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Fix GH-13984: Buffer size is now checked before memcmp #13991

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2 changes: 1 addition & 1 deletion ext/pdo_sqlite/sqlite_driver.c
Original file line number Diff line number Diff line change
Expand Up @@ -751,7 +751,7 @@ static char *make_filename_safe(const char *filename)
}
return estrdup(filename);
}
if (*filename && memcmp(filename, ":memory:", sizeof(":memory:"))) {
if (*filename && (sizeof(filename) != sizeof(":memory:") || memcmp(filename, ":memory:", sizeof(":memory:")) != 0)) {
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)))) was too hard to see, so I added != 0. The meaning remains the same.

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This is wrong, sizeof(filename) is not the length, it is the size of the pointer.
I also think the != 0 addition is wrong for memcmp?

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why bothering with memcmp anyway ? why not just any str*cmp ?

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@nielsdos

This is wrong, sizeof(filename) is not the length, it is the size of the pointer.

Right. I entered sizeof with the intention of strlen...

I also think the != 0 addition is wrong for memcmp?

Since it becomes true when 1 and -1, it seems to be the same because it becomes true when != 0, but am I wrong?

@devnexen

why bothering with memcmp anyway ? why not just any str*cmp ?

I thought I had to convert it to zend_string, but there were some that could be used as char, so I fixed it.

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Right, I misread the original condition. So !=0 is fine.

char *fullpath = expand_filepath(filename, NULL);

if (!fullpath) {
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16 changes: 16 additions & 0 deletions ext/pdo_sqlite/tests/gh13991.phpt
Original file line number Diff line number Diff line change
@@ -0,0 +1,16 @@
--TEST--
Fix GH-13984: Buffer size is now checked before memcmp
--EXTENSIONS--
pdo_sqlite
--FILE--
<?php
$dbfile = 'z.db';
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@SakiTakamachi SakiTakamachi Apr 17, 2024

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I did this because specifying the absolute path would make the string longer and not be overloaded.

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Hm right... This can clash with local files though, so perhaps it's better to use 13991 as filename?

$db = new PDO('sqlite:' . $dbfile, null, null, [PDO::ATTR_PERSISTENT => true]);
echo 'done!';
?>
--CLEAN--
<?php
@unlink(getcwd() . '/z.db');
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Is there a better way?

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We should be careful somehow that we don't destroy files or users running the tests.

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Changed to skip if a file with the same name already exists.

?>
--EXPECT--
done!
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