ext/mbstring: fix new_value length check #10532
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Thanks! I seem to remember @cmb69 once commented on that piece of code, saying that the check didn't make sense... thanks for figuring out why it was that way. |
alexdowad
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Feb 7, 2023
Commit 8bbd095 added a check rejecting empty strings; in the merge commiot 379d9a1 however it was changed to a NULL check, one that did not make sense because ZSTR_VAL() is guaranteed to never be NULL; the length check was accidently removed by that merge commit. This bug was found by GCC's -Waddress warning: ext/mbstring/mbstring.c:748:27: warning: the comparison will always evaluate as ‘true’ for the address of ‘val’ will never be NULL [-Waddress] 748 | if (!new_value || !ZSTR_VAL(new_value)) { | ^
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Commit 8bbd095 added a check rejecting empty strings; in the merge commiot 379d9a1 however it was changed to a NULL check, one that did not make sense because ZSTR_VAL() is guaranteed to never be NULL; the length check was accidently removed by that merge commit.
This bug was found by GCC's -Waddress warning:
ext/mbstring/mbstring.c:748:27: warning: the comparison will always evaluate as ‘true’ for the address of ‘val’ will never be NULL [-Waddress]
748 | if (!new_value || !ZSTR_VAL(new_value)) {
| ^