Andrew,
Didn't someone already provide a fix for this one? I thought I saw that hit your tree a while ago. I am looking in ptrace.c and I don't see anything that would have fixed this issue. If there isn't a fix in the queue I will take a stab at it. Thank you Eric syzbot <syzbot+0d602a1b0d8c95bdf...@syzkaller.appspotmail.com> writes: > Hello, > > syzbot found the following crash on: > > HEAD commit: d062d017 usb-fuzzer: main usb gadget fuzzer driver > git tree: kmsan > console output: https://syzkaller.appspot.com/x/log.txt?x=137348b4a00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=67ebf8b3cce62ce7 > dashboard link: https://syzkaller.appspot.com/bug?extid=0d602a1b0d8c95bdf299 > compiler: clang version 9.0.0 (/home/glider/llvm/clang > 06d00afa61eef8f7f501ebdb4e8612ea43ec2d78) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=175d65e0a00000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14ae05c0a00000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+0d602a1b0d8c95bdf...@syzkaller.appspotmail.com > > ptrace attach of "./syz-executor353086472"[10278] was attempted by > "./syz-executor353086472"[10279] > ptrace attach of "./syz-executor353086472"[10280] was attempted by > "./syz-executor353086472"[10281] > ptrace attach of "./syz-executor353086472"[10282] was attempted by > "./syz-executor353086472"[10283] > ================================================================== > BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 > CPU: 1 PID: 10284 Comm: syz-executor353 Not tainted 5.1.0-rc7+ #5 > 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+0x191/0x1f0 lib/dump_stack.c:113 > kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:619 > kmsan_internal_check_memory+0x974/0xa80 mm/kmsan/kmsan.c:713 > kmsan_copy_to_user+0xa9/0xb0 mm/kmsan/kmsan_hooks.c:492 > _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 > copy_to_user include/linux/uaccess.h:174 [inline] > copy_siginfo_to_user+0x80/0x160 kernel/signal.c:3059 > ptrace_peek_siginfo kernel/ptrace.c:742 [inline] > ptrace_request+0x24bd/0x2950 kernel/ptrace.c:913 > arch_ptrace+0x9fa/0x1090 arch/x86/kernel/ptrace.c:868 > __do_sys_ptrace kernel/ptrace.c:1155 [inline] > __se_sys_ptrace+0x2b9/0x7b0 kernel/ptrace.c:1120 > __x64_sys_ptrace+0x56/0x70 kernel/ptrace.c:1120 > do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 > entry_SYSCALL_64_after_hwframe+0x63/0xe7 > RIP: 0033:0x441cc9 > Code: e8 bc e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 1b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00000000007efdd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000065 > RAX: ffffffffffffffda RBX: 0000000000000063 RCX: 0000000000441cc9 > RDX: 00000000200000c0 RSI: 0000000000000007 RDI: 0000000000004209 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000716000 R11: 0000000000000246 R12: 0000000000000002 > R13: 0000000000402a00 R14: 0000000000000000 R15: 0000000000000000 > > Local variable description: ----info.i@ptrace_request > Variable was created at: > ptrace_peek_siginfo kernel/ptrace.c:714 [inline] > ptrace_request+0x2161/0x2950 kernel/ptrace.c:913 > arch_ptrace+0x9fa/0x1090 arch/x86/kernel/ptrace.c:868 > > Bytes 0-47 of 48 are uninitialized > Memory access of size 48 starts at ffff8880a902fd70 > Data copied to user address 0000000000716000 > ================================================================== > > > --- > This bug is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkal...@googlegroups.com. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this bug, for details see: > https://goo.gl/tpsmEJ#testing-patches
