# git rev-parse -q --verify 2e90ca68b0d2f5548804f22f0dd61145516171e3^{commit}
2e90ca68b0d2f5548804f22f0dd61145516171e3
already have revision, skipping fetch
# git checkout -q -f -B kisskb 2e90ca68b0d2f5548804f22f0dd61145516171e3
# git clean -qxdf
# < git log -1
# commit 2e90ca68b0d2f5548804f22f0dd61145516171e3
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Fri Feb 21 12:43:35 2020 -0800
# 
#     floppy: check FDC index for errors before assigning it
#     
#     Jordy Zomer reported a KASAN out-of-bounds read in the floppy driver in
#     wait_til_ready().
#     
#     Which on the face of it can't happen, since as Willy Tarreau points out,
#     the function does no particular memory access.  Except through the FDCS
#     macro, which just indexes a static allocation through teh current fdc,
#     which is always checked against N_FDC.
#     
#     Except the checking happens after we've already assigned the value.
#     
#     The floppy driver is a disgrace (a lot of it going back to my original
#     horrd "design"), and has no real maintainer.  Nobody has the hardware,
#     and nobody really cares.  But it still gets used in virtual environment
#     because it's one of those things that everybody supports.
#     
#     The whole thing should be re-written, or at least parts of it should be
#     seriously cleaned up.  The 'current fdc' index, which is used by the
#     FDCS macro, and which is often shadowed by a local 'fdc' variable, is a
#     prime example of how not to write code.
#     
#     But because nobody has the hardware or the motivation, let's just fix up
#     the immediate problem with a nasty band-aid: test the fdc index before
#     actually assigning it to the static 'fdc' variable.
#     
#     Reported-by: Jordy Zomer <jordy@simplyhacker.com>
#     Cc: Willy Tarreau <w@1wt.eu>
#     Cc: Dan Carpenter <dan.carpenter@oracle.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-ld --version
# < git log --format=%s --max-count=1 2e90ca68b0d2f5548804f22f0dd61145516171e3
# < make -s -j 160 ARCH=s390 O=/kisskb/build/linus_s390-allyesconfig_s390x-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-  allyesconfig
# Added to kconfig CONFIG_BUILD_DOCSRC=n
# Added to kconfig CONFIG_MODULE_SIG=n
# < make -s -j 160 ARCH=s390 O=/kisskb/build/linus_s390-allyesconfig_s390x-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-  help
# make -s -j 160 ARCH=s390 O=/kisskb/build/linus_s390-allyesconfig_s390x-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-  olddefconfig
# make -s -j 160 ARCH=s390 O=/kisskb/build/linus_s390-allyesconfig_s390x-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/s390-linux/bin/s390-linux-  
/kisskb/src/lib/test_kasan.c: In function 'kasan_alloca_oob_left':
/kisskb/src/lib/test_kasan.c:529:1: warning: 'kasan_alloca_oob_left' uses dynamic stack allocation
 }
 ^
/kisskb/src/lib/test_kasan.c: In function 'kasan_alloca_oob_right':
/kisskb/src/lib/test_kasan.c:539:1: warning: 'kasan_alloca_oob_right' uses dynamic stack allocation
 }
 ^
/kisskb/src/drivers/input/joystick/analog.c:160:2: warning: #warning Precise timer not defined for this architecture. [-Wcpp]
 #warning Precise timer not defined for this architecture.
  ^~~~~~~
In file included from /kisskb/src/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:40:
/kisskb/src/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c: In function 'mvpp2_setup_bm_pool':
/kisskb/src/drivers/net/ethernet/marvell/mvpp2/mvpp2.h:634:2: warning: overflow in conversion from 'long unsigned int' to 'int' changes value from '18446744073709551584' to '-32' [-Woverflow]
  ((total_size) - NET_SKB_PAD - MVPP2_SKB_SHINFO_SIZE)
  ^
/kisskb/src/drivers/net/ethernet/marvell/mvpp2/mvpp2.h:699:33: note: in expansion of macro 'MVPP2_RX_MAX_PKT_SIZE'
 #define MVPP2_BM_SHORT_PKT_SIZE MVPP2_RX_MAX_PKT_SIZE(MVPP2_BM_SHORT_FRAME_SIZE)
                                 ^~~~~~~~~~~~~~~~~~~~~
/kisskb/src/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:577:41: note: in expansion of macro 'MVPP2_BM_SHORT_PKT_SIZE'
  mvpp2_pools[MVPP2_BM_SHORT].pkt_size = MVPP2_BM_SHORT_PKT_SIZE;
                                         ^~~~~~~~~~~~~~~~~~~~~~~
Completed OK
# rm -rf /kisskb/build/linus_s390-allyesconfig_s390x-gcc8
# Build took: 0:08:30.692882