# git rev-parse -q --verify 99793e64b815ec88daa9955c6347bd541e78543b^{commit} 99793e64b815ec88daa9955c6347bd541e78543b already have revision, skipping fetch # git checkout -q -f -B kisskb 99793e64b815ec88daa9955c6347bd541e78543b # git clean -qxdf # < git log -1 # commit 99793e64b815ec88daa9955c6347bd541e78543b # Author: Michael Ellerman # Date: Mon Mar 16 22:32:32 2020 +1100 # # powerpc/64: Prevent stack protection in early boot # # The previous commit reduced the amount of code that is run before we # setup a paca. However there are still a few remaining functions that # run with no paca, or worse, with an arbitrary value in r13 that will # be used as a paca pointer. # # In particular the stack protector canary is stored in the paca, so if # stack protector is activated for any of these functions we will read # the stack canary from wherever r13 points. If r13 happens to point # outside of memory we will get a machine check / checkstop. # # For example if we modify initialise_paca() to trigger stack # protection, and then boot in the mambo simulator with r13 poisoned in # skiboot before calling the kernel: # # DEBUG: 19952232: (19952232): INSTRUCTION: PC=0xC0000000191FC1E8: [0x3C4C006D]: addis r2,r12,0x6D [fetch] # DEBUG: 19952236: (19952236): INSTRUCTION: PC=0xC00000001807EAD8: [0x7D8802A6]: mflr r12 [fetch] # FATAL ERROR: 19952276: (19952276): Check Stop for 0:0: Machine Check with ME bit of MSR off # DEBUG: 19952276: (19952276): INSTRUCTION: PC=0xC0000000191FCA7C: [0xE90D0CF8]: ld r8,0xCF8(r13) [Instruction Failed] # INFO: 19952276: (19952277): ** Execution stopped: Mambo Error, Machine Check Stop, ** # systemsim % bt # pc: 0xC0000000191FCA7C initialise_paca+0x54 # lr: 0xC0000000191FC22C early_setup+0x44 # stack:0x00000000198CBED0 0x0 +0x0 # stack:0x00000000198CBF00 0xC0000000191FC22C early_setup+0x44 # stack:0x00000000198CBF90 0x1801C968 +0x1801C968 # # So annotate the relevant functions to ensure stack protection is never # enabled for them. # # Fixes: 06ec27aea9fc ("powerpc/64: add stack protector support") # Cc: stable@vger.kernel.org # v4.20+ # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 99793e64b815ec88daa9955c6347bd541e78543b # < make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig+KVM_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- mpc85xx_defconfig # Added to kconfig CONFIG_PPC_E500MC=y # Added to kconfig CONFIG_VIRTUALIZATION=y # Added to kconfig CONFIG_KVM_E500MC=y # Added to kconfig # < make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig+KVM_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig+KVM_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig .config:4064:warning: override: reassigning to symbol PPC_E500MC .config:4065:warning: override: reassigning to symbol VIRTUALIZATION # make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig+KVM_powerpc-gcc9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-9.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- In file included from /kisskb/src/include/linux/kernel.h:11, from /kisskb/src/include/linux/list.h:9, from /kisskb/src/include/linux/module.h:12, from /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:15: /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c: In function 'allocate_bd': /kisskb/src/include/linux/err.h:22:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 22 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) | ^ /kisskb/src/include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:139:6: note: in expansion of macro 'IS_ERR_VALUE' 139 | if (IS_ERR_VALUE(fep->ring_mem_addr)) | ^~~~~~~~~~~~ /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8541cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8555cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe629ac) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) INFO: Uncompressed kernel (size 0xe521a8) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:02 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6753715 Bytes = 6595.42 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:02 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6720384 Bytes = 6562.88 KiB = 6.41 MiB Load Address: 00000000 Entry Point: 00000000 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:02 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6751979 Bytes = 6593.73 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f0031c Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:02 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6754227 Bytes = 6595.92 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:03 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755621 Bytes = 6597.29 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:03 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755756 Bytes = 6597.42 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f0031c Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:03 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6753887 Bytes = 6595.59 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:03 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755512 Bytes = 6597.18 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:03 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6752346 Bytes = 6594.09 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755755 Bytes = 6597.42 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f0031c Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6751944 Bytes = 6593.70 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f0031c Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6754099 Bytes = 6595.80 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6751897 Bytes = 6593.65 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755801 Bytes = 6597.46 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f0031c Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6755867 Bytes = 6597.53 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 03:16:04 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6752233 Bytes = 6593.98 KiB = 6.44 MiB Load Address: 00f00000 Entry Point: 00f002cc Completed OK # rm -rf /kisskb/build/powerpc-next_mpc85xx_defconfig+KVM_powerpc-gcc9 # Build took: 0:03:20.827245