[U-Boot] [PATCH 1/3] vsprintf.c: Always enable CONFIG_SYS_VSNPRINTF
Tom Rini
trini at konsulko.com
Thu Jan 14 19:02:03 CET 2016
Enabling this function always removes some class of string saftey issues.
The size change here in general is about 400 bytes and this seems a reasonable
trade-off.
Cc: Peng Fan <peng.fan at nxp.com>
Cc: Peter Robinson <pbrobinson at gmail.com>
Cc: Fabio Estevam <fabio.estevam at freescale.com>
Cc: Adrian Alonso <aalonso at freescale.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Hans de Goede <hdegoede at redhat.com>
Signed-off-by: Tom Rini <trini at konsulko.com>
---
I ran my usual world build of buildman with size comparison options this time
to test this out. The only exception to the general size change here are
q8_a23_tablet_800x480 and gt90h_v4 both in the non-SPL case. These both grow
by 3780 bytes in the non-SPL case. In all cases except those two, when paired
with the gzwrite patch I posted yesterday we gain all of that back, or more.
---
README | 9 ---------
configs/bayleybay_defconfig | 1 -
configs/chromebook_link_defconfig | 1 -
configs/chromebox_panther_defconfig | 1 -
configs/coreboot-x86_defconfig | 1 -
configs/crownbay_defconfig | 1 -
configs/galileo_defconfig | 1 -
configs/minnowmax_defconfig | 1 -
configs/qemu-x86_defconfig | 1 -
configs/sandbox_defconfig | 1 -
include/vsprintf.h | 12 ------------
lib/Kconfig | 9 ---------
lib/vsprintf.c | 12 ------------
13 files changed, 51 deletions(-)
diff --git a/README b/README
index 5ac2d44..b7ce63d 100644
--- a/README
+++ b/README
@@ -890,15 +890,6 @@ The following options need to be configured:
'Sane' compilers will generate smaller code if
CONFIG_PRE_CON_BUF_SZ is a power of 2
-- Safe printf() functions
- Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
- the printf() functions. These are defined in
- include/vsprintf.h and include snprintf(), vsnprintf() and
- so on. Code size increase is approximately 300-500 bytes.
- If this option is not given then these functions will
- silently discard their buffer size argument - this means
- you are not getting any overflow checking in this case.
-
- Boot Delay: CONFIG_BOOTDELAY - in seconds
Delay before automatically booting the default image;
set to -1 to disable autoboot.
diff --git a/configs/bayleybay_defconfig b/configs/bayleybay_defconfig
index f462e05..0879d1e 100644
--- a/configs/bayleybay_defconfig
+++ b/configs/bayleybay_defconfig
@@ -37,4 +37,3 @@ CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
diff --git a/configs/chromebook_link_defconfig b/configs/chromebook_link_defconfig
index dbfbb97..baa0ed8 100644
--- a/configs/chromebook_link_defconfig
+++ b/configs/chromebook_link_defconfig
@@ -38,5 +38,4 @@ CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
CONFIG_TPM=y
diff --git a/configs/chromebox_panther_defconfig b/configs/chromebox_panther_defconfig
index ed4428f..c368cc0 100644
--- a/configs/chromebox_panther_defconfig
+++ b/configs/chromebox_panther_defconfig
@@ -33,5 +33,4 @@ CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
CONFIG_TPM=y
diff --git a/configs/coreboot-x86_defconfig b/configs/coreboot-x86_defconfig
index cd2be18..fda0db2 100644
--- a/configs/coreboot-x86_defconfig
+++ b/configs/coreboot-x86_defconfig
@@ -25,5 +25,4 @@ CONFIG_TPM_TIS_LPC=y
CONFIG_USB=y
CONFIG_DM_USB=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
CONFIG_TPM=y
diff --git a/configs/crownbay_defconfig b/configs/crownbay_defconfig
index 932d9ec..6bc4b8d 100644
--- a/configs/crownbay_defconfig
+++ b/configs/crownbay_defconfig
@@ -36,4 +36,3 @@ CONFIG_DM_USB=y
CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
diff --git a/configs/galileo_defconfig b/configs/galileo_defconfig
index 0604aa7..925d3ee 100644
--- a/configs/galileo_defconfig
+++ b/configs/galileo_defconfig
@@ -28,4 +28,3 @@ CONFIG_TIMER=y
CONFIG_USB=y
CONFIG_DM_USB=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
diff --git a/configs/minnowmax_defconfig b/configs/minnowmax_defconfig
index 864fd1b..af6a8ec 100644
--- a/configs/minnowmax_defconfig
+++ b/configs/minnowmax_defconfig
@@ -39,4 +39,3 @@ CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
diff --git a/configs/qemu-x86_defconfig b/configs/qemu-x86_defconfig
index 8c86931..b0c935c 100644
--- a/configs/qemu-x86_defconfig
+++ b/configs/qemu-x86_defconfig
@@ -30,4 +30,3 @@ CONFIG_VIDEO_VESA=y
CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
CONFIG_FRAMEBUFFER_VESA_MODE_111=y
CONFIG_USE_PRIVATE_LIBGCC=y
-CONFIG_SYS_VSNPRINTF=y
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index 731fc25..caa7336 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -76,7 +76,6 @@ CONFIG_USB_EMUL=y
CONFIG_USB_STORAGE=y
CONFIG_USB_KEYBOARD=y
CONFIG_SYS_USB_EVENT_POLL=y
-CONFIG_SYS_VSNPRINTF=y
CONFIG_CMD_DHRYSTONE=y
CONFIG_TPM=y
CONFIG_LZ4=y
diff --git a/include/vsprintf.h b/include/vsprintf.h
index b5bc9c1..376f5dd 100644
--- a/include/vsprintf.h
+++ b/include/vsprintf.h
@@ -124,7 +124,6 @@ int sprintf(char *buf, const char *fmt, ...)
int vsprintf(char *buf, const char *fmt, va_list args);
char *simple_itoa(ulong i);
-#ifdef CONFIG_SYS_VSNPRINTF
/**
* Format a string and place it in a buffer
*
@@ -199,17 +198,6 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
* See the vsprintf() documentation for format string extensions over C99.
*/
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
-#else
-/*
- * Use macros to silently drop the size parameter. Note that the 'cn'
- * versions are the same as the 'n' versions since the functions assume
- * there is always enough buffer space when !CONFIG_SYS_VSNPRINTF
- */
-#define snprintf(buf, size, fmt, args...) sprintf(buf, fmt, ##args)
-#define scnprintf(buf, size, fmt, args...) sprintf(buf, fmt, ##args)
-#define vsnprintf(buf, size, fmt, args...) vsprintf(buf, fmt, ##args)
-#define vscnprintf(buf, size, fmt, args...) vsprintf(buf, fmt, ##args)
-#endif /* CONFIG_SYS_VSNPRINTF */
/**
* print_grouped_ull() - print a value with digits grouped by ','
diff --git a/lib/Kconfig b/lib/Kconfig
index 9d580e4..46d7034 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -27,15 +27,6 @@ config SYS_HZ
get_timer() must operate in milliseconds and this option must be
set to 1000.
-config SYS_VSNPRINTF
- bool "Enable safe version of sprintf()"
- help
- Since sprintf() can overflow its buffer, it is common to use
- snprintf() instead, which knows the buffer size and can avoid
- overflow. However, this does increase code size slightly (for
- Thumb-2, about 420 bytes). Enable this option for safety when
- using sprintf() with data you do not control.
-
config USE_TINY_PRINTF
bool "Enable tiny printf() version"
help
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 24167a1..874a295 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -141,7 +141,6 @@ static noinline char *put_dec(char *buf, uint64_t num)
#define SMALL 32 /* Must be 32 == 0x20 */
#define SPECIAL 64 /* 0x */
-#ifdef CONFIG_SYS_VSNPRINTF
/*
* Macro to add a new character to our output string, but only if it will
* fit. The macro moves to the next character position in the output string.
@@ -151,9 +150,6 @@ static noinline char *put_dec(char *buf, uint64_t num)
*(str) = (ch); \
++str; \
} while (0)
-#else
-#define ADDCH(str, ch) (*(str)++ = (ch))
-#endif
static char *number(char *buf, char *end, u64 num,
int base, int size, int precision, int type)
@@ -441,13 +437,11 @@ static int vsnprintf_internal(char *buf, size_t size, const char *fmt,
/* 't' added for ptrdiff_t */
char *end = buf + size;
-#ifdef CONFIG_SYS_VSNPRINTF
/* Make sure end is always >= buf - do we want this in U-Boot? */
if (end < buf) {
end = ((void *)-1);
size = end - buf;
}
-#endif
str = buf;
for (; *fmt ; ++fmt) {
@@ -609,21 +603,16 @@ repeat:
flags);
}
-#ifdef CONFIG_SYS_VSNPRINTF
if (size > 0) {
ADDCH(str, '\0');
if (str > end)
end[-1] = '\0';
--str;
}
-#else
- *str = '\0';
-#endif
/* the trailing null byte doesn't count towards the total */
return str - buf;
}
-#ifdef CONFIG_SYS_VSNPRINTF
int vsnprintf(char *buf, size_t size, const char *fmt,
va_list args)
{
@@ -666,7 +655,6 @@ int scnprintf(char *buf, size_t size, const char *fmt, ...)
return i;
}
-#endif /* CONFIG_SYS_VSNPRINT */
/**
* Format a string and place it in a buffer (va_list version)
--
2.6.4
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