# git rev-parse -q --verify fa520c47eaa15b9baa8ad66ac18da4a31679693b^{commit} fa520c47eaa15b9baa8ad66ac18da4a31679693b already have revision, skipping fetch # git checkout -q -f -B kisskb fa520c47eaa15b9baa8ad66ac18da4a31679693b # git clean -qxdf # < git log -1 # commit fa520c47eaa15b9baa8ad66ac18da4a31679693b # Author: Eric Sandeen # Date: Wed Oct 17 15:23:59 2018 +0100 # # fscache: Fix out of bound read in long cookie keys # # fscache_set_key() can incur an out-of-bounds read, reported by KASAN: # # BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x5b3/0x680 [fscache] # Read of size 4 at addr ffff88084ff056d4 by task mount.nfs/32615 # # and also reported by syzbot at https://lkml.org/lkml/2018/7/8/236 # # BUG: KASAN: slab-out-of-bounds in fscache_set_key fs/fscache/cookie.c:120 [inline] # BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171 # Read of size 4 at addr ffff8801d3cc8bb4 by task syz-executor907/4466 # # This happens for any index_key_len which is not divisible by 4 and is # larger than the size of the inline key, because the code allocates exactly # index_key_len for the key buffer, but the hashing loop is stepping through # it 4 bytes (u32) at a time in the buf[] array. # # Fix this by calculating how many u32 buffers we'll need by using # DIV_ROUND_UP, and then using kcalloc() to allocate a precleared allocation # buffer to hold the index_key, then using that same count as the hashing # index limit. # # Fixes: ec0328e46d6e ("fscache: Maintain a catalogue of allocated cookies") # Reported-by: syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com # Signed-off-by: Eric Sandeen # Cc: stable # Signed-off-by: David Howells # Signed-off-by: Greg Kroah-Hartman # < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < git log --format=%s --max-count=1 fa520c47eaa15b9baa8ad66ac18da4a31679693b # < make -s -j 48 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- randconfig KCONFIG_SEED=0x44BB17E3 # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_BUILD_DOCSRC=n # Added to kconfig CONFIG_MODULE_SIG=n # Added to kconfig CONFIG_CPU_BIG_ENDIAN=y # Added to kconfig CONFIG_PPC64=y # Added to kconfig CONFIG_PPC_DISABLE_WERROR=y # Added to kconfig CONFIG_SECTION_MISMATCH_WARN_ONLY=y # Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y # Added to kconfig CONFIG_CC_STACKPROTECTOR_STRONG=n # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig CONFIG_LD_HEAD_STUB_CATCH=y # Added to kconfig # yes \n | make -s -j 48 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- oldconfig yes: standard output: Broken pipe # make -s -j 48 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- /kisskb/src/fs/afs/dir.c: In function 'afs_dir_set_page_dirty': /kisskb/src/fs/afs/dir.c:52:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ /kisskb/src/scripts/unifdef.c: In function 'Mpass': /kisskb/src/scripts/unifdef.c:453:28: warning: 'strncpy' output truncated before terminating nul copying 4 bytes from a string of the same length [-Wstringop-truncation] static void Mpass (void) { strncpy(keyword, "if ", 4); Pelif(); } ^~~~~~~~~~~~~~~~~~~~~~~~~~~ WARNING: 4 bad relocations c00000000001f85e R_PPC64_ADDR16_HIGHEST .head.text+0x000000000001f878 c00000000001f862 R_PPC64_ADDR16_HIGHER .head.text+0x000000000001f878 c00000000001f86a R_PPC64_ADDR16_HIGH .head.text+0x000000000001f878 c00000000001f86e R_PPC64_ADDR16_LO .head.text+0x000000000001f878 Completed OK # rm -rf /kisskb/build/linus-rand_powerpc-randconfig_powerpc-gcc5 # Build took: 0:05:50.969048