = 'X_crash1_2_result.txt' let buf = RunVimInTerminal('sh', opts) @@ -149,6 +149,17 @@ func Test_crash1_2() \ ' ; echo "crash 4: [OK]" >> '.. result .. "\<cr>") call TermWait(buf, 150) + let file = 'crash/poc_ex_substitute' + let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'" + let args = printf(cmn_args, vim, file) + " just make sure it runs, we don't care about the resulting echo + call term_sendkeys(buf, args .. "\<cr>") + " There is no output generated in Github CI for the asan clang build. + " so just skip generating the ouput. + " call term_sendkeys(buf, args .. + " \ ' && echo "crash 5: [OK]" >> '.. result .. "\<cr>") + call TermWait(buf, 150) + " clean up exe buf .. "bw!" diff --git a/src/version.c b/src/version.c index 28325a7fa4..efa9dcd32d 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 */ /**/ + 2143, +/**/ 2142, /**/ 2141, |