bisecting cause commit starting from 57fbdb15ec427ca3a6f35d4b71fc90ca9af301ea building syzkaller on 6a81331a1d4c744da9204d02ec88d558f7eea9c9 testing commit 57fbdb15ec427ca3a6f35d4b71fc90ca9af301ea with gcc (GCC) 10.2.1 20210217 kernel signature: b762d878149aa0ba1e044cae3536f4a04ef82bd1ca4f837081824ea37779437f all runs: crashed: WARNING in inc_nlink testing release v5.11 testing commit f40ddce88593482919761f74910f42f4b84c004b with gcc (GCC) 10.2.1 20210217 kernel signature: 44f58b074a2b4030a1bedf2f1cdddcbbe15c92ffea3b784ca4f9f31b88987f51 all runs: crashed: WARNING in inc_nlink testing release v5.10 testing commit 2c85ebc57b3e1817b6ce1a6b703928e113a90442 with gcc (GCC) 10.2.1 20210217 kernel signature: 4742733baa9bf82e241d783d026dc2511126290e27e7df12714b205c43255576 all runs: crashed: WARNING in inc_nlink testing release v5.9 testing commit bbf5c979011a099af5dc76498918ed7df445635b with gcc (GCC) 10.2.1 20210217 kernel signature: c5db40808f8354789d304b4248372764a0a9e3bd6067aa6a6a0663ace87ac3ea all runs: crashed: WARNING in inc_nlink testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c with gcc (GCC) 8.4.1 20210217 kernel signature: 5d5db905a29e886d4efedddc7c045cb6d7fa040cd3d9de48e0aa78c1d3357e75 all runs: crashed: WARNING in inc_nlink testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 with gcc (GCC) 8.4.1 20210217 kernel signature: 694927f270c924473baa1645cf3e46211382cdeb91db268c2363cc6797b41fe8 all runs: crashed: WARNING in inc_nlink testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.4.1 20210217 kernel signature: 465f1dc5ded474a9ba5e43cca9cc1f09bb05d55f63916e1ebe569728cad5a636 all runs: crashed: WARNING in inc_nlink testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.4.1 20210217 kernel signature: f1d2a0134f8956f9ec716cd240a833897b5a62b5431e35e60d334d883749072c all runs: crashed: WARNING in inc_nlink testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.4.1 20210217 kernel signature: 3f14fbf3ee94b7ec709f4176de692fad28379a6cfdd4afa08aa82c70055fb1ab all runs: crashed: WARNING in inc_nlink testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.4.1 20210217 kernel signature: 457310f91ce51f11704650ffedc537752ec21d945a9ab917b17d3db488e81e9f all runs: crashed: WARNING in inc_nlink testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.4.1 20210217 kernel signature: d72b319b5c0a1755226290b310bc5da8fa78ef184a54efbf54bf35811920753a all runs: crashed: WARNING in inc_nlink testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.4.1 20210217 kernel signature: e18d60d4abca9aa170fd650ee96b5d20dd778a0c0c8601a1bf629f9523bff87b all runs: crashed: WARNING in inc_nlink testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.4.1 20210217 kernel signature: f4ab1fd68d4038dbaccea33c38e3381f646886b0064dd3932478472b03b29136 run #0: crashed: WARNING in inc_nlink run #1: crashed: WARNING in inc_nlink run #2: crashed: WARNING in corrupted run #3: crashed: WARNING in inc_nlink run #4: crashed: WARNING in inc_nlink run #5: crashed: WARNING in corrupted run #6: crashed: WARNING in corrupted run #7: crashed: WARNING in inc_nlink run #8: crashed: WARNING in inc_nlink run #9: crashed: WARNING in inc_nlink testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.4.1 20210217 kernel signature: 88c5e47e4b3cd497241abd09e8fe179190c67d684958add7d5a78524a399e856 run #0: crashed: WARNING in inc_nlink run #1: crashed: WARNING in inc_nlink run #2: crashed: WARNING in inc_nlink run #3: crashed: WARNING in corrupted run #4: crashed: WARNING in inc_nlink run #5: crashed: WARNING in inc_nlink run #6: crashed: WARNING in inc_nlink run #7: crashed: WARNING in inc_nlink run #8: crashed: WARNING in inc_nlink run #9: crashed: WARNING in inc_nlink testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.4.1 20210217 kernel signature: 4e25510d19dfce4b85c28ce369a2e1b8f2e629c81dc24ba5d2d7002300875397 run #0: crashed: WARNING in inc_nlink run #1: crashed: WARNING in inc_nlink run #2: crashed: WARNING in inc_nlink run #3: crashed: WARNING in inc_nlink run #4: crashed: WARNING in inc_nlink run #5: crashed: WARNING in corrupted run #6: crashed: WARNING in inc_nlink run #7: crashed: WARNING in inc_nlink run #8: crashed: WARNING in inc_nlink run #9: crashed: WARNING in inc_nlink testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.4.1 20210217 kernel signature: d47d9eb6239b21f8383982983343067a49e20432531ff4da0d95d2c91bba0d93 all runs: crashed: WARNING in inc_nlink testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.4.1 20210217 failed to run ["make" "-j" "64" "ARCH=x86_64" "CC=/syzkaller/shared/bisect_bin/gcc-8.1.0/bin/gcc" "bzImage"]: exit status 2 testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.4.1 20210217 orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.4.1 20210217 orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.4.1 20210217 orc_dump.c:105:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:110:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:139:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:144:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:149:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 with gcc (GCC) 7.5.0 elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:122:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:127:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] revisions tested: 16, total time: 2h35m22.947577222s (build: 1h41m47.219465199s, test: 48m35.174056624s) the crash already happened on the oldest tested release commit msg: Linux 4.18 crash: WARNING in inc_nlink IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready VFS: Found a V7 FS (block size = 512) on device loop0 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_UP): wlan1: link is not ready WARNING: CPU: 1 PID: 9961 at fs/inode.c:342 inc_nlink+0x125/0x140 fs/inode.c:341 Kernel panic - not syncing: panic_on_warn set ... IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready CPU: 1 PID: 9961 Comm: syz-executor.0 Not tainted 4.18.0-syzkaller #0 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 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+0x15a/0x20d lib/dump_stack.c:113 panic+0x1c6/0x36b kernel/panic.c:184 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 __warn.cold.7+0x120/0x168 kernel/panic.c:536 report_bug+0x1a1/0x200 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] fixup_bug arch/x86/kernel/traps.c:173 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ieee80211 phy8: Selected rate control algorithm 'minstrel_ht' do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992 RIP: 0010:inc_nlink+0x125/0x140 fs/inode.c:342 Code: 4c 89 e7 89 45 e4 e8 8a 30 f1 ff 8b 45 ieee80211 phy9: Selected rate control algorithm 'minstrel_ht' e4 e9 53 ff ff ff 4c 89 e7 e8 da 2f f1 ff e9 1a ff ff ff 4c 89 e7 e8 IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready cd wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 2f f1 ff eb ce <0f> 0b e9 72 ff ff ff e8 df 2f f1 ff e9 5b VFS: Found a V7 FS (block size = 512) on device loop5 ff ff ff e8 d5 2f f1 ff RSP: 0018:ffff88008a17fda0 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88008ae1c038 RCX: ffff88008ae1c058 RDX: 1ffff100115c3822 RSI: ffff8800985dadc0 RDI: ffff88008ae1c110 RBP: ffff88008a17fdc0 R08: ffff88008a17fcd8 R09: ffff88008a17fd00 R10: 0000000000000000 R11: ffff88008a17fd1f R12: ffff88008ae1c080 R13: ffff8800985dadc0 R14: 0000000000000021 R15: ffff8800985dae18 inode_inc_link_count include/linux/fs.h:2061 [inline] sysv_mkdir+0x18/0x100 fs/sysv/namei.c:131 WARNING: CPU: 0 PID: 10001 at fs/inode.c:342 inc_nlink+0x125/0x140 fs/inode.c:341 vfs_mkdir+0x37f/0x620 fs/namei.c:3827 Modules linked in: do_mkdirat+0x1c2/0x220 fs/namei.c:3850 CPU: 0 PID: 10001 Comm: syz-executor.5 Not tainted 4.18.0-syzkaller #0 __do_sys_mkdir fs/namei.c:3866 [inline] __se_sys_mkdir fs/namei.c:3864 [inline] __x64_sys_mkdir+0x57/0x80 fs/namei.c:3864 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:inc_nlink+0x125/0x140 fs/inode.c:342 do_syscall_64+0xda/0x540 arch/x86/entry/common.c:290 Code: entry_SYSCALL_64_after_hwframe+0x49/0xbe 4c RIP: 0033:0x466459 89 Code: e7 ff 89 ff 45 c3 e4 66 e8 2e 8a 30 0f f1 1f 84 ff 00 8b 45 00 00 e4 00 00 e9 0f 53 1f ff 40 00 ff 48 ff 89 4c f8 48 89 e7 89 e8 da f7 48 2f 89 f1 d6 ff 48 e9 89 ca 1a 4d 89 ff ff c2 4d ff 89 4c c8 89 4c e7 8b 4c e8 24 cd 2f 08 0f f1 ff 05 eb ce <48> <0f> 0b 3d e9 01 72 ff f0 ff ff ff ff e8 73 df 01 2f c3 f1 ff 48 e9 5b c7 ff c1 ff bc ff ff e8 d5 ff 2f ff f1 ff f7 d8 RSP: 0018:ffff8800a228fda0 EFLAGS: 00010246 64 89 01 48 RAX: dffffc0000000000 RBX: ffff88008ae6c038 RCX: ffff88008ae6c058 RSP: 002b:00007f9226a6d188 EFLAGS: 00000246 RDX: 1ffff100115cd822 RSI: ffff8800964162c0 RDI: ffff88008ae6c110 ORIG_RAX: 0000000000000053 RBP: ffff8800a228fdc0 R08: ffff8800a228fcd8 R09: ffff8800a228fd00 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 R10: 0000000000000000 R11: ffff8800a228fd1f R12: ffff88008ae6c080 RDX: 0000000000000000 RSI: 0000000000000023 RDI: 0000000020000080 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R13: ffff8800964162c0 R14: 0000000000000021 R15: ffff880096416318 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc3908587f R14: 00007f9226a6d300 R15: 0000000000022000 FS: 00007fa8097c5700(0000) GS:ffff8800ba600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000520cd0 CR3: 00000000a15c6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: inode_inc_link_count include/linux/fs.h:2061 [inline] sysv_mkdir+0x18/0x100 fs/sysv/namei.c:131 vfs_mkdir+0x37f/0x620 fs/namei.c:3827 do_mkdirat+0x1c2/0x220 fs/namei.c:3850 __do_sys_mkdir fs/namei.c:3866 [inline] __se_sys_mkdir fs/namei.c:3864 [inline] __x64_sys_mkdir+0x57/0x80 fs/namei.c:3864 do_syscall_64+0xda/0x540 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466459 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa8097c5188 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000000 RSI: 0000000000000023 RDI: 0000000020000080 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff7bc2e84f R14: 00007fa8097c5300 R15: 0000000000022000 irq event stamp: 638 hardirqs last enabled at (637): [] quarantine_put+0xff/0x1c0 mm/kasan/quarantine.c:209 hardirqs last disabled at (638): [] error_entry+0x80/0xd0 arch/x86/entry/entry_64.S:1261 softirqs last enabled at (158): [] spin_unlock_bh include/linux/spinlock.h:355 [inline] softirqs last enabled at (158): [] peernet2id+0x8b/0xc0 net/core/net_namespace.c:265 softirqs last disabled at (156): [] spin_lock_bh include/linux/spinlock.h:315 [inline] softirqs last disabled at (156): [] peernet2id+0x6d/0xc0 net/core/net_namespace.c:263 ---[ end trace af80bcecefcb36d8 ]--- Kernel Offset: disabled Rebooting in 86400 seconds..