# 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/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-gcc --version # < git log --format=%s --max-count=1 fa520c47eaa15b9baa8ad66ac18da4a31679693b # < make -s -j 80 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 allyesconfig # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_KCOV=n # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=n # Added to kconfig CONFIG_GCC_PLUGIN_SANCOV=n # Added to kconfig CONFIG_GCC_PLUGIN_LATENT_ENTROPY=n # Added to kconfig CONFIG_GCC_PLUGIN_STRUCTLEAK=n # Added to kconfig CONFIG_GCC_PLUGIN_RANDSTRUCT=n # Added to kconfig CONFIG_UML_NET=n # Added to kconfig CONFIG_UML_NET_ETHERTAP=n # Added to kconfig CONFIG_UML_NET_TUNTAP=n # Added to kconfig CONFIG_UML_NET_SLIP=n # Added to kconfig CONFIG_UML_NET_DAEMON=n # Added to kconfig CONFIG_UML_NET_VDE=n # Added to kconfig CONFIG_UML_NET_MCAST=n # Added to kconfig CONFIG_UML_NET_PCAP=n # Added to kconfig CONFIG_UML_NET_SLIRP=n # Added to kconfig CONFIG_GCOV_KERNEL=n # yes \n | make -s -j 80 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 oldconfig yes: standard output: Broken pipe # make -s -j 80 ARCH=um O=/kisskb/build/linus_um-allyesconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 /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(); } ^~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/arch/um/os-Linux/skas/process.c: In function 'start_idle_thread': /kisskb/src/arch/um/os-Linux/skas/process.c:613:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ /kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount': /kisskb/src/kernel/cgroup/cgroup-v1.c:1256:3: warning: 'root' may be used uninitialized in this function [-Wmaybe-uninitialized] percpu_ref_reinit(&root->cgrp.self.refcnt); ^ /kisskb/src/security/apparmor/policy_unpack.c: In function 'unpack_trans_table': /kisskb/src/security/apparmor/policy_unpack.c:483:9: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized] str[pos] = ':'; ^ /kisskb/src/lib/lz4/lz4hc_compress.c: In function 'LZ4HC_compress_generic': /kisskb/src/lib/lz4/lz4hc_compress.c:579:1: warning: the frame size of 2144 bytes is larger than 2048 bytes [-Wframe-larger-than=] } ^ /kisskb/src/drivers/i2c/i2c-core-base.c: In function 'i2c_generic_scl_recovery': /kisskb/src/drivers/i2c/i2c-core-base.c:235:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized] if (ret == -EOPNOTSUPP) ^ LINK linux Completed OK # rm -rf /kisskb/build/linus_um-allyesconfig_um-x86_64 # Build took: 0:05:24.658563