# 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/m68k-linux/bin/m68k-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-ld --version
# < git log --format=%s --max-count=1 2e90ca68b0d2f5548804f22f0dd61145516171e3
# < make -s -j 80 ARCH=m68k O=/kisskb/build/linus_m5272c3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-  m5272c3_defconfig
# < make -s -j 80 ARCH=m68k O=/kisskb/build/linus_m5272c3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-  help
# make -s -j 80 ARCH=m68k O=/kisskb/build/linus_m5272c3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-  olddefconfig
# make -s -j 80 ARCH=m68k O=/kisskb/build/linus_m5272c3_defconfig_m68k CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-  
/kisskb/src/drivers/net/ethernet/freescale/fec_main.c: In function 'fec_restart':
/kisskb/src/drivers/net/ethernet/freescale/fec_main.c:915:6: warning: unused variable 'val' [-Wunused-variable]
  u32 val;
      ^~~
/kisskb/src/drivers/net/ethernet/freescale/fec_main.c: In function 'fec_get_mac':
/kisskb/src/drivers/net/ethernet/freescale/fec_main.c:1643:28: warning: unused variable 'pdata' [-Wunused-variable]
  struct fec_platform_data *pdata = dev_get_platdata(&fep->pdev->dev);
                            ^~~~~
In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7,
                 from /kisskb/src/include/linux/atomic.h:7,
                 from /kisskb/src/include/linux/spinlock.h:445,
                 from /kisskb/src/include/linux/seqlock.h:36,
                 from /kisskb/src/include/linux/time.h:6,
                 from /kisskb/src/include/linux/stat.h:19,
                 from /kisskb/src/include/linux/module.h:13,
                 from /kisskb/src/net/core/filter.c:20:
/kisskb/src/net/core/filter.c: In function 'bpf_clear_redirect_map':
/kisskb/src/arch/m68k/include/asm/cmpxchg.h:137:3: warning: value computed is not used [-Wunused-value]
  ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
  ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    (unsigned long)(n), sizeof(*(ptr))))
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/include/asm-generic/cmpxchg.h:106:28: note: in expansion of macro 'cmpxchg_local'
 #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n))
                            ^~~~~~~~~~~~~
/kisskb/src/net/core/filter.c:3516:4: note: in expansion of macro 'cmpxchg'
    cmpxchg(&ri->map, map, NULL);
    ^~~~~~~
Completed OK
# rm -rf /kisskb/build/linus_m5272c3_defconfig_m68k
# Build took: 0:00:29.480169