[HDFS-9268] fuse_dfs chown crashes when uid is passed as -1

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Target Version/s: 2.8.0
• Assignee: Colin McCabe
• Reporter: Wei-Chiu Chuang
• Created: 20/Oct/15 14:21
• Updated: 02/Oct/19 17:14
• Resolved: 26/Oct/15 20:35

Description

JVM crashes when users attempt to use vi to update a file on fuse file system with insufficient permission. (I use CDH's hadoop-fuse-dfs wrapper script to generate the bug, but the same bug is reproducible in trunk)

The root cause is a segfault in a dfs-fuse method

To reproduce it do as follows:
mkdir /mnt/fuse
chmod 777 /mnt/fuse
ulimit -c unlimited # to enable coredump
hadoop-fuse-dfs -odebug hdfs://localhost:9000/fuse /mnt/fuse
touch /mnt/fuse/y
chmod 600 /mnt/fuse/y
vim /mnt/fuse/y
(in vim, :w to save the file)

#

1. A fatal error has been detected by the Java Runtime Environment:
   #
2. SIGSEGV (0xb) at pc=0x0000003b82f27ad6, pid=26606, tid=140079005689600
   #
3. JRE version: Java(TM) SE Runtime Environment (7.0_79-b15) (build 1.7.0_79-b15)
4. Java VM: Java HotSpot(TM) 64-Bit Server VM (24.79-b02 mixed mode linux-amd64 compressed oops)
5. Problematic frame:
6. C [libc.so.6+0x127ad6] __tls_get_addr@@GLIBC_2.3+0x127ad6
   #
7. Core dump written. Default location: /home/weichiu/core or core.26606
   #
8. An error report file with more information is saved as:
9. /home/weichiu/hs_err_pid26606.log
   #
10. If you would like to submit a bug report, please visit:
11. http://bugreport.java.com/bugreport/crash.jsp
12. The crash happened outside the Java Virtual Machine in native code.
13. See problematic frame for where to report the bug.
    #
    /usr/bin/hadoop-fuse-dfs: line 29: 26606 Aborted (core dumped) env CLASSPATH="${CLASSPATH}" ${HADOOP_HOME}/bin/fuse_dfs $@

===========
The coredump shows the segfault comes from
(gdb) bt
#0 0x0000003b82e328e5 in raise () from /lib64/libc.so.6
#1 0x0000003b82e340c5 in abort () from /lib64/libc.so.6
#2 0x00007f66fc924d75 in os::abort(bool) () from /etc/alternatives/jre/jre/lib/amd64/server/libjvm.so
#3 0x00007f66fcaa76d7 in VMError::report_and_die() () from /etc/alternatives/jre/jre/lib/amd64/server/libjvm.so
#4 0x00007f66fc929c8f in JVM_handle_linux_signal () from /etc/alternatives/jre/jre/lib/amd64/server/libjvm.so
#5 <signal handler called>
#6 0x0000003b82f27ad6 in __strcmp_sse42 () from /lib64/libc.so.6
#7 0x00000000004039a0 in hdfsConnTree_RB_FIND ()
#8 0x0000000000403e8f in fuseConnect ()
#9 0x00000000004046db in dfs_chown ()
#10 0x00007f66fcf8f6d2 in ?? () from /lib64/libfuse.so.2
#11 0x00007f66fcf940d1 in ?? () from /lib64/libfuse.so.2
#12 0x00007f66fcf910ef in ?? () from /lib64/libfuse.so.2
#13 0x0000003b83207851 in start_thread () from /lib64/libpthread.so.0
#14 0x0000003b82ee894d in clone () from /lib64/libc.so.6

Issue Links

• is related to: HDFS-9307 fuseConnect should be private to fuse_connect.c