On Wed, Sep 30, 2026 at 04:52:36PM -0700, Kees Cook wrote: > Several strlcat() call sites being converted to seq_buf need behavior > seq_buf doesn't currently provide. The normal seq_buf_init() always > sets the new buffer size to 0 via seq_buf_clear(). Code migrating from > strlcat(buf, ...), which appends to whatever buf already contains, > can't use seq_buf_init() without discarding that existing content. Add > seq_buf_init_append(), which preserves the existing contents and positions > the seq_buf to append after it. Add KUnit tests for behavior coverage. > > Tests passed under qemu on ARCH=x86_64 with GCC 16.2.0 and CONFIG_KASAN=y, > and on big-endian ARCH=s390 with GCC s390x-linux-gnu 16.1.0.
Yep, makes sense! Reviewed-by: Andy Shevchenko <[email protected]> But one Q below. ... > +static inline void > +seq_buf_init_append(struct seq_buf *s, char *buf, unsigned int size) > +{ > + s->buffer = buf; > + s->size = size; > + s->len = strnlen(buf, size); Hmm... And if this becomes a size? Shouldn't we set the overflow immediately if the existing buffer contains a garbage or has non-NUL-terminated content? > +} -- With Best Regards, Andy Shevchenko
