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: kernel-infoleak in copy_to_user include/linux/uaccess.h:184 [inline] BUG: KMSAN: kernel-infoleak in copy_from_read_buf+0x311/0x890 drivers/tty/n_tty.c:1955 CPU: 0 PID: 4551 Comm: syz-executor247 Not tainted 4.17.0+ #16 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+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1352 kmsan_internal_check_memory+0x138/0x1f0 mm/kmsan/kmsan.c:1446 kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1488 copy_to_user include/linux/uaccess.h:184 [inline] copy_from_read_buf+0x311/0x890 drivers/tty/n_tty.c:1955 n_tty_read+0x178f/0x2f70 drivers/tty/n_tty.c:2226 tty_read+0x26e/0x6c0 drivers/tty/tty_io.c:865 __vfs_read+0x1b2/0x9d0 fs/read_write.c:416 vfs_read+0x36c/0x6b0 fs/read_write.c:452 ksys_read fs/read_write.c:578 [inline] __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x1bf/0x3e0 fs/read_write.c:586 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x445969 RSP: 002b:00007fcda7f09d18 EFLAGS: 00000297 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00000000006dbc5c RCX: 0000000000445969 RDX: 00000000ffffff5c RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00000000006dbc58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000297 R12: 6d74702f7665642f R13: 00007ffebcfd741f R14: 00007fcda7f0a9c0 R15: 0000000000000001 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:287 [inline] kmsan_alloc_meta_for_pages+0x166/0x3b0 mm/kmsan/kmsan.c:819 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:1061 __alloc_pages_nodemask+0xf7b/0x5cc0 mm/page_alloc.c:4404 alloc_pages_current+0x6b1/0x970 mm/mempolicy.c:2093 alloc_pages include/linux/gfp.h:494 [inline] __vmalloc_area_node mm/vmalloc.c:1702 [inline] __vmalloc_node_range+0x8bf/0x1170 mm/vmalloc.c:1767 __vmalloc_node mm/vmalloc.c:1812 [inline] __vmalloc_node_flags mm/vmalloc.c:1826 [inline] vmalloc+0xd8/0xf0 mm/vmalloc.c:1848 n_tty_open+0x4a/0x490 drivers/tty/n_tty.c:1881 tty_ldisc_open drivers/tty/tty_ldisc.c:466 [inline] tty_ldisc_setup+0x375/0x670 drivers/tty/tty_ldisc.c:776 tty_init_dev+0xb82/0x1020 drivers/tty/tty_io.c:1345 ptmx_open+0x2bb/0x7c0 drivers/tty/pty.c:832 chrdev_open+0xc25/0xd90 fs/char_dev.c:417 do_dentry_open+0xccc/0x1440 fs/open.c:794 vfs_open+0x1b6/0x2f0 fs/open.c:908 do_last fs/namei.c:3365 [inline] path_openat+0x4771/0x6640 fs/namei.c:3506 do_filp_open+0x261/0x640 fs/namei.c:3540 do_sys_open+0x624/0x960 fs/open.c:1101 __do_sys_openat fs/open.c:1128 [inline] __se_sys_openat fs/open.c:1122 [inline] __x64_sys_openat+0x129/0x170 fs/open.c:1122 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Byte 4002 of 4096 is uninitialized Memory access starts at ffffc900018b705e ==================================================================