On Sun, Jan 19, 2020 at 02:43:27PM +0100, gregkh@linuxfoundation.org wrote:
The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 42ec15ceaea74b5f7a621fc6686cbf69ca66c4cf Mon Sep 17 00:00:00 2001 From: Arnd Bergmann arnd@arndb.de Date: Tue, 7 Jan 2020 21:15:49 +0100 Subject: [PATCH] scsi: fnic: fix invalid stack access
gcc -O3 warns that some local variables are not properly initialized:
drivers/scsi/fnic/vnic_dev.c: In function 'fnic_dev_hang_notify': drivers/scsi/fnic/vnic_dev.c:511:16: error: 'a0' is used uninitialized in this function [-Werror=uninitialized] vdev->args[0] = *a0;
drivers/scsi/fnic/vnic_dev.c:691:6: note: 'a0' was declared here u64 a0, a1; ^~ drivers/scsi/fnic/vnic_dev.c:512:16: error: 'a1' is used uninitialized in this function [-Werror=uninitialized] vdev->args[1] = *a1; ~~~~~~~~~~~~~~^~~~~ drivers/scsi/fnic/vnic_dev.c:691:10: note: 'a1' was declared here u64 a0, a1; ^~ drivers/scsi/fnic/vnic_dev.c: In function 'fnic_dev_mac_addr': drivers/scsi/fnic/vnic_dev.c:512:16: error: 'a1' is used uninitialized in this function [-Werror=uninitialized] vdev->args[1] = *a1; ~~~~~~~~~~~~~~^~~~~ drivers/scsi/fnic/vnic_dev.c:698:10: note: 'a1' was declared here u64 a0, a1; ^~ Apparently the code relies on the local variables occupying adjacent memory locations in the same order, but this is of course not guaranteed. Use an array of two u64 variables where needed to make it work correctly. I suspect there is also an endianness bug here, but have not digged in deep enough to be sure. Fixes: 5df6d737dd4b ("[SCSI] fnic: Add new Cisco PCI-Express FCoE HBA") Fixes: mmtom ("init/Kconfig: enable -O3 for all arches") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200107201602.4096790-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
I've grabbed 36fe90b0f0bd ("scsi: fnic: use kernel's '%pM' format option to print MAC") to resolve this conflict and queued both for 4.9 and 4.4