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JUNE 15, 2026
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x86/disasm

x86/disasm: Fix format string without format specifiers.

Fixed a build failure caused by using a format string without format specifiers in the x86 disassembler.

The x86 disassembler code was updated to avoid using format strings without format specifiers, fixing a build failure triggered by the -Werror=format-security compiler flag. The i386_dis_printf calls were updated to include the %s format specifier when printing strings. This resolves PR binutils/34168.

In Details

This commit fixes a format string vulnerability in opcodes/i386-dis.c. The i386_dis_printf function was being called with a format string that lacked format specifiers, triggering a compiler error when -Werror=format-security is enabled. The fix adds the %s specifier to ensure the string is treated as a string literal.

For Context

When printing output, the C standard library's printf function and its variants use a format string to specify how the output should be formatted. Using a string literal as a format string without any format specifiers can lead to security vulnerabilities. This commit fixes such an issue in the x86 disassembler by adding the %s specifier to treat the string as a literal, preventing potential format string exploits and build errors.

Filed Under: x86disassemblersecuritybuild