Bug #96074 mysqldump werror=format-truncation

• Submitted: 2 Jul 2019 11:48
• Modified: 12 Jul 2019 18:27
• Reporter: Tor Didriksen
• Status: Closed
• Category: MySQL Server: Compiling
• Severity: S3 (Non-critical)
• Version: 8.0.18
• OS: Any
• CPU Architecture: Any

[2 Jul 2019 11:48] Tor Didriksen

Description:
client/mysqldump.cc: In function void dump_table(char*, char*):
client/mysqldump.cc:3891:16: error: %s directive output may be truncated writing up to 194 bytes into a region of size 169 [-Werror=format-truncation=]
client/mysqldump.cc:3538:36:
   result_table = quote_name(table, table_buff, 1);
                                    ~~~~~~~~~~
client/mysqldump.cc:3891:16:
                "%s: Error %d: %s when dumping table %s at row: %ld\n",
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
client/mysqldump.cc:3891:16: note: using the range [-9223372036854775808, 9223372036854775807] for directive argument
client/mysqldump.cc:3890:15: note: snprintf output 43 or more bytes (assuming 237) into a destination of size 200

How to repeat:
Linux ellex07 4.18.0-32.el8.aarch64 #1 SMP Thu Mar 28 15:54:26 PDT 2019 aarch64 aarch64 aarch64 GNU/Linux

$cat /etc/os-release 
NAME="Oracle Linux Server"
VERSION="8.0"
ID="ol"
VARIANT="Server"
VARIANT_ID="server"
VERSION_ID="8.0"
PLATFORM_ID="platform:el8"
PRETTY_NAME="Oracle Linux Server 8.0"

cmake <path to source> -DMYSQL_MAINTAINER_MODE=1
make mysqldmp

Suggested fix:
Larger 'buf' is needed.

[12 Jul 2019 18:27] Paul DuBois

Posted by developer:
 
Fixed in 8.0.18.

A mysqldump error-message buffer was too small, potentially leading
to message truncation.