# 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-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-5.5.0-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_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- mpc85xx_defconfig # < make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 24 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- In file included from /kisskb/src/include/linux/kernel.h:11:0, 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] #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' # 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' 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 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc94700) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) INFO: Uncompressed kernel (size 0xc83efc) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xd00000) Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169734 Bytes = 6025.13 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169796 Bytes = 6025.19 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6139777 Bytes = 5995.88 KiB = 5.86 MiB Load Address: 00000000 Entry Point: 00000000 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6170005 Bytes = 6025.40 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6170221 Bytes = 6025.61 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6170578 Bytes = 6025.96 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169615 Bytes = 6025.01 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:32 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169796 Bytes = 6025.19 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169644 Bytes = 6025.04 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d00314 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6170023 Bytes = 6025.41 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d00314 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169645 Bytes = 6025.04 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d00314 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169816 Bytes = 6025.21 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d00314 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6169676 Bytes = 6025.07 KiB = 5.88 MiB Load Address: 00d00000 Entry Point: 00d00314 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6171666 Bytes = 6027.02 KiB = 5.89 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6171472 Bytes = 6026.83 KiB = 5.89 MiB Load Address: 00d00000 Entry Point: 00d002a4 Image Name: Linux-5.6.0-rc2-g99793e64b815 Created: Tue Mar 17 02:21:33 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6171005 Bytes = 6026.37 KiB = 5.89 MiB Load Address: 00d00000 Entry Point: 00d002a4 Completed OK # rm -rf /kisskb/build/powerpc-next_mpc85xx_defconfig_powerpc-gcc5 # Build took: 0:02:35.902548