| Message ID | 20220927003953.1942442-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 8f1e1658d365401159f407d78c240262673d1314 |
| Headers | show |
| Series | s390/qeth: Split memcpy() of struct qeth_ipacmd_addr_change flexible array | expand |
On Mon, Sep 26, 2022 at 05:39:53PM -0700, Kees Cook wrote: > To work around a misbehavior of the compiler's ability to see into > composite flexible array structs (as detailed in the coming memcpy() > hardening series[1]), split the memcpy() of the header and the payload > so no false positive run-time overflow warning will be generated. > > [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org/ > > Cc: Alexandra Winter <wintera@linux.ibm.com> > Cc: Wenjia Zhang <wenjia@linux.ibm.com> > Cc: Heiko Carstens <hca@linux.ibm.com> > Cc: Vasily Gorbik <gor@linux.ibm.com> > Cc: Alexander Gordeev <agordeev@linux.ibm.com> > Cc: Christian Borntraeger <borntraeger@linux.ibm.com> > Cc: Sven Schnelle <svens@linux.ibm.com> > Cc: linux-s390@vger.kernel.org > Cc: netdev@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks! -- Gustavo > --- > drivers/s390/net/qeth_l2_main.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c > index 2d4436cbcb47..0ce635b7b472 100644 > --- a/drivers/s390/net/qeth_l2_main.c > +++ b/drivers/s390/net/qeth_l2_main.c > @@ -1530,8 +1530,8 @@ static void qeth_addr_change_event(struct qeth_card *card, > else > INIT_DELAYED_WORK(&data->dwork, qeth_l2_dev2br_worker); > data->card = card; > - memcpy(&data->ac_event, hostevs, > - sizeof(struct qeth_ipacmd_addr_change) + extrasize); > + data->ac_event = *hostevs; > + memcpy(data->ac_event.entry, hostevs->entry, extrasize); > queue_delayed_work(card->event_wq, &data->dwork, 0); > } > > -- > 2.34.1 >
On 27.09.22 03:16, Gustavo A. R. Silva wrote: > On Mon, Sep 26, 2022 at 05:39:53PM -0700, Kees Cook wrote: >> To work around a misbehavior of the compiler's ability to see into >> composite flexible array structs (as detailed in the coming memcpy() >> hardening series[1]), split the memcpy() of the header and the payload >> so no false positive run-time overflow warning will be generated. >> >> [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org/ >> >> Cc: Alexandra Winter <wintera@linux.ibm.com> >> Cc: Wenjia Zhang <wenjia@linux.ibm.com> >> Cc: Heiko Carstens <hca@linux.ibm.com> >> Cc: Vasily Gorbik <gor@linux.ibm.com> >> Cc: Alexander Gordeev <agordeev@linux.ibm.com> >> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> >> Cc: Sven Schnelle <svens@linux.ibm.com> >> Cc: linux-s390@vger.kernel.org >> Cc: netdev@vger.kernel.org >> Signed-off-by: Kees Cook <keescook@chromium.org> > > Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > Thanks! > -- > Gustavo > Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Thank you Alexandra >> --- >> drivers/s390/net/qeth_l2_main.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c >> index 2d4436cbcb47..0ce635b7b472 100644 >> --- a/drivers/s390/net/qeth_l2_main.c >> +++ b/drivers/s390/net/qeth_l2_main.c >> @@ -1530,8 +1530,8 @@ static void qeth_addr_change_event(struct qeth_card *card, >> else >> INIT_DELAYED_WORK(&data->dwork, qeth_l2_dev2br_worker); >> data->card = card; >> - memcpy(&data->ac_event, hostevs, >> - sizeof(struct qeth_ipacmd_addr_change) + extrasize); >> + data->ac_event = *hostevs; >> + memcpy(data->ac_event.entry, hostevs->entry, extrasize); >> queue_delayed_work(card->event_wq, &data->dwork, 0); >> } >> >> -- >> 2.34.1 >>
Hello: This patch was applied to netdev/net-next.git (master) by Jakub Kicinski <kuba@kernel.org>: On Mon, 26 Sep 2022 17:39:53 -0700 you wrote: > To work around a misbehavior of the compiler's ability to see into > composite flexible array structs (as detailed in the coming memcpy() > hardening series[1]), split the memcpy() of the header and the payload > so no false positive run-time overflow warning will be generated. > > [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org/ > > [...] Here is the summary with links: - s390/qeth: Split memcpy() of struct qeth_ipacmd_addr_change flexible array https://git.kernel.org/netdev/net-next/c/8f1e1658d365 You are awesome, thank you!
diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 2d4436cbcb47..0ce635b7b472 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -1530,8 +1530,8 @@ static void qeth_addr_change_event(struct qeth_card *card, else INIT_DELAYED_WORK(&data->dwork, qeth_l2_dev2br_worker); data->card = card; - memcpy(&data->ac_event, hostevs, - sizeof(struct qeth_ipacmd_addr_change) + extrasize); + data->ac_event = *hostevs; + memcpy(data->ac_event.entry, hostevs->entry, extrasize); queue_delayed_work(card->event_wq, &data->dwork, 0); }
To work around a misbehavior of the compiler's ability to see into composite flexible array structs (as detailed in the coming memcpy() hardening series[1]), split the memcpy() of the header and the payload so no false positive run-time overflow warning will be generated. [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org/ Cc: Alexandra Winter <wintera@linux.ibm.com> Cc: Wenjia Zhang <wenjia@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: linux-s390@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/s390/net/qeth_l2_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)