Fix fail on malformed certificate table parsing #417
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ideeockus
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src/pe/mod.rs
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| use alloc::borrow::Cow; | ||
| use alloc::string::String; | ||
| use alloc::vec::Vec; | ||
| use core::cmp::max; |
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I'm surprised by these import changes, did the formatter do this?
src/pe/mod.rs
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| @@ -142,7 +140,7 @@ impl<'a> PE<'a> { | |||
| return Err(error::Error::Malformed(format!( | |||
| "Unsupported header magic ({:#x})", | |||
| magic | |||
| ))) | |||
| ))); | |||
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ditto here too, this is also surprising to me
| ) | ||
| .unwrap_or_else(|err| { | ||
| warn!("Cannot parse CertificateTable: {:?}", err); | ||
| Default::default() |
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I can't remember, what is a default certificate directory in this case? is it going to cause other problems further down the line when parsing, or if a user accesses parts of it, will it panic? Does it have offsets into other parts of the PE file that are no longer valid, etc.?
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default is empty table (no certificates), so no wrong offsets there
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So while this is an easy merge, I'm on the fence about whether we should; in general the malformed binary is kind of important to know, and in general, we choose to fail in those cases. However, sometimes we don't, and maybe this is one of those times, but it feels like it's just sort of skipping a malformed thing, and putting a default value in its place, which may be ok, but it also might not be. So I'd like to understand more about:
thanks for your patience! |
OK, that sounds reasonable. What if we add something like |
Hello!
In some PE files Certificate Table can be malformed / contain invalid data. But if we use
ParseOptions::parse_attribute_certificates = true, then whole parsing is failed.I suggest use default
CertificateDirectoryTablein case of error.