KASAN: null-ptr-deref Write in build_segment

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.14	KASAN: null-ptr-deref Write in build_segment_manager (2)				1	1081d	1081d	0/1	auto-closed as invalid on 2022/04/05 03:48
linux-4.14	KASAN: slab-out-of-bounds Read in build_segment_manager f2fs	C		error	5	651d	1508d	0/1	upstream: reported C repro on 2020/10/05 08:04

================================================================== BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:372 [inline] BUG: KASAN: null-ptr-deref in build_sit_entries fs/f2fs/segment.c:3289 [inline] BUG: KASAN: null-ptr-deref in build_segment_manager+0x4fd2/0x7f40 fs/f2fs/segment.c:3564 Write of size 64 at addr (null) by task syz-executor.0/30539 CPU: 0 PID: 30539 Comm: syz-executor.0 Not tainted 4.14.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 kasan_report_error.cold+0x144/0x194 mm/kasan/report.c:349 kasan_report+0x6f/0x7b mm/kasan/report.c:409 memcpy+0x35/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:372 [inline] build_sit_entries fs/f2fs/segment.c:3289 [inline] build_segment_manager+0x4fd2/0x7f40 fs/f2fs/segment.c:3564 f2fs_fill_super+0x2e21/0x56a0 fs/f2fs/super.c:2581 mount_bdev+0x2b3/0x360 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4608fa RSP: 002b:00007f6cc404fa88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f6cc404fb20 RCX: 00000000004608fa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f6cc404fae0 RBP: 00007f6cc404fae0 R08: 00007f6cc404fb20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020015000 ==================================================================