* doprnt.c (doprnt): Omit useless test; int overflow check (Bug#8545).

2 files changed, 10 insertions, 2 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 555fb9589f5..14727d403c2 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2011-04-28  Paul Eggert  <eggert@cs.ucla.edu>
+
+        * doprnt.c (doprnt): Omit useless test; int overflow check (Bug#8545).
+
 2011-04-28  Juanma Barranquero  <lekktu@gmail.com>
 
         * w32.c (init_environment): Warn about defaulting HOME to C:\.
diff --git a/src/doprnt.c b/src/doprnt.c
index 63dba9f5850..eac1796c496 100644
--- a/src/doprnt.c
+++ b/src/doprnt.c
@@ -198,8 +198,12 @@ doprnt (char *buffer, register size_t bufsize, const char *format,
                   while (fmt < format_end
                          && '0' <= fmt[1] && fmt[1] <= '9')
                     {
-                      if (n >= SIZE_MAX / 10
-                          || n * 10 > SIZE_MAX - (fmt[1] - '0'))
+                      /* Avoid int overflow, because many sprintfs seriously
+                         mess up with widths or precisions greater than
+                         INT_MAX.  Avoid size_t overflow, since our counters
+                         use size_t.  This test is slightly conservative, for
+                         speed and simplicity.  */
+                      if (n >= min (INT_MAX, SIZE_MAX) / 10)
                         error ("Format width or precision too large");
                       n = n * 10 + fmt[1] - '0';
                       *string++ = *++fmt;