See also https://bugzilla.kernel.org/show_bug.cgi?id=97171
Running btrfs-progs v3.19.1 The btrfs-image attached to this bug causes the btrfs-userland tool to use uninitialized memory and ultimately overwrite what seems to be arbitrary memory locations, dying in the process. Reproduced on x86-64 and i686. The kernel seems to be less affected and fails to mount the image. If /usr/sbin/btrfs is not setuid (which it probably never is), things should be safe. I didn't investigate further though. gdb output: GNU gdb (GDB) Fedora 7.8.2-38.fc21 [... lots of other errors...] Ignoring transid failure root 5 inode 260 errors 1000, some csum missing unresolved ref dir 256 index 7 namelen 5 name b.bin filetype 1 errors 2, no dir index unresolved ref dir 256 index 7 namelen 5 name b.fin filetype 1 errors 5, no dir item, no inode ref root 5 inode 261 errors 200, dir isize wrong Program received signal SIGSEGV, Segmentation fault. 0x000000000089bb70 in ?? () (gdb) bt #0 0x000000000089bb70 in ?? () #1 0x00007fffffffdb50 in ?? () #2 0x0000000000894b20 in ?? () #3 0x00000032629b88e0 in _IO_2_1_stdout_ () from /lib64/libc.so.6 #4 0x000000000088c010 in ?? () #5 0x0000000000000000 in ?? () valgrind output: [...lots of errors...] ==12638== Conditional jump or move depends on uninitialised value(s) ==12638== at 0x436E77: check_block.part.14 (ctree.c:548) ==12638== by 0x438954: UnknownInlinedFun (kerncompat.h:91) ==12638== by 0x438954: btrfs_search_slot (ctree.c:1120) ==12638== by 0x40DD1F: count_csum_range (cmds-check.c:1419) ==12638== by 0x40DD1F: process_file_extent (cmds-check.c:1551) ==12638== by 0x40DD1F: process_one_leaf (cmds-check.c:1617) ==12638== by 0x40DD1F: walk_down_tree (cmds-check.c:1742) ==12638== by 0x40DD1F: check_fs_root (cmds-check.c:3380) ==12638== by 0x40DD1F: check_fs_roots.isra.51 (cmds-check.c:3516) ==12638== by 0x4C64B0F: ??? ==12638== by 0x4C30A2F: ??? ==12638== by 0x4C468CF: ??? ==12638== by 0x32629B88DF: ??? (in /usr/lib64/libc-2.20.so) ==12638== by 0x4C3657F: ??? ==12638== [...lots of warnings...] ==12638== ==12638== Use of uninitialised value of size 8 ==12638== at 0x4A0B3A0: memcpy@@GLIBC_2.14 (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==12638== by 0x436E99: UnknownInlinedFun (ctree.h:1613) ==12638== by 0x436E99: check_block.part.14 (ctree.c:550) ==12638== by 0x438954: UnknownInlinedFun (kerncompat.h:91) ==12638== by 0x438954: btrfs_search_slot (ctree.c:1120) ==12638== by 0x40DD1F: count_csum_range (cmds-check.c:1419) ==12638== by 0x40DD1F: process_file_extent (cmds-check.c:1551) ==12638== by 0x40DD1F: process_one_leaf (cmds-check.c:1617) ==12638== by 0x40DD1F: walk_down_tree (cmds-check.c:1742) ==12638== by 0x40DD1F: check_fs_root (cmds-check.c:3380) ==12638== by 0x40DD1F: check_fs_roots.isra.51 (cmds-check.c:3516) ==12638== by 0x4C64B0F: ??? ==12638== by 0x4C30A2F: ??? ==12638== by 0x4C468CF: ??? ==12638== by 0x32629B88DF: ??? (in /usr/lib64/libc-2.20.so) ==12638== by 0x4C3657F: ??? ==12638== ==12638== Invalid read of size 1 ==12638== at 0x4A0B3A0: memcpy@@GLIBC_2.14 (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==12638== by 0x436E99: UnknownInlinedFun (ctree.h:1613) ==12638== by 0x436E99: check_block.part.14 (ctree.c:550) ==12638== by 0x438954: UnknownInlinedFun (kerncompat.h:91) ==12638== by 0x438954: btrfs_search_slot (ctree.c:1120) ==12638== by 0x40DD1F: count_csum_range (cmds-check.c:1419) ==12638== by 0x40DD1F: process_file_extent (cmds-check.c:1551) ==12638== by 0x40DD1F: process_one_leaf (cmds-check.c:1617) ==12638== by 0x40DD1F: walk_down_tree (cmds-check.c:1742) ==12638== by 0x40DD1F: check_fs_root (cmds-check.c:3380) ==12638== by 0x40DD1F: check_fs_roots.isra.51 (cmds-check.c:3516) ==12638== by 0x4C64B0F: ??? ==12638== by 0x4C30A2F: ??? ==12638== by 0x4C468CF: ??? ==12638== by 0x32629B88DF: ??? (in /usr/lib64/libc-2.20.so) ==12638== by 0x4C3657F: ??? ==12638== Address 0xa25c9de9 is not stack'd, malloc'd or (recently) free'd ==12638== ==12638== ==12638== Process terminating with default action of signal 11 (SIGSEGV) ==12638== Access not within mapped region at address 0xA25C9DE9 ==12638== at 0x4A0B3A0: memcpy@@GLIBC_2.14 (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so) ==12638== by 0x436E99: UnknownInlinedFun (ctree.h:1613) ==12638== by 0x436E99: check_block.part.14 (ctree.c:550) ==12638== by 0x438954: UnknownInlinedFun (kerncompat.h:91) ==12638== by 0x438954: btrfs_search_slot (ctree.c:1120) ==12638== by 0x40DD1F: count_csum_range (cmds-check.c:1419) ==12638== by 0x40DD1F: process_file_extent (cmds-check.c:1551) ==12638== by 0x40DD1F: process_one_leaf (cmds-check.c:1617) ==12638== by 0x40DD1F: walk_down_tree (cmds-check.c:1742) ==12638== by 0x40DD1F: check_fs_root (cmds-check.c:3380) ==12638== by 0x40DD1F: check_fs_roots.isra.51 (cmds-check.c:3516) ==12638== by 0x4C64B0F: ??? ==12638== by 0x4C30A2F: ??? ==12638== by 0x4C468CF: ??? ==12638== by 0x32629B88DF: ??? (in /usr/lib64/libc-2.20.so) ==12638== by 0x4C3657F: ??? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
