# git rev-parse -q --verify a68a0262abdaa251e12c53715f48e698a18ef402^{commit}
a68a0262abdaa251e12c53715f48e698a18ef402
already have revision, skipping fetch
# git checkout -q -f -B kisskb a68a0262abdaa251e12c53715f48e698a18ef402
# git clean -qxdf
# < git log -1
# commit a68a0262abdaa251e12c53715f48e698a18ef402
# Author: Minchan Kim <minchan@kernel.org>
# Date:   Tue Dec 8 20:57:18 2020 -0800
# 
#     mm/madvise: remove racy mm ownership check
#     
#     Jann spotted the security hole due to race of mm ownership check.
#     
#     If the task is sharing the mm_struct but goes through execve() before
#     mm_access(), it could skip process_madvise_behavior_valid check.  That
#     makes *any advice hint* to reach into the remote process.
#     
#     This patch removes the mm ownership check.  With it, it will lose the
#     ability that local process could give *any* advice hint with vector
#     interface for some reason (e.g., performance).  Since there is no
#     concrete example in upstream yet, it would be better to remove the
#     abiliity at this moment and need to review when such new advice comes
#     up.
#     
#     Fixes: ecb8ac8b1f14 ("mm/madvise: introduce process_madvise() syscall: an external memory hinting API")
#     Reported-by: Jann Horn <jannh@google.com>
#     Suggested-by: Jann Horn <jannh@google.com>
#     Signed-off-by: Minchan Kim <minchan@kernel.org>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version
# < git log --format=%s --max-count=1 a68a0262abdaa251e12c53715f48e698a18ef402
# < make -s -j 10 ARCH=powerpc O=/kisskb/build/linus_ppc40x_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-  ppc40x_defconfig
# make -s -j 10 ARCH=powerpc O=/kisskb/build/linus_ppc40x_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-  
/kisskb/src/block/genhd.c: In function 'diskstats_show':
/kisskb/src/block/genhd.c:1662:1: warning: the frame size of 1160 bytes is larger than 1024 bytes [-Wframe-larger-than=]
 }
 ^
/kisskb/src/lib/zstd/compress.c: In function 'ZSTD_compressBlock_doubleFast':
/kisskb/src/lib/zstd/compress.c:1393:1: warning: the frame size of 1584 bytes is larger than 1024 bytes [-Wframe-larger-than=]
 }
 ^
INFO: Uncompressed kernel (size 0x5e06f8) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0x600000)
INFO: Uncompressed kernel (size 0x5e06f8) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0x600000)
Image Name:   Linux-5.10.0-rc7-ga68a0262abda
Created:      Wed Dec  9 17:11:02 2020
Image Type:   PowerPC Linux Kernel Image (gzip compressed)
Data Size:    2996582 Bytes = 2926.35 KiB = 2.86 MiB
Load Address: 00600000
Entry Point:  0060198c
Image Name:   Linux-5.10.0-rc7-ga68a0262abda
Created:      Wed Dec  9 17:11:02 2020
Image Type:   PowerPC Linux Kernel Image (gzip compressed)
Data Size:    2995778 Bytes = 2925.56 KiB = 2.86 MiB
Load Address: 00600000
Entry Point:  00601750
Completed OK
# rm -rf /kisskb/build/linus_ppc40x_defconfig_powerpc-gcc4.9
# Build took: 0:01:06.050137