syzbot has found a reproducer for the following crash on:
HEAD commit: 25114c64b719 kmsan: unpoison pages moved from iov_iter to ..
git tree: https://github.com/google/kmsan.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=14465da6400000
kernel config: https://syzkaller.appspot.com/x/.config?x=3431f03869413153
dashboard link: https://syzkaller.appspot.com/bug?extid=0049bebbf3042dbd2e8f
compiler: clang version 8.0.0 (trunk 339414)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13b8513e400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10d64e96400000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+0049bebbf3042dbd2e8f@xxxxxxxxxxxxxxxxxxxxxxxxx
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KMSAN: uninit-value in rds_connect+0x213/0x950 net/rds/af_rds.c:511
CPU: 0 PID: 4780 Comm: syz-executor239 Not tainted 4.19.0-rc1+ #38
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+0x14b/0x190 lib/dump_stack.c:113
kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
__msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
rds_connect+0x213/0x950 net/rds/af_rds.c:511
__sys_connect+0x64e/0x750 net/socket.c:1662
__do_sys_connect net/socket.c:1673 [inline]
__se_sys_connect net/socket.c:1670 [inline]
__x64_sys_connect+0xd8/0x120 net/socket.c:1670
do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440199
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff5f41c118 EFLAGS: 00000213 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440199
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a20
R13: 0000000000401ab0 R14: 0000000000000000 R15: 0000000000000000
Local variable description: ----address@__sys_connect
Variable was created at:
__sys_connect+0x6a/0x750 net/socket.c:1645
__do_sys_connect net/socket.c:1673 [inline]
__se_sys_connect net/socket.c:1670 [inline]
__x64_sys_connect+0xd8/0x120 net/socket.c:1670
==================================================================