On Tue, Jul 18, 2017 at 4:55 PM, Alexander Potapenko <glider@xxxxxxxxxx> wrote: > KMSAN reported use of uninitialized sctp_addr->v4.sin_addr.s_addr and > sctp_addr->v6.sin6_scope_id in sctp_v6_cmp_addr() (see below). > Make sure all fields of an IPv6 address are initialized, which > guarantees that the IPv4 fields are also initialized. I'm assuming here that the IPv4 address is known to overlap with the IPv6 one and doesn't need separate initialization. > ================================================================== > BUG: KMSAN: use of uninitialized memory in sctp_v6_cmp_addr+0x8d4/0x9f0 > net/sctp/ipv6.c:517 > CPU: 2 PID: 31056 Comm: syz-executor1 Not tainted 4.11.0-rc5+ #2944 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs > 01/01/2011 > Call Trace: > dump_stack+0x172/0x1c0 lib/dump_stack.c:42 > is_logbuf_locked mm/kmsan/kmsan.c:59 [inline] > kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:938 > native_save_fl arch/x86/include/asm/irqflags.h:18 [inline] > arch_local_save_flags arch/x86/include/asm/irqflags.h:72 [inline] > arch_local_irq_save arch/x86/include/asm/irqflags.h:113 [inline] > __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:467 > sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 > sctp_v6_get_dst+0x8c7/0x1630 net/sctp/ipv6.c:290 > sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 > sctp_assoc_add_peer+0x66d/0x16f0 net/sctp/associola.c:651 > sctp_sendmsg+0x35a5/0x4f90 net/sctp/socket.c:1871 > inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 > sock_sendmsg_nosec net/socket.c:633 [inline] > sock_sendmsg net/socket.c:643 [inline] > SYSC_sendto+0x608/0x710 net/socket.c:1696 > SyS_sendto+0x8a/0xb0 net/socket.c:1664 > entry_SYSCALL_64_fastpath+0x13/0x94 > RIP: 0033:0x44b479 > RSP: 002b:00007f6213f21c08 EFLAGS: 00000286 ORIG_RAX: 000000000000002c > RAX: ffffffffffffffda RBX: 0000000020000000 RCX: 000000000044b479 > RDX: 0000000000000041 RSI: 0000000020edd000 RDI: 0000000000000006 > RBP: 00000000007080a8 R08: 0000000020b85fe4 R09: 000000000000001c > R10: 0000000000040005 R11: 0000000000000286 R12: 00000000ffffffff > R13: 0000000000003760 R14: 00000000006e5820 R15: 0000000000ff8000 > origin description: ----dst_saddr@sctp_v6_get_dst > local variable created at: > sk_fullsock include/net/sock.h:2321 [inline] > inet6_sk include/linux/ipv6.h:309 [inline] > sctp_v6_get_dst+0x91/0x1630 net/sctp/ipv6.c:241 > sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 > ================================================================== > BUG: KMSAN: use of uninitialized memory in sctp_v6_cmp_addr+0x8d4/0x9f0 > net/sctp/ipv6.c:517 > CPU: 2 PID: 31056 Comm: syz-executor1 Not tainted 4.11.0-rc5+ #2944 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs > 01/01/2011 > Call Trace: > dump_stack+0x172/0x1c0 lib/dump_stack.c:42 > is_logbuf_locked mm/kmsan/kmsan.c:59 [inline] > kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:938 > native_save_fl arch/x86/include/asm/irqflags.h:18 [inline] > arch_local_save_flags arch/x86/include/asm/irqflags.h:72 [inline] > arch_local_irq_save arch/x86/include/asm/irqflags.h:113 [inline] > __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:467 > sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 > sctp_v6_get_dst+0x8c7/0x1630 net/sctp/ipv6.c:290 > sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 > sctp_assoc_add_peer+0x66d/0x16f0 net/sctp/associola.c:651 > sctp_sendmsg+0x35a5/0x4f90 net/sctp/socket.c:1871 > inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 > sock_sendmsg_nosec net/socket.c:633 [inline] > sock_sendmsg net/socket.c:643 [inline] > SYSC_sendto+0x608/0x710 net/socket.c:1696 > SyS_sendto+0x8a/0xb0 net/socket.c:1664 > entry_SYSCALL_64_fastpath+0x13/0x94 > RIP: 0033:0x44b479 > RSP: 002b:00007f6213f21c08 EFLAGS: 00000286 ORIG_RAX: 000000000000002c > RAX: ffffffffffffffda RBX: 0000000020000000 RCX: 000000000044b479 > RDX: 0000000000000041 RSI: 0000000020edd000 RDI: 0000000000000006 > RBP: 00000000007080a8 R08: 0000000020b85fe4 R09: 000000000000001c > R10: 0000000000040005 R11: 0000000000000286 R12: 00000000ffffffff > R13: 0000000000003760 R14: 00000000006e5820 R15: 0000000000ff8000 > origin description: ----dst_saddr@sctp_v6_get_dst > local variable created at: > sk_fullsock include/net/sock.h:2321 [inline] > inet6_sk include/linux/ipv6.h:309 [inline] > sctp_v6_get_dst+0x91/0x1630 net/sctp/ipv6.c:241 > sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 > ================================================================== > > Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> > --- > net/sctp/ipv6.c | 2 ++ I've also checked the that the corresponding IPv4 code doesn't need to be fixed (nor does KMSAN report errors in it) > 1 file changed, 2 insertions(+) > > diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c > index 2a186b201ad2..a15d691829c6 100644 > --- a/net/sctp/ipv6.c > +++ b/net/sctp/ipv6.c > @@ -513,6 +513,8 @@ static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, > addr->sa.sa_family = AF_INET6; > addr->v6.sin6_port = port; > addr->v6.sin6_addr = *saddr; > + addr->v6.sin6_flowinfo = 0; > + addr->v6.sin6_scope_id = 0; > } > > /* Compare addresses exactly. > -- > 2.13.2.932.g7449e964c-goog > -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
