On Tue, Jul 14, 2015 at 12:23 AM, Horacio Mijail Anton Quiles <[email protected]> wrote: > An hexdump with a buf not aligned to the groupsize causes > non-naturally-aligned memory accesses. This was causing a kernel panic > on the processor BlackFin BF527, when such an unaligned buffer was fed > by the function ubifs_scanned_corruption in fs/ubifs/scan.c . > > To fix this, change accesses to the contents of the buffer so they go > through get_unaligned(). This change should be harmless to unaligned- > access-capable architectures, and any performance hit should be anyway > dwarfed by the snprintf() processing time. > > Signed-off-by: Horacio Mijail Antón Quiles <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> > --- a/lib/hexdump.c > +++ b/lib/hexdump.c > @@ -11,6 +11,7 @@ > @@ -139,7 +140,8 @@ int hex_dump_to_buffer(const void *buf, size_t len, int > rowsize, int groupsize, > for (j = 0; j < ngroups; j++) { > ret = snprintf(linebuf + lx, linebuflen - lx, > "%s%16.16llx", j ? " " : "", > - (unsigned long long)*(ptr8 + j)); > + (unsigned long long) > + get_unaligned(ptr8 + j)); I think the cast to "unsigned long long" dates back to the days u64 was "unsigned long" on some 64-bit architectures. As u64 is now "unsigned long long", it can be removed. Would you mind sending a follow-up patch to just do that? Thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected] In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
