On Wed, Sep 30, 2026 at 04:52:38PM -0700, Kees Cook wrote: > flags_show() build their output with a seq_buf and return seq_buf_used(), > which may include the trailing NUL byte when the seq_buf has > overflowed. Use seq_buf_strlen() instead. > > The flag names are far shorter than the PAGE_SIZE buffer sysfs > provides, so this cannot overflow today. > > Build tested ARCH=x86_64 with GCC 16.2.0, built out of tree with > make M=tools/testing/nvdimm: > tools/testing/nvdimm/test/ndtest.o > > Assisted-by: LLM > Reviewed-by: Andy Shevchenko <[email protected]> > Reviewed-by: Dave Jiang <[email protected]> > Signed-off-by: Kees Cook <[email protected]>
Hi Kees, Should I include this one in a 7.4 PR for nvdimm or is someone else merging the entire series? -- Alison > --- > tools/testing/nvdimm/test/ndtest.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/testing/nvdimm/test/ndtest.c > b/tools/testing/nvdimm/test/ndtest.c > index 2051ad5d4882..f097f2992966 100644 > --- a/tools/testing/nvdimm/test/ndtest.c > +++ b/tools/testing/nvdimm/test/ndtest.c > @@ -693,7 +693,7 @@ static ssize_t flags_show(struct device *dev, > if (seq_buf_used(&s)) > seq_buf_printf(&s, "\n"); > > - return seq_buf_used(&s); > + return seq_buf_strlen(&s); > } > static DEVICE_ATTR_RO(flags); > > -- > 2.34.1 >
