lib/clobber.c

ソースコードを見る。

関数
void	clobber_region (const char *fn, unsigned int line, char *dest, size_t len)
	In developer builds, clobber a region of memory.
変数
const char *	global_clobber_region_function
unsigned int	global_clobber_region_line

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関数

void clobber_region	(	const char *	fn,
		unsigned int	line,
		char *	dest,
		size_t	len
	)

In developer builds, clobber a region of memory.

If we think a string buffer is longer than it really is, this ought to make the failure obvious, by segfaulting (if in the heap) or by killing the return address (on the stack), or by trapping under a memory debugger.

This is meant to catch possible string overflows, even if the actual string copied is not big enough to cause an overflow.

In addition, under Valgrind the buffer is marked as uninitialized.

clobber.c の 42 行で定義されています。

参照先 global_clobber_region_function・global_clobber_region_line.

参照元 alpha_strcpy_fn()・cli_initialise()・NewInBuffer()・NewOutBuffer()・pull_string_fn()・push_string_fn()・safe_strcat_fn()・safe_strcpy_fn()・smbd_process()・StrnCpy_fn()・strncpyn().

{
#ifdef DEVELOPER
        global_clobber_region_function = fn;
        global_clobber_region_line = line;

        /* F1 is odd and 0xf1f1f1f1 shouldn't be a valid pointer */
        memset(dest, 0xF1, len);
#ifdef VALGRIND
        /* Even though we just wrote to this, from the application's
         * point of view it is not initialized.
         *
         * (This is not redundant with the clobbering above.  The
         * marking might not actually take effect if we're not running
         * under valgrind.) */
#if defined(VALGRIND_MAKE_MEM_UNDEFINED)
        VALGRIND_MAKE_MEM_UNDEFINED(dest, len);
#elif defined(VALGRIND_MAKE_WRITABLE)
        VALGRIND_MAKE_WRITABLE(dest, len);
#endif
#endif /* VALGRIND */
#endif /* DEVELOPER */
}

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変数

const char* global_clobber_region_function

clobber.c の 25 行で定義されています。

参照元 clobber_region()・smb_panic().

unsigned int global_clobber_region_line

clobber.c の 26 行で定義されています。

参照元 clobber_region()・smb_panic().

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