New: Oops when renaming interfaces added to a bridge

http://bugzilla.kernel.org/show_bug.cgi?id=12743

           Summary: Oops when renaming interfaces added to a bridge
           Product: Networking
           Version: 2.5
     KernelVersion: 2.6.27.18
          Platform: All
        OS/Version: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: Other
        AssignedTo: [email protected]
        ReportedBy: [email protected]

Distribution: custom
Hardware Environment: ARM PXA320
[reproduced on Fedora 10 with 2.6.27.15-170.2.24.fc10.x86_64 too]

Problem Description:

When renaming an interface which was added to a bridge, its name won't be changed in the bridge setup. Adding another interface which was created later with the original name, kernel oopses

A 'find /sys -name dummy*' between step 4 and 5 reports

/sys/devices/virtual/net/br0/brif/dummy0
/sys/devices/virtual/net/dummy100
/sys/bus/i2c/drivers/dummy
/sys/class/net/dummy100

Although it is only a WARNING, system goes havoc because whole networking stack seems to be unusable then.

Steps to reproduce:

1. brctl addbr br0

2. modprobe -o d0 dummy
3. brctl addif br0 dummy0

4. ifrename -i dummy0 -n dummy100

5. modprobe -o d1 dummy
6. brctl addif br0 dummy0

device dummy0 entered promiscuous mode

------------[ cut here ]------------
WARNING: at fs/sysfs/dir.c:463 sysfs_add_one+0x34/0x48()

....

Quoted 4 lines

When renaming an interface which was added to a bridge, its name won't be changed in the bridge setup. Adding another interface which was created later with the original name, kernel oopses