[git commit master] lift printf field width limit

Bernhard Reutner-Fischer rep.dot.nop at gmail.com
Wed Mar 17 13:54:04 UTC 2010


commit: http://git.uclibc.org/uClibc/commit/?id=266aaaf46e136d63532a797fd8604e30d4350443
branch: http://git.uclibc.org/uClibc/commit/?id=refs/heads/master

uClibc mishandles printf field width limits larger than 40959, as a
result of misguided overflow-protection code.  This causes spurious test
failures with GNU coreutils, which depends on "%65536s" and "%20000000f"
working according to spec.

Signed-off-by: Michael Deutschmann <michael at talamasca.ocis.net>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop at gmail.com>
---
 libc/stdio/_vfprintf.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/libc/stdio/_vfprintf.c b/libc/stdio/_vfprintf.c
index f288cb5..6fa8ecb 100644
--- a/libc/stdio/_vfprintf.c
+++ b/libc/stdio/_vfprintf.c
@@ -161,9 +161,6 @@
 /* Now controlled by uClibc_stdio.h. */
 /* #define __UCLIBC_HAS_GLIBC_CUSTOM_PRINTF__ */
 
-/* TODO -- move these to a configuration section? */
-#define MAX_FIELD_WIDTH		4095
-
 #ifdef __UCLIBC_MJN3_ONLY__
 #ifdef L_register_printf_function
 /* emit only once */
@@ -893,8 +890,11 @@ int attribute_hidden _ppfs_parsespec(ppfs_t *ppfs)
 	}
 	i = 0;
 	while (isdigit(*fmt)) {
-		if (i < MAX_FIELD_WIDTH) { /* Avoid overflow. */
+		if (i < INT_MAX / 10
+		    || (i == INT_MAX / 10 && (*fmt - '0') <= INT_MAX % 10)) {
 			i = (i * 10) + (*fmt - '0');
+		} else {
+			i = INT_MAX; /* best we can do... */
 		}
 		++fmt;
 	}
-- 
1.6.3.3



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