From: Pádraig Brady <P@draigBrady.com>
Date: Sun, 22 Jun 2025 15:40:04 +0000 (+0100)
Subject: stty: stricter floating point parsing
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d35b3c0e56bd556c90dc98c3e5e2e7289b0eb0d;p=thirdparty%2Fcoreutils.git

stty: stricter floating point parsing

* src/stty.c (string_to_baud): Disallow extraneous characters
after floating point numbers.
* tests/stty/stty-invalid.sh: Add test cases.
---

diff --git a/src/stty.c b/src/stty.c
index 561de1c1a0..0163ea48aa 100644
--- a/src/stty.c
+++ b/src/stty.c
@@ -2200,25 +2200,24 @@ string_to_baud (char const *arg)
       c = *ep++;
       if (c)
         {
-          c -= '0';
-          if (c > 9)
+          unsigned char d = c - '0';
+          if (d > 5)
+            value++;
+          else if (d == 5)
             {
-              return (speed_t) -1; /* Garbage after otherwise valid number */
-            }
-          else if (c > 5)
-            {
-              value++;
-            }
-          else if (c == 5)
-            {
-              while ((c = *ep++) == '0')
-              ; /* Skip zeroes after .5 */
+              while ((c = *ep++) == '0'); /* Skip zeroes after .5 */
 
-              if (c >= '1' && c <= '9')
-                value++;                /* Nonzero digit, round up */
+              if (c)
+                value++;                /* Nonzero, round up */
               else
                 value += (value & 1);   /* Exactly in the middle, round even */
             }
+
+          while (c_isdigit (c)) /* Skip remaining digits.  */
+            c = *ep++;
+
+          if (c)
+            return (speed_t) -1; /* Garbage after otherwise valid number */
         }
     }
   else if (c)
diff --git a/tests/stty/stty-invalid.sh b/tests/stty/stty-invalid.sh
index a1442a82d0..868ed1d16a 100755
--- a/tests/stty/stty-invalid.sh
+++ b/tests/stty/stty-invalid.sh
@@ -55,7 +55,8 @@ fi
 # so restrict tests here to invalid numbers
 # We simulate unsupported numbers in a separate "LD_PRELOAD" test.
 WRAP_9600="$(expr $ULONG_OFLOW - 9600)"
-for speed in 9600.. ++9600 -$WRAP_9600 --$WRAP_9600 0x2580 96E2; do
+for speed in 9599.. 9600.. 9600.5. 9600.50. 9600.0. ++9600 \
+             -$WRAP_9600 --$WRAP_9600 0x2580 96E2 9600,0 '9600.0 '; do
   returns_ 1 stty ispeed "$speed" || fail=1
 done