154 lines
2.6 KiB
HTML
154 lines
2.6 KiB
HTML
<HTML
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>Check All System Call Returns</TITLE
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TITLE="Carefully Call Out to Other Resources"
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TITLE="Call Only Interfaces Intended for Programmers"
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>Chapter 8. Carefully Call Out to Other Resources</TD
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>8.5. Check All System Call Returns</H1
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><P
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>Every system call that can return an error condition must have that
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error condition checked.
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One reason is that nearly all system calls require limited system resources,
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and users can often affect resources in a variety of ways.
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Setuid/setgid programs can have limits set on them through calls such as
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setrlimit(3) and nice(2).
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External users of server programs and CGI scripts
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may be able to cause resource exhaustion simply by making a large number
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of simultaneous requests.
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If the error cannot be handled gracefully, then fail safe as discussed earlier.</P
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