[glibc] locale: Use correct buffer size for utf8_sequence_error [BZ #19444]

[glibc] locale: Use correct buffer size for utf8_sequence_error [BZ #19444]

[Adhemerval Zanella]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=0b3503e2e19602db9cda47915d19a26c00f59bb1

commit 0b3503e2e19602db9cda47915d19a26c00f59bb1
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Thu Dec 29 09:57:59 2022 -0300

    locale: Use correct buffer size for utf8_sequence_error [BZ #19444]
    
    The buffer used by snprintf might not be large enough for all possible
    inputs, as indicated by gcc with -O1:
    
    ../locale/programs/linereader.c: In function ‘utf8_sequence_error’:
    ../locale/programs/linereader.c:713:58: error: ‘%02x’ directive output
    may be truncated writing between 2 and 8 bytes into a region of size
    between 1 and 13 [-Werror=format-truncation=]
      713 |     snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
          |                                                          ^~~~
    ../locale/programs/linereader.c:713:34: note: directive argument in the
    range [0, 2147483647]
      713 |     snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
          |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../locale/programs/linereader.c:713:5: note: ‘snprintf’ output between
    20 and 38 bytes into a destination of size 30
      713 |     snprintf (buf, sizeof (buf), "0x%02x 0x%02x 0x%02x 0x%02x",
          |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      714 |               ch1, ch2, ch3, ch4);
          |               ~~~~~~~~~~~~~~~~~~~
    
    Checked on x86_64-linux-gnu.
    Reviewed-by: Carlos O'Donell <carlos@redhat.com>

Diff:
---
 locale/programs/linereader.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/locale/programs/linereader.c b/locale/programs/linereader.c
index 17099af744..f8c49ac06f 100644
--- a/locale/programs/linereader.c
+++ b/locale/programs/linereader.c
@@ -701,7 +701,7 @@ static bool
 utf8_sequence_error (struct linereader *lr, uint8_t ch1, int ch2, int ch3,
 		     int ch4)
 {
-  char buf[30];
+  char buf[38];
 
   if (ch2 < 0)
     snprintf (buf, sizeof (buf), "0x%02x", ch1);