| Message ID | Y4nMQuEtuVO+rlQy@kili (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e8b4fc13900b8e8be48debffd0dfd391772501f7 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] net: mvneta: Prevent out of bounds read in mvneta_config_rss() | expand |
On Fri, Dec 02, 2022 at 12:58:26PM +0300, Dan Carpenter wrote: > The pp->indir[0] value comes from the user. It is passed to: > > if (cpu_online(pp->rxq_def)) > > inside the mvneta_percpu_elect() function. It needs bounds checkeding > to ensure that it is not beyond the end of the cpu bitmap. > > Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect") > Signed-off-by: Dan Carpenter <error27@gmail.com> > --- > drivers/net/ethernet/marvell/mvneta.c | 3 +++ > 1 file changed, 3 insertions(+) I would expect that ethtool_copy_validate_indir() will prevent this. Thanks > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index c2cb98d24f5c..5abc7c3e399e 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -4927,6 +4927,9 @@ static int mvneta_config_rss(struct mvneta_port *pp) > napi_disable(&pp->napi); > } > > + if (pp->indir[0] >= nr_cpu_ids) > + return -EINVAL; > + > pp->rxq_def = pp->indir[0]; > > /* Update unicast mapping */ > -- > 2.35.1 >
On Sun, Dec 04, 2022 at 02:47:13PM +0200, Leon Romanovsky wrote: > On Fri, Dec 02, 2022 at 12:58:26PM +0300, Dan Carpenter wrote: > > The pp->indir[0] value comes from the user. It is passed to: > > > > if (cpu_online(pp->rxq_def)) > > > > inside the mvneta_percpu_elect() function. It needs bounds checkeding > > to ensure that it is not beyond the end of the cpu bitmap. > > > > Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect") > > Signed-off-by: Dan Carpenter <error27@gmail.com> > > --- > > drivers/net/ethernet/marvell/mvneta.c | 3 +++ > > 1 file changed, 3 insertions(+) > > I would expect that ethtool_copy_validate_indir() will prevent this. > Huh... Sort of, but in the strictest sense, no. mvneta_ethtool_get_rxnfc() sets the cap at 8 by default or an unvalidated module parameter. regards, dan carpenter
Hello: This patch was applied to netdev/net.git (master) by David S. Miller <davem@davemloft.net>: On Fri, 2 Dec 2022 12:58:26 +0300 you wrote: > The pp->indir[0] value comes from the user. It is passed to: > > if (cpu_online(pp->rxq_def)) > > inside the mvneta_percpu_elect() function. It needs bounds checkeding > to ensure that it is not beyond the end of the cpu bitmap. > > [...] Here is the summary with links: - [net] net: mvneta: Prevent out of bounds read in mvneta_config_rss() https://git.kernel.org/netdev/net/c/e8b4fc13900b You are awesome, thank you!
On Mon, Dec 05, 2022 at 12:03:46PM +0300, Dan Carpenter wrote: > On Sun, Dec 04, 2022 at 02:47:13PM +0200, Leon Romanovsky wrote: > > On Fri, Dec 02, 2022 at 12:58:26PM +0300, Dan Carpenter wrote: > > > The pp->indir[0] value comes from the user. It is passed to: > > > > > > if (cpu_online(pp->rxq_def)) > > > > > > inside the mvneta_percpu_elect() function. It needs bounds checkeding > > > to ensure that it is not beyond the end of the cpu bitmap. > > > > > > Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect") > > > Signed-off-by: Dan Carpenter <error27@gmail.com> > > > --- > > > drivers/net/ethernet/marvell/mvneta.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > I would expect that ethtool_copy_validate_indir() will prevent this. > > > > Huh... Sort of, but in the strictest sense, no. mvneta_ethtool_get_rxnfc() > sets the cap at 8 by default or an unvalidated module parameter. And is this solely mvnet issue? Do other drivers safe for this input? Thanks > > regards, > dan carpenter >
On Mon, Dec 05, 2022 at 07:44:12PM +0200, Leon Romanovsky wrote: > On Mon, Dec 05, 2022 at 12:03:46PM +0300, Dan Carpenter wrote: > > On Sun, Dec 04, 2022 at 02:47:13PM +0200, Leon Romanovsky wrote: > > > On Fri, Dec 02, 2022 at 12:58:26PM +0300, Dan Carpenter wrote: > > > > The pp->indir[0] value comes from the user. It is passed to: > > > > > > > > if (cpu_online(pp->rxq_def)) > > > > > > > > inside the mvneta_percpu_elect() function. It needs bounds checkeding > > > > to ensure that it is not beyond the end of the cpu bitmap. > > > > > > > > Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect") > > > > Signed-off-by: Dan Carpenter <error27@gmail.com> > > > > --- > > > > drivers/net/ethernet/marvell/mvneta.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > I would expect that ethtool_copy_validate_indir() will prevent this. > > > > > > > Huh... Sort of, but in the strictest sense, no. mvneta_ethtool_get_rxnfc() > > sets the cap at 8 by default or an unvalidated module parameter. > > And is this solely mvnet issue? Do other drivers safe for this input? > I believe so, yes. However thinking about it now maybe a better fix would be to go back to the original way of using pp->rxq_def % nr_cpu_ids. (Originally it used num_online_cpus() instead of nr_cpu_ids but I think nr_cpu_ids is correct). I will send this patch tomorrow. In this code, if you hit the out of bounds then you kind of deserve it, but there are probably a lot of people who probably have fewer than 8 cores and in that case the bug results in a WARN(). regards, dan carpenter
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index c2cb98d24f5c..5abc7c3e399e 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -4927,6 +4927,9 @@ static int mvneta_config_rss(struct mvneta_port *pp) napi_disable(&pp->napi); } + if (pp->indir[0] >= nr_cpu_ids) + return -EINVAL; + pp->rxq_def = pp->indir[0]; /* Update unicast mapping */
The pp->indir[0] value comes from the user. It is passed to: if (cpu_online(pp->rxq_def)) inside the mvneta_percpu_elect() function. It needs bounds checkeding to ensure that it is not beyond the end of the cpu bitmap. Fixes: cad5d847a093 ("net: mvneta: Fix the CPU choice in mvneta_percpu_elect") Signed-off-by: Dan Carpenter <error27@gmail.com> --- drivers/net/ethernet/marvell/mvneta.c | 3 +++ 1 file changed, 3 insertions(+)