On (10/30/14 14:20), Weijie Yang wrote: > zram could kunmap_atomic a NULL pointer in a rare situation: > a zram page become a full-zeroed page after a partial write io. > The current code doesn't handle this case and kunmap_atomic a > NULL porinter, which panic the kernel. > > This patch fixes this issue. > > Signed-off-by: Weijie Yang <[email protected]>
thank you, Weijie. Acked-by: Sergey Senozhatsky <[email protected]> -ss > --- > drivers/block/zram/zram_drv.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > index 2ad0b5b..3920ee4 100644 > --- a/drivers/block/zram/zram_drv.c > +++ b/drivers/block/zram/zram_drv.c > @@ -560,7 +560,8 @@ static int zram_bvec_write(struct zram *zram, struct > bio_vec *bvec, u32 index, > } > > if (page_zero_filled(uncmem)) { > - kunmap_atomic(user_mem); > + if (user_mem) > + kunmap_atomic(user_mem); > /* Free memory associated with this sector now. */ > bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); > zram_free_page(zram, index); > -- > 1.7.0.4 > > -- 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/
