| Message ID | 20181215011923.246179-1-zenczykowski@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | John Linville |
| Headers | show |
| Series | ethtool: zero initialize coalesce struct | expand |
On Fri, Dec 14, 2018 at 05:19:23PM -0800, Maciej Żenczykowski wrote: > From: Maciej Żenczykowski <maze@google.com> > > prior to fetching it from kernel. > > Otherwise we run the risk of very tail portion of it (dmac field) > being left entirely uninitialized, and likely containing some sort > of stale data. The dmac member of struct ethtool_coalesce was removed by commit c0b078ce7e88 ("Revert "ethtool: Add DMA Coalescing support"") because it has never been added in kernel (as that would break compatibility with older ethtool versions). Michal Kubecek
> The dmac member of struct ethtool_coalesce was removed by commit > c0b078ce7e88 ("Revert "ethtool: Add DMA Coalescing support"") because it > has never been added in kernel (as that would break compatibility with > older ethtool versions). Hmm, well, it doesn't hurt to zero init either way...
I handed over ethtool to John Linville some time ago. Ben. On Fri, 2018-12-14 at 17:19 -0800, Maciej Żenczykowski wrote: > From: Maciej Żenczykowski <maze@google.com> > > prior to fetching it from kernel. > > Otherwise we run the risk of very tail portion of it (dmac field) > being left entirely uninitialized, and likely containing some sort > of stale data. > > It seems to likely be some sort of time (a second's counter). > > Tested: > 'ethtool -c eth1' with old kernel now reports 'dmac: 0' where > previously it reported some sort of second counter. > > Signed-off-by: Maciej Żenczykowski <maze@google.com> > --- > ethtool.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/ethtool.c b/ethtool.c > index 2f7e96bb58db..465eeecb9318 100644 > --- a/ethtool.c > +++ b/ethtool.c > @@ -2076,7 +2076,7 @@ static int do_gchannels(struct cmd_context *ctx) > > static int do_gcoalesce(struct cmd_context *ctx) > { > - struct ethtool_coalesce ecoal; > + struct ethtool_coalesce ecoal = {}; > int err; > > if (ctx->argc != 0)
On Fri, Dec 14, 2018 at 05:19:23PM -0800, Maciej Żenczykowski wrote: > From: Maciej Żenczykowski <maze@google.com> > > prior to fetching it from kernel. > > Otherwise we run the risk of very tail portion of it (dmac field) > being left entirely uninitialized, and likely containing some sort > of stale data. > > It seems to likely be some sort of time (a second's counter). > > Tested: > 'ethtool -c eth1' with old kernel now reports 'dmac: 0' where > previously it reported some sort of second counter. > > Signed-off-by: Maciej Żenczykowski <maze@google.com> Queued for next release.
diff --git a/ethtool.c b/ethtool.c index 2f7e96bb58db..465eeecb9318 100644 --- a/ethtool.c +++ b/ethtool.c @@ -2076,7 +2076,7 @@ static int do_gchannels(struct cmd_context *ctx) static int do_gcoalesce(struct cmd_context *ctx) { - struct ethtool_coalesce ecoal; + struct ethtool_coalesce ecoal = {}; int err; if (ctx->argc != 0)