panic: runtime error: invalid memory address or nil pointer dereference (20)

Status: fixed on 2023/11/02 02:06
Fix commit: 429f7c439616 Move rootfs check to inside mountMu.
First crash: 1038d, last: 1031d
▶ ▼ Similar bugs (30)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
gvisor panic: runtime error: invalid memory address or nil pointer dereference (18) 2 4 1084d 1085d 26/26 fixed on 2023/09/13 00:17
gvisor panic: runtime error: invalid memory address or nil pointer dereference (29) 2 syz, C 7 358d 362d 26/26 fixed on 2025/09/19 06:07
gvisor panic: runtime error: invalid memory address or nil pointer dereference (9) 2 syz, C 262 1665d 1662d 14/26 fixed on 2022/02/10 01:56
gvisor panic: runtime error: invalid memory address or nil pointer dereference (7) 2 syz, C 45305 1767d 1796d 14/26 fixed on 2021/10/27 00:49
gvisor panic: runtime error: invalid memory address or nil pointer dereference (3) 2 syz, C 20051 2188d 2723d 0/26 fixed on 2020/09/09 05:34
gvisor panic: runtime error: invalid memory address or nil pointer dereference (23) 2 syz, C 4239 893d 898d 26/26 fixed on 2024/03/19 11:42
gvisor panic: runtime error: invalid memory address or nil pointer dereference (31) 2 syz, C 169 119d 120d 26/26 fixed on 2026/05/01 11:36
gvisor panic: runtime error: invalid memory address or nil pointer dereference (22) 2 1 1003d 1003d 26/26 fixed on 2023/12/01 06:13
gvisor panic: runtime error: invalid memory address or nil pointer dereference (10) 2 syz, C 11 1618d 1624d 14/26 fixed on 2022/03/25 11:21
gvisor panic: runtime error: invalid memory address or nil pointer dereference (12) 2 syz, C 31 1317d 1378d 18/26 fixed on 2023/01/23 05:20
gvisor panic: runtime error: invalid memory address or nil pointer dereference (28) 2 syz, C 21 563d 564d 26/26 fixed on 2025/02/13 10:39
gvisor panic: runtime error: invalid memory address or nil pointer dereference (26) 2 syz, C 7905 645d 653d 26/26 fixed on 2024/11/22 02:29
gvisor panic: runtime error: invalid memory address or nil pointer dereference (21) 2 1 1017d 1017d 26/26 fixed on 2023/11/17 08:30
gvisor panic: runtime error: invalid memory address or nil pointer dereference (14) 2 syz, C 753 1277d 1278d 18/26 fixed on 2023/02/28 09:05
gvisor panic: runtime error: invalid memory address or nil pointer dereference 2 syz, C 20682 2936d 2989d 0/26 fixed on 2018/08/19 04:32
gvisor panic: runtime error: invalid memory address or nil pointer dereference (25) 2 1 755d 755d 26/26 fixed on 2024/08/06 09:03
gvisor panic: runtime error: invalid memory address or nil pointer dereference (27) 2 syz, C 1117 643d 645d 26/26 fixed on 2024/11/23 14:37
gvisor panic: runtime error: invalid memory address or nil pointer dereference (24) 2 92 886d 886d 0/26 closed as invalid on 2024/03/26 13:32
gvisor panic: runtime error: invalid memory address or nil pointer dereference (13) 2 syz, C 2752 1278d 1282d 18/26 fixed on 2023/02/27 08:23
gvisor panic: runtime error: invalid memory address or nil pointer dereference (8) 2 syz, C 214 1669d 1694d 14/26 fixed on 2022/02/01 22:27
gvisor panic: runtime error: invalid memory address or nil pointer dereference (2) 2 syz, C 4493 2911d 2932d 0/26 fixed on 2018/10/15 18:31
gvisor panic: runtime error: invalid memory address or nil pointer dereference (17) 2 2 1121d 1121d 26/26 fixed on 2023/08/04 01:52
gvisor panic: runtime error: invalid memory address or nil pointer dereference (5) 2 syz 62 2062d 2106d 14/26 fixed on 2021/01/06 10:11
gvisor panic: runtime error: invalid memory address or nil pointer dereference (32) 2 syz 6 61d 54d 26/26 fixed on 2026/07/07 11:38
gvisor panic: runtime error: invalid memory address or nil pointer dereference (11) 2 syz, C 2733 1387d 1481d 14/26 fixed on 2022/11/11 17:56
gvisor panic: runtime error: invalid memory address or nil pointer dereference (19) 2 syz, C 79 1059d 1073d 26/26 fixed on 2023/10/05 23:05
gvisor panic: runtime error: invalid memory address or nil pointer dereference (16) 2 syz, C 48 1123d 1130d 26/26 fixed on 2023/08/02 12:57
gvisor panic: runtime error: invalid memory address or nil pointer dereference (30) 2 syz, C 16194 337d 337d 26/26 fixed on 2025/09/26 06:32
gvisor panic: runtime error: invalid memory address or nil pointer dereference (15) 2 1 1170d 1170d 26/26 fixed on 2023/07/12 19:22
gvisor panic: runtime error: invalid memory address or nil pointer dereference (4) 2 syz, C 4 2122d 2140d 0/26 fixed on 2020/11/13 09:22

Sample crash report:
panic: runtime error: invalid memory address or nil pointer dereference
	panic: nested locking: vfs.virtualFilesystemMutex:
goroutine 407 [running]:
gvisor.dev/gvisor/pkg/sentry/vfs.(*virtualFilesystemMutex).Lock(0xc0001de1d8)
	bazel-out/k8-fastbuild-ST-3dcbe13c9b87/bin/pkg/sentry/vfs/virtual_filesystem_mutex.go:33 +0x3c
gvisor.dev/gvisor/pkg/sentry/vfs.(*VirtualFilesystem).lockMounts(...)
	pkg/sentry/vfs/vfs.go:1013
gvisor.dev/gvisor/pkg/sentry/vfs.(*Mount).destroy(0xc0004a64d0, {0x7eb838, 0xc0004d6000})
	pkg/sentry/vfs/mount.go:820 +0x66
gvisor.dev/gvisor/pkg/sentry/vfs.(*Mount).DecRef(0xc0004a64d0, {0x7eb838, 0xc0004d6000})
	pkg/sentry/vfs/mount.go:815 +0x79
gvisor.dev/gvisor/pkg/sentry/vfs.VirtualDentry.DecRef({0xc0004a64d0?, 0xc000b1a800?}, {0x7eb838, 0xc0004d6000})
	pkg/sentry/vfs/vfs.go:1086 +0x85
panic({0x30b000?, 0x260b600?})
	GOROOT/src/runtime/panic.go:920 +0x270
gvisor.dev/gvisor/pkg/sentry/vfs.(*VirtualFilesystem).PivotRoot(0xc0001de1d8, {0x7eb838?, 0xc0004d6000}, 0xc0007d7000?, 0xc00019f100?, 0x7?)
	pkg/sentry/vfs/mount.go:1058 +0x86f
gvisor.dev/gvisor/pkg/sentry/syscalls/linux.PivotRoot(0xc0004d6000, 0xc00067f598?, {{0x20000280}, {0x200002c0}, {0x55db45fc80c6}, {0x0}, {0x7f0e10830a87}, {0x0}})
	pkg/sentry/syscalls/linux/sys_file.go:425 +0x365
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc0004d6000, 0x9b, {{0x20000280}, {0x200002c0}, {0x55db45fc80c6}, {0x0}, {0x7f0e10830a87}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:142 +0x8b5
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc0004d6000, 0x2525b60?, {{0x20000280}, {0x200002c0}, {0x55db45fc80c6}, {0x0}, {0x7f0e10830a87}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:322 +0x6c
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc00067fb58?, 0x208a459?, {{0x20000280}, {0x200002c0}, {0x55db45fc80c6}, {0x0}, {0x7f0e10830a87}, {0x0}})
	pkg/sentry/kernel/task_syscall.go:282 +0x87
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc0004d6000)
	pkg/sentry/kernel/task_syscall.go:257 +0x4f0
gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute(0xc0004d6000?, 0xc0004d6000)
	pkg/sentry/kernel/task_run.go:269 +0x1e08
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc0004d6000, 0x22)
	pkg/sentry/kernel/task_run.go:98 +0x43b
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 378
	pkg/sentry/kernel/task_start.go:391 +0x1ae

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/01 18:12 gvisor 4a8f42267b66 69904c9f .config console log report syz C ci-gvisor-ptrace-1-race panic: runtime error: invalid memory address or nil pointer dereference
2023/11/01 18:09 gvisor 4a8f42267b66 69904c9f .config console log report syz C ci-gvisor-systrap-1-race panic: runtime error: invalid memory address or nil pointer dereference
2023/11/02 00:37 gvisor 4a8f42267b66 69904c9f .config console log report syz ci-gvisor-ptrace-1-race-cover panic: runtime error: invalid memory address or nil pointer dereference
2023/11/01 18:44 gvisor 4a8f42267b66 69904c9f .config console log report syz ci-gvisor-ptrace-2-race panic: runtime error: invalid memory address or nil pointer dereference
2023/11/01 15:39 gvisor 4a8f42267b66 69904c9f .config console log report syz ci-gvisor-ptrace-2-race-cover panic: runtime error: invalid memory address or nil pointer dereference
2023/11/01 14:41 gvisor 4a8f42267b66 69904c9f .config console log report syz ci-gvisor-systrap-1-race-cover panic: runtime error: invalid memory address or nil pointer dereference
2023/11/01 13:50 gvisor 4a8f42267b66 69904c9f .config console log report info ci-gvisor-systrap-1-race-cover panic: runtime error: invalid memory address or nil pointer dereference
2023/10/25 21:42 gvisor d4973670c3c9 72e794c4 console log report info ci-gvisor-kvm panic: runtime error: invalid memory address or nil pointer dereference
* Struck through repros no longer work on HEAD.