Re: [hatari-devel] fix null pointer dereference in Dialog_HaltDlg

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 11/08/2018 à 15:13, Steven Noonan a écrit :
> Or more accurately, in SDLGui_CenterDlg, but Dialog_HaltDlg is 
> effectively responsible for the dereference:
>
> Thread 1 "hatari" received signal SIGSEGV, Segmentation fault.
> 0x0000555555fcf152 in SDLGui_CenterDlg (dlg=dlg@entry=0x5555564d2e80 
> <haltdlg>) at ../src/gui-sdl/sdlgui.c:224
> 224             dlg[0].x = (pSdlGuiScrn->w/sdlgui_fontwidth-dlg[0].w)/2;
> (gdb) bt
> #0  0x0000555555fcf152 in SDLGui_CenterDlg (dlg=dlg@entry=0x5555564d2e80 
> <haltdlg>) at ../src/gui-sdl/sdlgui.c:224
> #1  0x0000555555fccdae in Dialog_HaltDlg () at ../src/gui-sdl/dlgHalt.c:75
> #2  0x00005555558ebc9d in cpu_halt (id=2) at ../src/cpu/newcpu.c:6273
> #3  Exception_ce000 (nr=2) at ../src/cpu/newcpu.c:3258
> #4  ExceptionX (nr=nr@entry=2, address=address@entry=4294967295) at 
> ../src/cpu/newcpu.c:4088
> #5  0x00005555558ecf69 in Exception (nr=nr@entry=2) at 
> ../src/cpu/newcpu.c:4125
> #6  0x00005555558ed8c9 in bus_error () at ../src/cpu/newcpu.c:4135
> #7  0x00005555558ef000 in m68k_run_1_ce () at ../src/cpu/newcpu.c:5808
> #8  0x00005555558ee143 in m68k_go (may_quit=may_quit@entry=1) at 
> ../src/cpu/newcpu.c:7640
> #9  0x000055555589d814 in M68000_Start () at ../src/m68000.c:298
> #10 0x000055555589eb19 in main (argc=1, argv=<optimized out>) at 
> ../src/main.c:946
> (gdb) p pSdlGuiScrn
> $1 = (SDL_Surface *) 0x0
>
> I ran into this when trying to use the TOS 2.07 Sparrow ROM with a 
> MegaSTE configuration on the current Mercurial tree.
>
> Attached patch ensures we do SDLGui_SetScreen before SDLGui_CenterDlg in 
> Dialog_HaltDlg, which makes the dialog appear as intended.[1]
>
> That said, any news on getting TOS 2.07 running? Just curious...
>
> - Steven
>
> [1] https://i.imgur.com/mF2M8Jl.png


Hi

thanks for the patch and for taking the time to track down this issue.
Patch was pushed to main sources.

As for Sparrow TOS 2.07, I can't say myself as I didn't try it so far.

Nicolas