Revision a622b40035d16196bf19b2b33b854862595245fc authored by Eric Dumazet on 30 April 2019, 13:27:58 UTC, committed by David S. Miller on 30 April 2019, 15:35:48 UTC
Before taking a refcount on a rcu protected structure, we need to make sure the refcount is not zero. syzbot reported : refcount_t: increment on 0; use-after-free. WARNING: CPU: 1 PID: 23533 at lib/refcount.c:156 refcount_inc_checked lib/refcount.c:156 [inline] WARNING: CPU: 1 PID: 23533 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 23533 Comm: syz-executor.2 Not tainted 5.1.0-rc7+ #93 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x2cb/0x65c kernel/panic.c:214 __warn.cold+0x20/0x45 kernel/panic.c:571 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 RIP: 0010:refcount_inc_checked lib/refcount.c:156 [inline] RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Code: 1d 98 2b 2a 06 31 ff 89 de e8 db 2c 40 fe 84 db 75 dd e8 92 2b 40 fe 48 c7 c7 20 7a a1 87 c6 05 78 2b 2a 06 01 e8 7d d9 12 fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 RSP: 0018:ffff888069f0fba8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000000000f353 RSI: ffffffff815afcb6 RDI: ffffed100d3e1f67 RBP: ffff888069f0fbb8 R08: ffff88809b1845c0 R09: ffffed1015d23ef1 R10: ffffed1015d23ef0 R11: ffff8880ae91f787 R12: ffff8880a8f26968 R13: 0000000000000004 R14: dffffc0000000000 R15: ffff8880a49a6440 l2tp_tunnel_inc_refcount net/l2tp/l2tp_core.h:240 [inline] l2tp_tunnel_get+0x250/0x580 net/l2tp/l2tp_core.c:173 pppol2tp_connect+0xc00/0x1c70 net/l2tp/l2tp_ppp.c:702 __sys_connect+0x266/0x330 net/socket.c:1808 __do_sys_connect net/socket.c:1819 [inline] __se_sys_connect net/socket.c:1816 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1816 Fixes: 54652eb12c1b ("l2tp: hold tunnel while looking up sessions in l2tp_netlink") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
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atomic | ||
basic | ||
coccinelle | ||
dtc | ||
gcc-plugins | ||
gdb | ||
genksyms | ||
kconfig | ||
ksymoops | ||
mod | ||
package | ||
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tracing | ||
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Kbuild.include | -rw-r--r-- | 13.0 KB |
Kconfig.include | -rw-r--r-- | 852 bytes |
Lindent | -rwxr-xr-x | 502 bytes |
Makefile | -rw-r--r-- | 1.6 KB |
Makefile.asm-generic | -rw-r--r-- | 1.8 KB |
Makefile.build | -rw-r--r-- | 17.0 KB |
Makefile.clean | -rw-r--r-- | 2.8 KB |
Makefile.dtbinst | -rw-r--r-- | 1.1 KB |
Makefile.extrawarn | -rw-r--r-- | 2.7 KB |
Makefile.gcc-plugins | -rw-r--r-- | 2.4 KB |
Makefile.headersinst | -rw-r--r-- | 3.8 KB |
Makefile.host | -rw-r--r-- | 6.3 KB |
Makefile.kasan | -rw-r--r-- | 1.4 KB |
Makefile.kcov | -rw-r--r-- | 319 bytes |
Makefile.lib | -rw-r--r-- | 15.0 KB |
Makefile.modbuiltin | -rw-r--r-- | 1.7 KB |
Makefile.modinst | -rw-r--r-- | 1.1 KB |
Makefile.modpost | -rw-r--r-- | 5.3 KB |
Makefile.modsign | -rw-r--r-- | 897 bytes |
Makefile.ubsan | -rw-r--r-- | 926 bytes |
adjust_autoksyms.sh | -rwxr-xr-x | 2.8 KB |
asn1_compiler.c | -rw-r--r-- | 35.5 KB |
bin2c.c | -rw-r--r-- | 743 bytes |
bloat-o-meter | -rwxr-xr-x | 3.3 KB |
bootgraph.pl | -rwxr-xr-x | 6.3 KB |
bpf_helpers_doc.py | -rwxr-xr-x | 15.5 KB |
cc-can-link.sh | -rwxr-xr-x | 166 bytes |
check_extable.sh | -rwxr-xr-x | 4.9 KB |
checkincludes.pl | -rwxr-xr-x | 1.9 KB |
checkkconfigsymbols.py | -rwxr-xr-x | 15.5 KB |
checkpatch.pl | -rwxr-xr-x | 196.9 KB |
checkstack.pl | -rwxr-xr-x | 5.3 KB |
checksyscalls.sh | -rwxr-xr-x | 7.3 KB |
checkversion.pl | -rwxr-xr-x | 1.9 KB |
clang-version.sh | -rwxr-xr-x | 527 bytes |
cleanfile | -rwxr-xr-x | 3.5 KB |
cleanpatch | -rwxr-xr-x | 5.1 KB |
coccicheck | -rwxr-xr-x | 7.2 KB |
config | -rwxr-xr-x | 4.5 KB |
conmakehash.c | -rw-r--r-- | 6.0 KB |
const_structs.checkpatch | -rw-r--r-- | 964 bytes |
decode_stacktrace.sh | -rwxr-xr-x | 3.9 KB |
decodecode | -rwxr-xr-x | 2.6 KB |
depmod.sh | -rwxr-xr-x | 1.3 KB |
diffconfig | -rwxr-xr-x | 3.7 KB |
documentation-file-ref-check | -rwxr-xr-x | 3.7 KB |
export_report.pl | -rwxr-xr-x | 4.5 KB |
extract-cert.c | -rw-r--r-- | 3.5 KB |
extract-ikconfig | -rwxr-xr-x | 1.7 KB |
extract-module-sig.pl | -rwxr-xr-x | 3.7 KB |
extract-sys-certs.pl | -rwxr-xr-x | 3.7 KB |
extract-vmlinux | -rwxr-xr-x | 1.7 KB |
extract_xc3028.pl | -rwxr-xr-x | 44.6 KB |
faddr2line | -rwxr-xr-x | 6.2 KB |
file-size.sh | -rwxr-xr-x | 86 bytes |
find-unused-docs.sh | -rwxr-xr-x | 1.3 KB |
gcc-goto.sh | -rwxr-xr-x | 511 bytes |
gcc-ld | -rwxr-xr-x | 711 bytes |
gcc-plugin.sh | -rwxr-xr-x | 1.1 KB |
gcc-version.sh | -rwxr-xr-x | 588 bytes |
gcc-x86_32-has-stack-protector.sh | -rwxr-xr-x | 173 bytes |
gcc-x86_64-has-stack-protector.sh | -rwxr-xr-x | 198 bytes |
gen_compile_commands.py | -rwxr-xr-x | 5.6 KB |
gen_ksymdeps.sh | -rwxr-xr-x | 399 bytes |
get_dvb_firmware | -rwxr-xr-x | 25.2 KB |
get_maintainer.pl | -rwxr-xr-x | 65.8 KB |
gfp-translate | -rwxr-xr-x | 1.7 KB |
headerdep.pl | -rwxr-xr-x | 3.5 KB |
headers.sh | -rwxr-xr-x | 512 bytes |
headers_check.pl | -rwxr-xr-x | 3.7 KB |
headers_install.sh | -rwxr-xr-x | 1.4 KB |
insert-sys-cert.c | -rw-r--r-- | 8.9 KB |
kallsyms.c | -rw-r--r-- | 17.9 KB |
kernel-doc | -rwxr-xr-x | 60.7 KB |
ld-version.sh | -rwxr-xr-x | 269 bytes |
leaking_addresses.pl | -rwxr-xr-x | 12.8 KB |
link-vmlinux.sh | -rwxr-xr-x | 6.1 KB |
makelst | -rwxr-xr-x | 808 bytes |
markup_oops.pl | -rwxr-xr-x | 8.1 KB |
mkcompile_h | -rwxr-xr-x | 2.5 KB |
mkmakefile | -rwxr-xr-x | 866 bytes |
mksysmap | -rwxr-xr-x | 1.3 KB |
mkuboot.sh | -rwxr-xr-x | 414 bytes |
module-common.lds | -rw-r--r-- | 901 bytes |
namespace.pl | -rwxr-xr-x | 13.0 KB |
objdiff | -rwxr-xr-x | 2.8 KB |
parse-maintainers.pl | -rw-r--r-- | 3.7 KB |
patch-kernel | -rwxr-xr-x | 9.9 KB |
pnmtologo.c | -rw-r--r-- | 11.9 KB |
profile2linkerlist.pl | -rwxr-xr-x | 414 bytes |
prune-kernel | -rwxr-xr-x | 708 bytes |
recordmcount.c | -rw-r--r-- | 16.7 KB |
recordmcount.h | -rw-r--r-- | 16.4 KB |
recordmcount.pl | -rwxr-xr-x | 18.7 KB |
setlocalversion | -rwxr-xr-x | 4.3 KB |
show_delta | -rwxr-xr-x | 3.0 KB |
sign-file.c | -rw-r--r-- | 9.8 KB |
sortextable.c | -rw-r--r-- | 8.4 KB |
sortextable.h | -rw-r--r-- | 5.5 KB |
spdxcheck-test.sh | -rw-r--r-- | 323 bytes |
spdxcheck.py | -rwxr-xr-x | 9.8 KB |
spelling.txt | -rw-r--r-- | 28.1 KB |
sphinx-pre-install | -rwxr-xr-x | 14.0 KB |
split-man.pl | -rwxr-xr-x | 600 bytes |
stackdelta | -rwxr-xr-x | 1.8 KB |
stackusage | -rwxr-xr-x | 794 bytes |
subarch.include | -rw-r--r-- | 641 bytes |
tags.sh | -rwxr-xr-x | 10.0 KB |
unifdef.c | -rw-r--r-- | 34.8 KB |
ver_linux | -rwxr-xr-x | 2.7 KB |
xen-hypercalls.sh | -rw-r--r-- | 386 bytes |
xz_wrap.sh | -rwxr-xr-x | 562 bytes |
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