Bug #81233 [Opn]: gcc catches number of memory issues by -Werror

Edit report at https://bugs.php.net/bug.php?id=81233&edit=1 ID: 81233 Updated by: dmitry@php.net Reported by: yohgaki at ohgaki dot net Summary: gcc catches number of memory issues by -Werror Status: Open Type: Bug Package: Compile Failure Operating System: Fedora 34 PHP Version: Irrelevant Block user comment: N Private report: N New Comment: The array bounds warning in JIT is definitely a false positive. I won't like to fix this in any way, because the warnings occurs in DynAsm header, borrowed from LuaJIT project. Previous Comments: ------------------------------------------------------------------------ [2021-07-08 22:19:38] yohgaki@php.net Compile errors are examples. I didn't try to find all of them and there may be real memory issues. It would be nice to use newer gcc for CI if it is possible. ------------------------------------------------------------------------ [2021-07-08 10:46:15] cmb@php.net > hash_gost has wrong prototype or wrong definition for 1st param. > Clearly a bug. Well, it might hint at a bug, but isn't a bug per se, since array parameters are degraded to pointers anway. This has been fixed a while ago in master[1], since apparently there is no actual bug. > It seems this strncpy does not consider null char. Certainly not clean (should probably be a memcpy()), but doesn't look like a real bug. > This may be false-positive, but out of bound access possibly. That would be something Dmitry should have a look at. [1] <https://github.com/php/php-src/commit/e0e3d9851ae517429d1bfc7eb2df9df917406d2c> ------------------------------------------------------------------------ [2021-07-08 01:24:42] yohgaki at ohgaki dot net Description: ------------ Newer gcc catches memory issues during compile time and raise warnings. Since 7.4, -Werror compile flag that makes warning to error, PHP cannot be compiled. Therefore, Fedora 34 cannot compile PHP from 7.4 to master. $ uname -a Linux dev 5.12.13-300.fc34.x86_64 #1 SMP Wed Jun 23 16:18:11 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux $ gcc --version gcc (GCC) 11.1.1 20210531 (Red Hat 11.1.1-3) There are number of issues catched by gcc. Followings are examples. hash_gost has wrong prototype or wrong definition for 1st param. Clearly a bug. ------------------ /home/yohgaki/git/oss/php.net/PHP-7.4/ext/hash/hash_gost.c:286:47: error: argument 1 of type 'unsigned char[32]' with mismatched bound [-Werror=array-parameter=] 286 | PHP_HASH_API void PHP_GOSTFinal(unsigned char digest[32], PHP_GOST_CTX *context) | ~~~~~~~~~~~~~~^~~~~~~~~~ In file included from /home/yohgaki/git/oss/php.net/PHP-7.4/ext/hash/hash_gost.c:21: /home/yohgaki/git/oss/php.net/PHP-7.4/ext/hash/php_hash_gost.h:35:33: note: previously declared as 'unsigned char[64]' 35 | PHP_HASH_API void PHP_GOSTFinal(unsigned char[64], PHP_GOST_CTX *); | ^~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors make: *** [Makefile:1119: ext/hash/hash_gost.lo] Error 1 make: *** Waiting for unfinished jobs.... ---------------------- It seems this strncpy does not consider null char. ---------------------- /home/yohgaki/git/oss/php.net/PHP-master/ext/pdo/pdo_dbh.c:85:9: error: 'strncpy' specified bound 6 equals destination size [-Werror=stringop-truncation] 85 | strncpy(*pdo_err, sqlstate, 6); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors ---------------------- This may be false-positive, but out of bound access possibly. It doesn't compile with -Werror anyway. ---------------------- /home/yohgaki/git/oss/php.net/PHP-master/ext/opcache/jit/dynasm/dasm_x86.h:127:19: error: array subscript -10 is outside array bounds of 'void *[36]' [-Werror=array-bounds] 127 | D->globals = gl - 10; /* Negative bias to compensate for locals. */ | ~~~^~~~ In file included from /home/yohgaki/git/oss/php.net/PHP-master/ext/opcache/jit/zend_jit.c:729: /home/yohgaki/git/oss/php.net/PHP-master/ext/opcache/jit/zend_jit_x86.dasc:143:14: note: while referencing 'dasm_labels' 143 | static void* dasm_labels[zend_lb_MAX]; | ^~~~~~~~~~~ cc1: all warnings being treated as errors ---------------------- ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=81233&edit=1