On Mon, Nov 21, 2016 at 12:46:48AM -0500, Oleg Drokin wrote: > From: Jian Yu <jian.yu@xxxxxxxxx> > > This patch removes the usage of MAX_STRING_SIZE from > copy_from_user() and just copies enough bytes to cover > count passed in. > > Signed-off-by: Jian Yu <jian.yu@xxxxxxxxx> > Reviewed-on: http://review.whamcloud.com/23462 > Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8774 > Reviewed-by: John L. Hammond <john.hammond@xxxxxxxxx> > Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx> > --- > drivers/staging/lustre/lustre/obdclass/lprocfs_status.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c > index 8a2f02f3..db49992 100644 > --- a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c > +++ b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c > @@ -400,10 +400,17 @@ int lprocfs_wr_uint(struct file *file, const char __user *buffer, > char dummy[MAX_STRING_SIZE + 1], *end; > unsigned long tmp; > > - dummy[MAX_STRING_SIZE] = '\0'; > - if (copy_from_user(dummy, buffer, MAX_STRING_SIZE)) > + if (count >= sizeof(dummy)) > + return -EINVAL; > + > + if (count == 0) > + return 0; > + > + if (copy_from_user(dummy, buffer, count)) > return -EFAULT; > > + dummy[count] = '\0'; > + You do know about simple_read_from_buffer(), right? I suggest using those simple_* functions where ever you are touching user buffers, like this code. thanks, greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
