Originally reported by Helg Bredow <xx404 AT msn.com> via e-mail.
Steps to reproduce

create empty file.
write 4096 bytes at offset 0.
seek to 4097 bytes from start of the file.
write one byte
Expected result

OK
Actual result

Invalid write in BigBuffer::ChunkWrapper::clearTail:
==5323== Invalid write of size 8
==5323==    at 0x4C32552: memset (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==5323==    by 0x114AFE: BigBuffer::ChunkWrapper::clearTail(unsigned long) (bigBuffer.cpp:151)
==5323==    by 0x114401: BigBuffer::write(char const*, unsigned long, unsigned long) (bigBuffer.cpp:232)
==5323==    by 0x10F980: FileNode::write(char const*, unsigned long, unsigned long) (fileNode.cpp:263)
==5323==    by 0x1119AB: fusezip_write (fuse-zip.cpp:269)
==5323==    by 0x4E4532F: fuse_fs_write_buf (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E454A7: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E4E6ED: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E4A99B: fuse_session_loop (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E42C67: fuse_loop (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x10B216: main (main.cpp:242)
==5323==  Address 0x6581f38 is 24 bytes inside a block of size 4,096 free'd
==5323==    at 0x4C2CDDB: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==5323==    by 0x114894: BigBuffer::ChunkWrapper::~ChunkWrapper() (bigBuffer.cpp:62)
==5323==    by 0x115C28: void std::_Destroy<BigBuffer::ChunkWrapper>(BigBuffer::ChunkWrapper*) (stl_construct.h:93)
==5323==    by 0x115986: void std::_Destroy_aux<false>::__destroy<BigBuffer::ChunkWrapper*>(BigBuffer::ChunkWrapper*, BigBuffer::ChunkWrapper*) (stl_construct.h:103)
==5323==    by 0x1151CB: void std::_Destroy<BigBuffer::ChunkWrapper*>(BigBuffer::ChunkWrapper*, BigBuffer::ChunkWrapper*) (stl_construct.h:126)
==5323==    by 0x114DAE: void std::_Destroy<BigBuffer::ChunkWrapper*, BigBuffer::ChunkWrapper>(BigBuffer::ChunkWrapper*, BigBuffer::ChunkWrapper*, std::allocator<BigBuffer::ChunkWrapper>&) (stl_construct.h:151)
==5323==    by 0x114EFF: std::vector<BigBuffer::ChunkWrapper, std::allocator<BigBuffer::ChunkWrapper> >::_M_erase_at_end(BigBuffer::ChunkWrapper*) (stl_vector.h:1436)
==5323==    by 0x114CEE: std::vector<BigBuffer::ChunkWrapper, std::allocator<BigBuffer::ChunkWrapper> >::resize(unsigned long) (stl_vector.h:679)
==5323==    by 0x1144F9: BigBuffer::truncate(unsigned long) (bigBuffer.cpp:251)
==5323==    by 0x10FB8E: FileNode::truncate(unsigned long) (fileNode.cpp:294)
==5323==    by 0x111A8A: fusezip_truncate (fuse-zip.cpp:299)
==5323==    by 0x4E49539: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==  Block was alloc'd at
==5323==    at 0x4C2BBAF: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==5323==    by 0x1148FB: BigBuffer::ChunkWrapper::ptr(bool) (bigBuffer.cpp:84)
==5323==    by 0x113FAB: BigBuffer::BigBuffer(zip*, unsigned long, unsigned long) (bigBuffer.cpp:176)
==5323==    by 0x10F7EB: FileNode::open() (fileNode.cpp:239)
==5323==    by 0x1116AD: fusezip_open (fuse-zip.cpp:210)
==5323==    by 0x4E44967: fuse_fs_open (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E44A41: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E4EF3B: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E4E5D8: ??? (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E4A99B: fuse_session_loop (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x4E42C67: fuse_loop (in /lib/x86_64-linux-gnu/libfuse.so.2.9.7)
==5323==    by 0x10B216: main (main.cpp:242)
Out of bounds write on sparse file

Steps to reproduce

Expected result

Actual result

Comments (5)
