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Re: [Valgrind-users] Strange warning for invalid read of size 8 in memcpy
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From: Tanmay M. <tan...@ho...> - 2012-07-06 17:59:10
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Thanks John! The libc shared library does not seem to mention any version number. I'm on MacOs 10.6.8 on Intel. How do I get the version of libc?Here's what I get from valgrind -v: ---------------------------------------------------------==57528== Memcheck, a memory error detector==57528== Copyright (C) 2002-2011, and GNU GPL'd, by Julian Seward et al.==57528== Using Valgrind-3.7.0 and LibVEX; rerun with -h for copyright info==57528== Command: ./check==57528== --57528-- Valgrind options:--57528-- -v--57528-- --dsymutil=yes--57528-- Contents of /proc/version:--57528-- can't open /proc/version--57528-- Arch and hwcaps: AMD64, amd64-sse3-cx16--57528-- Page sizes: currently 4096, max supported 4096--57528-- Valgrind library directory: /Users/tan/Tools/valgrind/install_dir/lib/valgrind--57528-- ./check (0x100000000)--57528-- reading syms from primary file (7 4)--57528-- run: /usr/bin/dsymutil "./check"warning: no debug symbols in executable (-arch x86_64)--57528-- dsyms= ./check.dSYM/Contents/Resources/DWARF/check--57528-- /usr/lib/dyld (0x7fff5fc00000)--57528-- reading syms from primary file (6 1186)--57528-- Reading suppressions file: /Users/tan/Tools/valgrind/install_dir/lib/valgrind/default.supp==57528== embedded gdbserver: reading from /var/folders/In/In0K1bIIGmOe2IoRTx-hcE+++TM/-Tmp-//vgdb-pipe-from-vgdb-to-57528-by-tan-on-???==57528== embedded gdbserver: writing to /var/folders/In/In0K1bIIGmOe2IoRTx-hcE+++TM/-Tmp-//vgdb-pipe-to-vgdb-from-57528-by-tan-on-???==57528== embedded gdbserver: shared mem /var/folders/In/In0K1bIIGmOe2IoRTx-hcE+++TM/-Tmp-//vgdb-pipe-shared-mem-vgdb-57528-by-tan-on-???==57528== ==57528== TO CONTROL THIS PROCESS USING vgdb (which you probably==57528== don't want to do, unless you know exactly what you're doing,==57528== or are doing some strange experiment):==57528== /Users/tan/Tools/valgrind/install_dir/lib/valgrind/../../bin/vgdb --pid=57528 ...command...==57528== ==57528== TO DEBUG THIS PROCESS USING GDB: start GDB like this==57528== /path/to/gdb ./check==57528== and then give GDB the following command==57528== target remote | /Users/tan/Tools/valgrind/install_dir/lib/valgrind/../../bin/vgdb --pid=57528==57528== --pid is optional if only one valgrind process is running==57528== --57528-- REDIR: 0x7fff5fc22fb0 (strcmp) redirected to 0x13804cb90 (???)--57528-- REDIR: 0x7fff5fc20693 (arc4random) redirected to 0x13804cc2e (???)--57528-- REDIR: 0x7fff5fc22e90 (strlen) redirected to 0x13804cb5f (???)--57528-- REDIR: 0x7fff5fc22ee0 (strcpy) redirected to 0x13804cbac (???)--57528-- REDIR: 0x7fff5fc2306f (strcat) redirected to 0x13804cb70 (???)--57528-- /Users/tan/Tools/valgrind/install_dir/lib/valgrind/vgpreload_core-amd64-darwin.so (0x100004000)--57528-- reading syms from primary file (3 135)--57528-- dSYM= /Users/tan/Tools/valgrind/install_dir/lib/valgrind/vgpreload_core-amd64-darwin.so.dSYM/Contents/Resources/DWARF/vgpreload_core-amd64-darwin.so--57528-- reading dwarf3 from dsyms file--57528-- /Users/tan/Tools/valgrind/install_dir/lib/valgrind/vgpreload_memcheck-amd64-darwin.so (0x10000f000)--57528-- reading syms from primary file (32 273)--57528-- dSYM= /Users/tan/Tools/valgrind/install_dir/lib/valgrind/vgpreload_memcheck-amd64-darwin.so.dSYM/Contents/Resources/DWARF/vgpreload_memcheck-amd64-darwin.so--57528-- reading dwarf3 from dsyms file--57528-- /usr/lib/libSystem.B.dylib (0x10001d000)--57528-- reading syms from primary file (4606 3793)--57528-- REDIR: 0x10001deb4 (memset) redirected to 0x100010c80 (memset)--57528-- REDIR: 0x10001fc5c (malloc) redirected to 0x1000105f7 (malloc)--57528-- REDIR: 0x100020bf0 (strlen) redirected to 0x100010af0 (strlen)--57528-- REDIR: 0x100020280 (strncmp) redirected to 0x100010be0 (strncmp)sizeof(mvk_lruc_kv_t)=152, 0x1002772f0, 0x100277388, 0x100277420, 0x1002770e0at index 0end at index 0at index 1==57528== Invalid read of size 8==57528== at 0x7FFFFFE00BAC: ???==57528== by 0x100000E4D: __inline_memcpy_chk (in ./check)==57528== by 0x100000DCF: main (in ./check)==57528== Address 0x1002772a8 is 0 bytes after a block of size 456 alloc'd==57528== at 0x100010679: malloc (vg_replace_malloc.c:266)==57528== by 0x100000CC5: main (in ./check)==57528== end at index 1at index 2end at index 2at index 3-------------------------- some more similar printf outputs pruned here --------------------------------at index 26end at index 26==57528== ==57528== HEAP SUMMARY:==57528== in use at exit: 9,200 bytes in 4 blocks==57528== total heap usage: 4 allocs, 0 frees, 9,200 bytes allocated==57528== ==57528== Searching for pointers to 4 not-freed blocks==57528== Checked 415,728 bytes==57528== ==57528== LEAK SUMMARY:==57528== definitely lost: 5,016 bytes in 2 blocks==57528== indirectly lost: 0 bytes in 0 blocks==57528== possibly lost: 0 bytes in 0 blocks==57528== still reachable: 4,096 bytes in 1 blocks==57528== suppressed: 88 bytes in 1 blocks==57528== Rerun with --leak-check=full to see details of leaked memory==57528== ==57528== ERROR SUMMARY: 13 errors from 1 contexts (suppressed: 0 from 0)==57528== ==57528== 13 errors in context 1 of 1:==57528== Invalid read of size 8==57528== at 0x7FFFFFE00BAC: ???==57528== by 0x100000E4D: __inline_memcpy_chk (in ./check)==57528== by 0x100000DCF: main (in ./check)==57528== Address 0x1002772a8 is 0 bytes after a block of size 456 alloc'd==57528== at 0x100010679: malloc (vg_replace_malloc.c:266)==57528== by 0x100000CC5: main (in ./check)==57528== --57528-- --57528-- used_suppression: 1 libSystem-keymgr-leak-at-exit==57528== ==57528== ERROR SUMMARY: 13 errors from 1 contexts (suppressed: 0 from 0) --------------------------------------------------------------------------------- > Date: Fri, 6 Jul 2012 08:16:33 -0700 > From: jr...@bi... > To: val...@li... > Subject: Re: [Valgrind-users] Strange warning for invalid read of size 8 in memcpy > > > I'm getting an invalid read of size 8 warning with the code (check.c) below. > > Everything seems to be fine, and the warning about reading beyond the allocated source pointer comes only when I'm copying the source to a particular index of the destination. > > > > Please copy+paste the exact error message and traceback. The pc matters: > your program, memcheck's interceptor, or un-intercepted libc instructions. > Also, the addresses matter: the low-order 5 bits of each of the source, > destination, and length. > > > My environment: > > - MacOSX Darwin 10.8.0 Darwin Kernel Version 10.8.0 > > - valgrind-3.7.0 > > - gcc version: i686-apple-darwin10-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5666) (dot 3) > > Thank you for reporting those versions! Also, which version of libc are you using? > > Re-run with "valgrind -v ./check". Check the suppressions file > --1658-- Reading suppressions file: /usr/lib64/valgrind/default.supp > to see which mem* reports are being suppressed, and by which version of > the suppressions master file(s). > Pay particular attention to all REDIR which refer to mem* functions: > --1658-- REDIR: 0x363b88e690 (memcpy@@GLIBC_2.14) redirected to 0x4802700 (_vgnU_ifunc_wrapper) > --1658-- REDIR: 0x363b944b40 (__memcpy_ssse3_back) redirected to 0x4a09ff0 (memcpy@@GLIBC_2.14) > > memcheck gives me no complaints when running your check.c on Fedora 17: > Linux host.domain 3.4.3-1.fc17.x86_64 #1 SMP Mon Jun 18 19:53:17 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux > Using Valgrind-3.7.0 > gcc (GCC) 4.7.0 20120507 (Red Hat 4.7.0-5) > glibc-2.15-37.fc17.x86_64 > > -- > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Valgrind-users mailing list > Val...@li... > https://lists.sourceforge.net/lists/listinfo/valgrind-users |
