On Thu, Feb 01, 2024 at 12:45:43PM +0100, David Marchand wrote:
> On Tue, Aug 8, 2023 at 8:35 PM Bruce Richardson
> <bruce.richard...@intel.com> wrote:
> >
> > On Tue, Aug 08, 2023 at 10:59:37AM -0700, Tyler Retzlaff wrote:
> > > On Tue, Aug 08, 2023 at 10:24:41AM +0800, lihuisong (C) wrote:
> > > >
> > > > 在 2023/8/3 5:21, Tyler Retzlaff 写道:
> > > > >strlcpy returns type size_t when directly assigning to
> > > > >struct rte_tel_data data_len field it may be truncated leading to
> > > > >compromised length check that follows
> > > > >
> > > > >Since the limit in the check is < UINT_MAX the value returned is
> > > > >safe to be cast to unsigned int (which may be narrower than size_t)
> > > > >but only after being checked against RTE_TEL_MAX_SINGLE_STRING_LEN
> > > > >
> > > > >Signed-off-by: Tyler Retzlaff <roret...@linux.microsoft.com>
> > > > >---
> > > > > lib/telemetry/telemetry_data.c | 5 +++--
> > > > > 1 file changed, 3 insertions(+), 2 deletions(-)
> > > > >
> > > > >diff --git a/lib/telemetry/telemetry_data.c
> > > > >b/lib/telemetry/telemetry_data.c
> > > > >index 3b1a240..52307cb 100644
> > > > >--- a/lib/telemetry/telemetry_data.c
> > > > >+++ b/lib/telemetry/telemetry_data.c
> > > > >@@ -41,12 +41,13 @@
> > > > > int
> > > > > rte_tel_data_string(struct rte_tel_data *d, const char *str)
> > > > > {
> > > > >+ const size_t len = strlcpy(d->data.str, str, sizeof(d->data.str));
> > > > sizeof(d->data.str) is equal to RTE_TEL_MAX_SINGLE_STRING_LEN(8192).
> > > > So It seems that this truncation probably will not happen.
> > >
> > > agreed, regardless the data type choices permit a size that exceeds the
> > > range of the narrower type and the assignment results in a warning being
> > > generated on some targets. that's why the truncating cast is safe to
> > > add.
> > >
> > > none of this would be necessary if data_len had been appropriately typed
> > > as size_t. Bruce should we be changing the type instead since we are in
> > > 23.11 merge window...?
> > >
> > I'm fine either way, to be honest.
>
> Can we conclude?
> struct rte_tel_data seems internal (at least opaque from an
> application pov), so I suppose the option of changing data_len to
> size_t is still on the table.
>
> And we are missing a Fixes: tag too.
there is actually a general pattern of this problem across dpdk tree and
this fixes one instance.
i've marked the patch as rejected for now and hope to come back with a
more comprehensive series after msvc work is merged.
ty
>
> Thanks.
>
> --
> David Marchand
