Re: [PATCH v2] grub-file: fix segmentation fault

[Daniel Kiper]

On Tue, Apr 12, 2016 at 02:24:12PM +0800, Michael Chang wrote:
> In grub_file_open the file handle returned by file filters has no file->name
> set which leads to segmentation fault later referenced by grub_elf_file. This
> patch tries to fix the problem.
>
>  gdb --args ./grub-file --is-x86_64-xen-domu /boot/vmlinux-4.1.12-1-default.gz
>
>  (gdb) bt
>  #0  0x000000000047597e in grub_strlen (s=0x0) at ../grub-core/kern/misc.c:558
>  #1  0x00000000004757e2 in grub_strdup (s=0x0) at ../grub-core/kern/misc.c:463
>  #2  0x0000000000406418 in grub_elf_file (file=0x6dfb50, filename=0x0) at 
> ../grub-core/kern/elf.c:89
>  #3  0x00000000004043b3 in grub_xen_file (file=0x6dfb50) at 
> ../grub-core/loader/i386/xen_file.c:29
>  #4  0x0000000000403930 in grub_cmd_file (ctxt=0x7fffffffe120, argc=1, 
> args=0x6dfa00) at ../grub-core/commands/file.c:425
>  #5  0x000000000047e178 in grub_extcmd_dispatcher (cmd=0x6df730, argc=2, 
> args=0x6ddfb0, script=0x0) at ../grub-core/commands/extcmd.c:54
>  #6  0x000000000047e1d7 in grub_extcmd_dispatch (cmd=0x6df730, argc=2, 
> args=0x6ddfb0) at ../grub-core/commands/extcmd.c:67
>  #7  0x0000000000402945 in main (argc=3, argv=0x7fffffffe2e8) at 
> ../util/grub-file.c:102
>  (gdb) frame 3
>  #3  0x00000000004043b3 in grub_xen_file (file=0x6dfb50) at 
> ../grub-core/loader/i386/xen_file.c:29
>  29        elf = grub_elf_file (file, file->name);
>
> v2: Keep the file->name in file io handle for filters as it would be fetched 
> by
> progress and used modules, according to the review by Andrei Borzenkov.

Vladimir, Andrei, could you take care of it?

Daniel