diff options
Diffstat (limited to 'libc')
| -rw-r--r-- | libc/unistd/opendir.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/libc/unistd/opendir.c b/libc/unistd/opendir.c index afa3ea0ee..f178bc669 100644 --- a/libc/unistd/opendir.c +++ b/libc/unistd/opendir.c @@ -92,6 +92,9 @@ static struct dirent* _readdir_unlocked(DIR* dir) { struct dirent* entry; +#ifndef NDEBUG + unsigned reclen; +#endif if ( !dir->_DIR_avail ) { @@ -115,15 +118,18 @@ _readdir_unlocked(DIR* dir) if (((long)(void*)entry & 3) != 0) return NULL; - if ( (unsigned)entry->d_reclen > sizeof(*entry) || - entry->d_reclen <= offsetof(struct dirent, d_name) ) +#ifndef NDEBUG + // paranoid testing of the interface with the kernel getdents64 system call + reclen = offsetof(struct dirent, d_name) + strlen(entry->d_name) + 1; + if ( reclen > sizeof(*entry) || reclen <= offsetof(struct dirent, d_name) ) goto Bad; - if ( (char*)entry + entry->d_reclen > (char*)dir->_DIR_buff + sizeof(dir->_DIR_buff) ) + if ( (char*)entry + reclen > (char*)dir->_DIR_buff + sizeof(dir->_DIR_buff) ) goto Bad; - if ( !memchr( entry->d_name, 0, entry->d_reclen - offsetof(struct dirent, d_name)) ) + if ( !memchr( entry->d_name, 0, reclen - offsetof(struct dirent, d_name)) ) goto Bad; +#endif dir->_DIR_next = (struct dirent*)((char*)entry + entry->d_reclen); dir->_DIR_avail -= entry->d_reclen; |