Date: Wed, 21 Oct 2015 20:32:48 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 203944] makefs: Coverity CID 979130: Possibly gone after PR 203938 / CID 975345, 975346 is done Message-ID: <bug-203944-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=203944 Bug ID: 203944 Summary: makefs: Coverity CID 979130: Possibly gone after PR 203938 / CID 975345, 975346 is done Product: Base System Version: 11.0-CURRENT Hardware: Any OS: Any Status: New Severity: Affects Some People Priority: --- Component: bin Assignee: freebsd-bugs@FreeBSD.org Reporter: scdbackup@gmx.net usr.sbin/makefs/cd9660/iso9660_debug.c CID 979131 (#2 of 2): Untrusted value as argument (TAINTED_SCALAR) 4. tainted_data: Passing tainted variable pttemp.length to a tainted sink. 210 debug_dump_to_xml_ptentry(&pttemp, n, mode); CID 979130 (#1 of 1): Untrusted value as argument (TAINTED_SCALAR) 20. tainted_data: Passing tainted variable t2 to a tainted sink. 257 debug_dump_to_xml_path_table(fd, t, t2, 721); --------------- Source analysis: With CID 979131 Coverity first points to: CID 975346: Ignoring number of bytes read (CHECKED_RETURN) 3. tainted_data_argument: Calling function fread taints argument pttemp 205 fread(&pttemp, 1, 8, fd); and next to CID 979131. With CID 979130 Coverity first points to: CID 975345: Ignoring number of bytes read (CHECKED_RETURN) 10. tainted_data_argument: Calling function fread taints argument buf. 238 fread(buf, 1, CD9660_SECTOR_SIZE, fd); Then it complains about further use of buf, of which is not clear that it contains valid data. 12. tainted_data_transitive: Call to function memcpy with tainted argument buf transitively taints primaryVD 245 memcpy(&primaryVD, buf, CD9660_SECTOR_SIZE); 18. tainted_data_transitive: Call to function debug_get_encoded_number with tainted argument primaryVD.path_table_size returns tainted data. 19. var_assign: Assigning: t2 = debug_get_encoded_number, which taints t2. and next to CID 979130. So if error checks make sure that only valid buf content is processed, both chains of tainting should be prevented from starting. --------------- Remedy proposal: In the next Coverity re-run after PR 203938 is solved, check whether tainted parameters in functions debug_dump_to_xml() and debug_dump_to_xml_path_table() are reported again. ------------------------------------------------------------------------ This is for now the last Coverity CID which is about makefs ISO 9660 production. Hopefully none slipped through. There are still some left about FFS production. -- You are receiving this mail because: You are the assignee for the bug.
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