btrfsck crashed with SIGSEGV in btrfs_header_nritems()

[Chris Halse Rogers]

Binary package hint: btrfs-tools

A re-do of bug #599186 now that the retracer won't mark it as invalid.

I get this reproducible segfault when fscknig my btrfs partition. The problem in btrfsck code appears to be that btrfs_lookup_extent_info assumes that btrfs_search_slot will fill in a valid path->nodes member of btrfs_path, even when it returns a “missing slot” error value of 1.

Whether this makes sense from an on-disc btrfs format standpoint I have no idea.

ProblemType: Crash
DistroRelease: Ubuntu 10.10
Package: btrfs-tools 0.19+20100601-3
ProcVersionSignature: Ubuntu 2.6.35-6.10-generic 2.6.35-rc3
Uname: Linux 2.6.35-6-generic x86_64
Architecture: amd64
Date: Mon Jul 5 21:41:43 2010
ExecutablePath: /sbin/btrfsck
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Alpha amd64 (20100622)
ProcCmdline: btrfsck /dev/sda2
ProcEnviron:
 LANGUAGE=en_AU:en_GB:en_US:en
 PATH=(custom, no user)
 LANG=en_AU.UTF-8
 SHELL=/bin/zsh
SegvAnalysis:
 Segfault happened at: 0x40f942 <btrfs_print_leaf+24>: mov 0x60(%rbp),%edx
 PC (0x0040f942) ok
 source "0x60(%rbp)" (0x000000c4) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: btrfs-tools
StacktraceTop:
 btrfs_header_nritems (root=0x1948320, l=0x0) at ctree.h:1416
 btrfs_print_leaf (root=0x1948320, l=0x0) at print-tree.c:454
 btrfs_lookup_extent_info (
 run_next_block (root=0x1948320) at btrfsck.c:2510
 check_extents (root=0x1948320) at btrfsck.c:2798
Title: btrfsck crashed with SIGSEGV in btrfs_header_nritems()
UserGroups:

[Apport retracing service (apport)]

StacktraceTop:
 ?? ()
 ?? ()
 ?? ()
 ?? ()
 __libc_start_main (main=<value optimized out>,

[Chris Halse Rogers (raof)]

Ok. Apport failed the retrace, but the initial backtrace has all the symbols resolved and should be good enough for some analysis.

[Surbhi Palande (csurbhi)]

Hi Chris Halse Rogers,

Thanks a lot for your consideration and help :) I have kept a test ppa of btrfs-tools at https://launchpad.net/~csurbhi/+archive/ppa
Can you please let me know if this fixes things for you? I am not able to reproduce the same bug here.

[Launchpad Janitor (janitor)]

[Expired for btrfs-tools (Ubuntu) because there has been no activity for 60 days.]