• Alexey Dobriyan's avatar
    [ROSE]: Fix rose.ko oops on unload · 891e6a93
    Alexey Dobriyan authored
    Commit a3d38402 aka
    "[AX.25]: Fix unchecked rose_add_loopback_neigh uses"
    transformed rose_loopback_neigh var into statically allocated one.
    However, on unload it will be kfree's which can't work.
    
    Steps to reproduce:
    
    	modprobe rose
    	rmmod rose
    
    BUG: unable to handle kernel NULL pointer dereference at virtual address 00000008
     printing eip:
    c014c664
    *pde = 00000000
    Oops: 0000 [#1]
    PREEMPT DEBUG_PAGEALLOC
    Modules linked in: rose ax25 fan ufs loop usbhid rtc snd_intel8x0 snd_ac97_codec ehci_hcd ac97_bus uhci_hcd thermal usbcore button processor evdev sr_mod cdrom
    CPU:    0
    EIP:    0060:[<c014c664>]    Not tainted VLI
    EFLAGS: 00210086   (2.6.23-rc9 #3)
    EIP is at kfree+0x48/0xa1
    eax: 00000556   ebx: c1734aa0   ecx: f6a5e000   edx: f7082000
    esi: 00000000   edi: f9a55d20   ebp: 00200287   esp: f6a5ef28
    ds: 007b   es: 007b   fs: 0000  gs: 0033  ss: 0068
    Process rmmod (pid: 1823, ti=f6a5e000 task=f7082000 task.ti=f6a5e000)
    Stack: f9a55d20 f9a5200c 00000000 00000000 00000000 f6a5e000 f9a5200c f9a55a00 
           00000000 bf818cf0 f9a51f3f f9a55a00 00000000 c0132c60 65736f72 00000000 
           f69f9630 f69f9528 c014244a f6a4e900 00200246 f7082000 c01025e6 00000000 
    Call Trace:
     [<f9a5200c>] rose_rt_free+0x1d/0x49 [rose]
     [<f9a5200c>] rose_rt_free+0x1d/0x49 [rose]
     [<f9a51f3f>] rose_exit+0x4c/0xd5 [rose]
     [<c0132c60>] sys_delete_module+0x15e/0x186
     [<c014244a>] remove_vma+0x40/0x45
     [<c01025e6>] sysenter_past_esp+0x8f/0x99
     [<c012bacf>] trace_hardirqs_on+0x118/0x13b
     [<c01025b6>] sysenter_past_esp+0x5f/0x99
     =======================
    Code: 05 03 1d 80 db 5b c0 8b 03 25 00 40 02 00 3d 00 40 02 00 75 03 8b 5b 0c 8b 73 10 8b 44 24 18 89 44 24 04 9c 5d fa e8 77 df fd ff <8b> 56 08 89 f8 e8 84 f4 fd ff e8 bd 32 06 00 3b 5c 86 60 75 0f 
    EIP: [<c014c664>] kfree+0x48/0xa1 SS:ESP 0068:f6a5ef28
    Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    891e6a93
rose_route.c 30.4 KB