Created attachment 79774 [details]
A bad PDF file

When pdfinfo receives a corrupt file that is piped in via stdin it hangs with 100% CPU usage.

Example Usage:

cat damaged.pdf | pdfinfo -

Output:

Syntax Warning: May not be a PDF file (continuing anyway)

Expected outcome:

The program should terminate after determining that the file is corrupt

Actual outcome:

After outputting the one error message it never terminates and sits there using 100% of the CPU.

It is worth noting that when pdfinfo is invoked with the exact same file via:

pdfinfo damaged.pdf

instead of piping the corrupt PDF in via stdin then this problem does not happen and the output is:

Syntax Warning: May not be a PDF file (continuing anyway)
Syntax Error: Couldn't find trailer dictionary
Syntax Error: Couldn't read xref table

Then the process terminates as expected.

I have attached the bad file that I am using to test with and recreate this issue.