================================================================== BUG: KASAN: wild-memory-access in memcpy include/linux/string.h:339 [inline] BUG: KASAN: wild-memory-access in skb_copy_ubufs+0xc51/0x1940 net/core/skbuff.c:1229 Read of size 4096 at addr 1b91bd495e86926b by task syz-executor1/3889 CPU: 1 PID: 3889 Comm: syz-executor1 Not tainted 4.13.0-rc5-next-20170816+ #4 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 kasan_report_error mm/kasan/report.c:349 [inline] kasan_report+0x12e/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x23/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:339 [inline] skb_copy_ubufs+0xc51/0x1940 net/core/skbuff.c:1229 skb_orphan_frags_rx include/linux/skbuff.h:2548 [inline] __netif_receive_skb_core+0x2084/0x33d0 net/core/dev.c:4415 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4456 netif_receive_skb_internal+0x10b/0x5e0 net/core/dev.c:4527 netif_receive_skb+0xae/0x390 net/core/dev.c:4551 tun_rx_batched.isra.43+0x5e7/0x860 drivers/net/tun.c:1221 tun_get_user+0x11dd/0x2150 drivers/net/tun.c:1542 tun_chr_write_iter+0xd8/0x190 drivers/net/tun.c:1568 call_write_iter include/linux/fs.h:1742 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x40b751 RSP: 002b:00007f46a2d11c10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 000000000040b751 RDX: 0000000000000036 RSI: 0000000020002000 RDI: 0000000000000015 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000f4246 R11: 0000000000000293 R12: 00000000004bab1b R13: 00000000ffffffff R14: 0000000000000055 R15: 0000000020014fab ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3889 Comm: syz-executor1 Tainted: G B 4.13.0-rc5-next-20170816+ #4 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 panic+0x1e4/0x417 kernel/panic.c:180 kasan_end_report+0x50/0x50 mm/kasan/report.c:176 kasan_report_error mm/kasan/report.c:356 [inline] kasan_report+0x137/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x23/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:339 [inline] skb_copy_ubufs+0xc51/0x1940 net/core/skbuff.c:1229 skb_orphan_frags_rx include/linux/skbuff.h:2548 [inline] __netif_receive_skb_core+0x2084/0x33d0 net/core/dev.c:4415 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4456 netif_receive_skb_internal+0x10b/0x5e0 net/core/dev.c:4527 netif_receive_skb+0xae/0x390 net/core/dev.c:4551 tun_rx_batched.isra.43+0x5e7/0x860 drivers/net/tun.c:1221 tun_get_user+0x11dd/0x2150 drivers/net/tun.c:1542 tun_chr_write_iter+0xd8/0x190 drivers/net/tun.c:1568 call_write_iter include/linux/fs.h:1742 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x40b751 RSP: 002b:00007f46a2d11c10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 000000000040b751 RDX: 0000000000000036 RSI: 0000000020002000 RDI: 0000000000000015 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000f4246 R11: 0000000000000293 R12: 00000000004bab1b R13: 00000000ffffffff R14: 0000000000000055 R15: 0000000020014fab Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..