| Message ID | 1459678418-25820-1-git-send-email-lersek@redhat.com |
|---|---|
| State | Accepted |
| Commit | 166a6552a829ab680862331449f11970c085f26d |
| Headers | show |
On 04/04/16 05:45, Subramanian, Sriram (EG Servers Platform SW) wrote: > Thanks for testing that, Laszlo. > > Reviewed-by: Sriram Subramanian <sriram-s@hpe.com> Thanks a lot for the quick review! Since this bug makes OVMF more or less unusable, I pushed the patch (which is also very simple) with your R-b: 166a6552a829. Thanks! Laszlo > -----Original Message----- > From: Laszlo Ersek [mailto:lersek@redhat.com] > Sent: Sunday, April 3, 2016 3:44 PM > To: edk2-devel-01 <edk2-devel@ml01.01.org> > Cc: Siyuan Fu <siyuan.fu@intel.com>; Jiaxin Wu <jiaxin.wu@intel.com>; Ting Ye <ting.ye@intel.com>; Subramanian, Sriram (EG Servers Platform SW) <sriram-s@hpe.com> > Subject: [PATCH] MdeModulePkg: DxeUdpIoLib: fix non-empty payload path in UDP reception > > Commit 1b31acb66c02 ("MdeModulePkg: Check received packet size before use > it.") introduced a chunk of code under the new "Resume" label, in function > UdpIoOnDgramRcvdDpc(). The new code is supposed to run only when the > received packet has zero-length payload, but a "return" statement was > forgotten, and the code is reached on the normal (nonzero-length payload) > path as well, after the packet has been processed (and possibly freed) by > RxToken->CallBack(). This is a logic bug, with the direct symptom being > use-after-free / General Protection Fault. > > Cc: Siyuan Fu <siyuan.fu@intel.com> > Cc: Jiaxin Wu <jiaxin.wu@intel.com> > Cc: Ting Ye <ting.ye@intel.com> > Cc: "Subramanian, Sriram (EG Servers Platform SW)" <sriram-s@hpe.com> > Fixes: 1b31acb66c026f2791c959a4ec9b55c04d583c22 > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Laszlo Ersek <lersek@redhat.com> > --- > MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c b/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c > index 4f7126d3ce56..4861095435e6 100644 > --- a/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c > +++ b/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c > @@ -303,6 +303,7 @@ UdpIoOnDgramRcvdDpc ( > } > > RxToken->CallBack (Netbuf, &EndPoint, EFI_SUCCESS, RxToken->Context); > + return; > > Resume: > if (RxToken->UdpIo->UdpVersion == UDP_IO_UDP4_VERSION) { > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
diff --git a/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c b/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c index 4f7126d3ce56..4861095435e6 100644 --- a/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c +++ b/MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c @@ -303,6 +303,7 @@ UdpIoOnDgramRcvdDpc ( } RxToken->CallBack (Netbuf, &EndPoint, EFI_SUCCESS, RxToken->Context); + return; Resume: if (RxToken->UdpIo->UdpVersion == UDP_IO_UDP4_VERSION) {
Commit 1b31acb66c02 ("MdeModulePkg: Check received packet size before use it.") introduced a chunk of code under the new "Resume" label, in function UdpIoOnDgramRcvdDpc(). The new code is supposed to run only when the received packet has zero-length payload, but a "return" statement was forgotten, and the code is reached on the normal (nonzero-length payload) path as well, after the packet has been processed (and possibly freed) by RxToken->CallBack(). This is a logic bug, with the direct symptom being use-after-free / General Protection Fault. Cc: Siyuan Fu <siyuan.fu@intel.com> Cc: Jiaxin Wu <jiaxin.wu@intel.com> Cc: Ting Ye <ting.ye@intel.com> Cc: "Subramanian, Sriram (EG Servers Platform SW)" <sriram-s@hpe.com> Fixes: 1b31acb66c026f2791c959a4ec9b55c04d583c22 Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> --- MdeModulePkg/Library/DxeUdpIoLib/DxeUdpIoLib.c | 1 + 1 file changed, 1 insertion(+) -- 1.8.3.1 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel