ZIP: Fix NULL-dereference for OOXML scans#1552
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I accidentally introduced a NULL-dereference bug when scanning any OOXML file in Cisco-Talos#1548 I overlooked the test failure out of haste. 😔 The NULL-dereference happens because the `unzip_search()` feature allowed searching some other file than the one that is currently being scanned, which you would do by setting `ctx` to NULL and setting an `fmap` parameter instead. In practice, the current layer's `fmap` from the `ctx` was always passed in. This fix makes it so the `unzip_search()` and related functions only take the `ctx` parameter and do not have and `fmap` or `fsize` field (Note: the `fsize` was never needed, because `fmap->len` take care of that). CLAM-2837
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TheRaynMan
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Thanks for the unzip.c edits.
jhumlick
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I accidentally introduced a NULL-dereference bug when scanning any OOXML file in Cisco-Talos#1548 I overlooked the test failure out of haste. 😔 The NULL-dereference happens because the `unzip_search()` feature allowed searching some other file than the one that is currently being scanned, which you would do by setting `ctx` to NULL and setting an `fmap` parameter instead. In practice, the current layer's `fmap` from the `ctx` was always passed in. This fix makes it so the `unzip_search()` and related functions only take the `ctx` parameter and do not have and `fmap` or `fsize` field (Note: the `fsize` was never needed, because `fmap->len` take care of that). CLAM-2837
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I accidentally introduced a NULL-dereference bug when scanning any OOXML file in #1548
I overlooked the test failure out of haste. 😔
The NULL-dereference happens because the
unzip_search()feature allowed searching some other file than the one that is currently being scanned, which you would do by settingctxto NULL and setting anfmapparameter instead.In practice, the current layer's
fmapfrom thectxwas always passed in.This fix makes it so the
unzip_search()and related functions only take thectxparameter and do not have andfmaporfsizefield (Note: thefsizewas never needed, becausefmap->lentake care of that).CLAM-2837