bisecting fixing commit since cbfa1702aaf69b2311ea1b35e04f113c48368c67 building syzkaller on 5ef9c29141f85f210b326ce68718498ae0c1fd35 testing commit cbfa1702aaf69b2311ea1b35e04f113c48368c67 with gcc (GCC) 8.4.1 20210217 kernel signature: bb5a9cbd511f9fc79fea7da1a95eb8b8a3e9d99677d289a2c0abb24eb4c2b8df all runs: crashed: KASAN: slab-out-of-bounds Read in build_segment_manager testing current HEAD cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217 kernel signature: c99c074f08cb04e0d5e78185522d3a75cf23004d0e99f302e2cfddb435a55356 all runs: crashed: KASAN: slab-out-of-bounds Read in build_segment_manager revisions tested: 2, total time: 21m31.430112073s (build: 14m50.394022404s, test: 6m11.973399949s) the crash still happens on HEAD commit msg: Linux 4.14.231 crash: KASAN: slab-out-of-bounds Read in build_segment_manager F2FS-fs (loop3): Fix alignment : done, start(4096) end(147456) block(12288) IPv6: ADDRCONF(NETDEV_UP): veth1_vlan: link is not ready F2FS-fs (loop3): invalid crc value ================================================================== IPv6: ADDRCONF(NETDEV_UP): macvlan1: link is not ready BUG: KASAN: slab-out-of-bounds in init_min_max_mtime fs/f2fs/segment.c:3497 [inline] BUG: KASAN: slab-out-of-bounds in build_segment_manager+0x806e/0x8690 fs/f2fs/segment.c:3577 Read of size 8 at addr ffff8881d5a0f068 by task syz-executor.3/7200 CPU: 1 PID: 7200 Comm: syz-executor.3 Not tainted 4.14.231-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+0x14b/0x1e7 lib/dump_stack.c:58 print_address_description.cold.6+0x9/0x1ca mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold.7+0x11a/0x2d3 mm/kasan/report.c:393 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 init_min_max_mtime fs/f2fs/segment.c:3497 [inline] build_segment_manager+0x806e/0x8690 fs/f2fs/segment.c:3577 f2fs_fill_super fs/f2fs/super.c:2581 [inline] f2fs_fill_super+0x27ef/0x5d70 fs/f2fs/super.c:2389 mount_bdev+0x26f/0x330 fs/super.c:1134 f2fs_mount+0x10/0x20 fs/f2fs/super.c:2776 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466c8a RSP: 002b:00007f9f3d91efa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000140 RCX: 0000000000466c8a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f9f3d91f000 RBP: 00007f9f3d91f040 R08: 00007f9f3d91f040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f9f3d91f000 R15: 0000000020000200 Allocated by task 7200: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:551 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:536 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node+0x50/0x70 mm/slab.c:3689 kmalloc_node include/linux/slab.h:530 [inline] kvmalloc_node+0x70/0x80 mm/util.c:397 kvmalloc include/linux/mm.h:531 [inline] kvzalloc include/linux/mm.h:539 [inline] build_sit_info fs/f2fs/segment.c:3108 [inline] build_segment_manager+0x9f8/0x8690 fs/f2fs/segment.c:3553 f2fs_fill_super fs/f2fs/super.c:2581 [inline] f2fs_fill_super+0x27ef/0x5d70 fs/f2fs/super.c:2389 mount_bdev+0x26f/0x330 fs/super.c:1134 f2fs_mount+0x10/0x20 fs/f2fs/super.c:2776 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8881d5a0ebc0 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 1192 bytes inside of 2048-byte region [ffff8881d5a0ebc0, ffff8881d5a0f3c0) The buggy address belongs to the page: page:ffffea0007568380 count:1 mapcount:0 mapping:ffff8881d5a0e340 index:0x0 compound_mapcount: 0 flags: 0x17ffe0000008100(slab|head) raw: 017ffe0000008100 ffff8881d5a0e340 0000000000000000 0000000100000003 raw: ffffea0007627e20 ffffea00075756a0 ffff8881f6000c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881d5a0ef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881d5a0ef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881d5a0f000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff8881d5a0f080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881d5a0f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== F2FS-fs (loop3): inconsistent node block, nid:3, node_footer[nid:0,ino:0,ofs:0,cpver:0,blkaddr:0] F2FS-fs (loop3): Failed to read root inode IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready F2FS-fs (loop3): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop3): Can't find valid F2FS filesystem in 1th superblock IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready F2FS-fs (loop3): Small segment_count (31 < 5 * 24) IPv6: ADDRCONF(NETDEV_CHANGE): veth1_vlan: link becomes ready F2FS-fs (loop3): Can't find valid F2FS filesystem in 2th superblock IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready IPv6: ADDRCONF(NETDEV_UP): veth0_macvtap: link is not ready IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 device veth0_vlan entered promiscuous mode wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): veth1_macvtap: link is not ready device veth1_vlan entered promiscuous mode IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready device veth0_macvtap entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): macvtap0: link is not ready IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): veth0_macvtap: link is not ready device veth1_macvtap entered promiscuous mode wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): macsec0: link is not ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): veth1_macvtap: link is not ready wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready IPv6: ADDRCONF(NETDEV_UP): veth0_to_batadv: link is not ready device veth0_macvtap entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): macvtap0: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_0 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready device veth1_macvtap entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): macsec0: link is not ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_1 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): veth0_to_batadv: link is not ready wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_0 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready f2fs_msg: 638 callbacks suppressed F2FS-fs (loop3): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop2): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop3): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop2): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop2): Fix alignment : done, start(4096) end(147456) block(12288) F2FS-fs (loop3): Fix alignment : done, start(4096) end(147456) block(12288) F2FS-fs (loop3): invalid crc value F2FS-fs (loop5): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop4): Magic Mismatch, valid(0xf2f52010) - read(0x0) f2fs_msg: 1015 callbacks suppressed F2FS-fs (loop4): inconsistent node block, nid:3, node_footer[nid:0,ino:0,ofs:0,cpver:0,blkaddr:0] F2FS-fs (loop2): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop4): Failed to read root inode F2FS-fs (loop2): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop2): Small segment_count (31 < 5 * 24) F2FS-fs (loop2): Can't find valid F2FS filesystem in 2th superblock