Fix for issue #1942 #1944
Fix for issue #1942 #1944
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| { | ||
| if (this.Data[i++] != 28) | ||
| bool isValidTagMarker = this.Data[offset++] == IptcTagMarkerByte; | ||
| byte recordType = this.Data[offset++]; |
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I see recordType is unused but I'm struggling to correlate this with the spec. Got any pointers.
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section 1.5 iii:
Octet 2 is the binary representation of the record number. Note that the
envelope record number is always 1, and that the application records are
numbered 2 through 6, the pre-object descriptor record is 7, the object record
is 8, and the post-object descriptor record is 9.
I was not sure what to do with this info. Maybe it would be wise to consider the value invalid if its not in the range of 1 to 9.
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Maybe it would be wise to consider the value invalid if its not in the range of 1 to 9.
Probably wise.
| @@ -242,7 +246,7 @@ public void UpdateData() | |||
| int i = 0; | |||
| foreach (IptcValue value in this.Values) | |||
| { | |||
| this.Data[i++] = 28; | |||
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I wonder whether we should add a little ascii table just indicating what the dataset tags look like?
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| var iptcData = new byte[count]; | ||
| if ((count > 0) && (i + count <= this.Data.Length)) | ||
| if (isValidTagMarker && byteCount > 0 && (offset + byteCount <= this.Data.Length)) |
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| if (isValidTagMarker && byteCount > 0 && (offset + byteCount <= this.Data.Length)) | |
| if (isValidTagMarker && byteCount > 0 && (offset <= this.Data.Length - byteCount)) |
To prevent potential overflow. I see that this won't happen in practice, but I got conditioned to be paranoid about these cases (to be safe against malicious code, etc.).
Co-authored-by: Günther Foidl <gue@korporal.at>
Change condition to (offset <= this.Data.Length - byteCount)
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Lovely stuff @brianpopow thanks for working on this.
Also thanks @gfoidl for the reviews.
Prerequisites
Description
The real cause of issue #1942 is, the provided testimage seems to have a invalid IPTC profile. The second IPTC value does not start with the expected 0x1c tag marker, its 0 instead.
This PR will skips this tag and ignores IPCT's Extended DataSet feature tags.