On Wed, 5 Nov 2014 16:17:20 -0500 Steven Rostedt <rost...@goodmis.org> wrote:
> On Wed, 5 Nov 2014 15:00:07 -0500 > Steven Rostedt <rost...@goodmis.org> wrote: > > > On Wed, 5 Nov 2014 13:41:47 -0500 > > Steven Rostedt <rost...@goodmis.org> wrote: > > > > > > > > > > > + */ > > > > > +int seq_buf_bitmask(struct seq_buf *s, const unsigned long *maskp, > > > > > + int nmaskbits) > > > > > +{ > > > > > + unsigned int len = SEQ_BUF_LEFT(s); > > > > > > > > > > + int ret; > > > > > + > > > > > + WARN_ON(s->size == 0); > > > > > + > > > > > + if (s->len < s->size) { > > > > > + ret = bitmap_scnprintf(s->buffer, len, maskp, > > > > > nmaskbits); > > > > > > > > It writes to the beginning of the buffer. It should be > > > > > > > > ret = bitmap_scnprintf(s->buffer + s->len, len, > > > > maskp, nmaskbits); > > > > > > > > > > Yep thanks. Luckily its only user didn't care. > > > > > > Will fix. > > > > > > > > > > > > + if (s->len + ret < s->size) { > > > > > > > > This will always happen because bitmap_scnprintf() is limited by > > > > SEQ_BUF_LEFT(s) > > > > and it currently returns the remaining size - len - 1. > > > > > > Hmm, that's correct, as bitmap_scnprintf() returns the amount written > > > instead of the amount that it would write like snprintf() would. > > > > > > > > > > > > > > You might want to use "s->size - s->len" instead of SEQ_BUF_LEFT(s). > > > > > > That wont help when we make overflow len > size. > > > > > > Probably should see if ret == the amount of bits required for the > > > bitmask. > > > > Here's the new version: > > > > Take 2: > > int seq_buf_bitmask(struct seq_buf *s, const unsigned long *maskp, > int nmaskbits) > { > unsigned int len = seq_buf_buffer_left(s); Bah, I need to make this: len = s->size - s->len. As this would work for both cases of what a overflowed buffer is. -- Steve > int ret; > > WARN_ON(s->size == 0); > > if (s->len < s->size) { > ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits); > /* > * Note, because bitmap_scnprintf() only returns the > * number of bytes written and not the number that > * would be written, we use the last byte of the buffer > * to let us know if we overflowed. There's a small > * chance that the bitmap could have fit exactly inside > * the buffer, but it's not that critical if that does > * happen. > */ > if (s->len + ret < s->size) { > s->len += ret; > return 0; > } > } > seq_buf_set_overflow(s); > return -1; > } > > -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/