From 4e2f43f842ef5e253cc23383645adbaa03cedb86 Mon Sep 17 00:00:00 2001 From: Zack Weinberg Date: Wed, 7 Mar 2018 14:32:03 -0500 Subject: Use PRINTF_FORTIFY instead of _IO_FLAGS2_FORTIFY (bug 11319) The _chk variants of all of the printf functions become much simpler. This is the last thing that we needed _IO_acquire_lock_clear_flags2 for, so it can go as well. I took the opportunity to make the headers included and the names of all local variables consistent across all the affected files. Since we ultimately want to get rid of __no_long_double as well, it must be possible to get all of the nontrivial effects of the _chk functions by calling the _internal functions with appropriate flags. For most of the __(v)xprintf_chk functions, this is covered by PRINTF_FORTIFY plus some up-front argument checks that can be duplicated. However, __(v)sprintf_chk installs a custom jump table so that it can crash instead of overflowing the output buffer. This functionality is moved to __vsprintf_internal, which now has a 'maxlen' argument like __vsnprintf_internal; to get the unsafe behavior of ordinary (v)sprintf, pass -1 for that argument. obstack_printf_chk and obstack_vprintf_chk are no longer in the same file. As a side-effect of the unification of both fortified and non-fortified vdprintf initialization, this patch fixes bug 11319 for __dprintf_chk and __vdprintf_chk, which was previously fixed only for dprintf and vdprintf by the commit commit 7ca890b88e6ab7624afb1742a9fffb37ad5b3fc3 Author: Ulrich Drepper Date: Wed Feb 24 16:07:57 2010 -0800 Fix reporting of I/O errors in *dprintf functions. This patch adds a test case to avoid regressions. Tested for powerpc and powerpc64le. --- debug/vsprintf_chk.c | 69 ++++++---------------------------------------------- 1 file changed, 7 insertions(+), 62 deletions(-) (limited to 'debug/vsprintf_chk.c') diff --git a/debug/vsprintf_chk.c b/debug/vsprintf_chk.c index 53f0723..c1b1a8d 100644 --- a/debug/vsprintf_chk.c +++ b/debug/vsprintf_chk.c @@ -15,75 +15,20 @@ License along with the GNU C Library; if not, see . */ -#include -#include -#include "../libio/libioP.h" -#include "../libio/strfile.h" - - -static int _IO_str_chk_overflow (FILE *fp, int c) __THROW; - -static int -_IO_str_chk_overflow (FILE *fp, int c) -{ - /* When we come to here this means the user supplied buffer is - filled. */ - __chk_fail (); -} - - -static const struct _IO_jump_t _IO_str_chk_jumps libio_vtable = -{ - JUMP_INIT_DUMMY, - JUMP_INIT(finish, _IO_str_finish), - JUMP_INIT(overflow, _IO_str_chk_overflow), - JUMP_INIT(underflow, _IO_str_underflow), - JUMP_INIT(uflow, _IO_default_uflow), - JUMP_INIT(pbackfail, _IO_str_pbackfail), - JUMP_INIT(xsputn, _IO_default_xsputn), - JUMP_INIT(xsgetn, _IO_default_xsgetn), - JUMP_INIT(seekoff, _IO_str_seekoff), - JUMP_INIT(seekpos, _IO_default_seekpos), - JUMP_INIT(setbuf, _IO_default_setbuf), - JUMP_INIT(sync, _IO_default_sync), - JUMP_INIT(doallocate, _IO_default_doallocate), - JUMP_INIT(read, _IO_default_read), - JUMP_INIT(write, _IO_default_write), - JUMP_INIT(seek, _IO_default_seek), - JUMP_INIT(close, _IO_default_close), - JUMP_INIT(stat, _IO_default_stat), - JUMP_INIT(showmanyc, _IO_default_showmanyc), - JUMP_INIT(imbue, _IO_default_imbue) -}; - +#include int -___vsprintf_chk (char *s, int flags, size_t slen, const char *format, - va_list args) +___vsprintf_chk (char *s, int flag, size_t slen, const char *format, + va_list ap) { - _IO_strfile f; - int ret; -#ifdef _IO_MTSAFE_IO - f._sbf._f._lock = NULL; -#endif + /* For flag > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n + can only come from read-only format strings. */ + unsigned int mode = (flag > 0) ? PRINTF_FORTIFY : 0; if (slen == 0) __chk_fail (); - _IO_no_init (&f._sbf._f, _IO_USER_LOCK, -1, NULL, NULL); - _IO_JUMPS (&f._sbf) = &_IO_str_chk_jumps; - s[0] = '\0'; - _IO_str_init_static_internal (&f, s, slen - 1, s); - - /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n - can only come from read-only format strings. */ - if (flags > 0) - f._sbf._f._flags2 |= _IO_FLAGS2_FORTIFY; - - ret = __vfprintf_internal (&f._sbf._f, format, args, 0); - - *f._sbf._f._IO_write_ptr = '\0'; - return ret; + return __vsprintf_internal (s, slen, format, ap, mode); } ldbl_hidden_def (___vsprintf_chk, __vsprintf_chk) ldbl_strong_alias (___vsprintf_chk, __vsprintf_chk) -- cgit v1.1