syzbot
panic: nested locking: kernfs.filesystemRWMutex: (10)
Status:
fixed on 2025/09/19 06:07
Reported-by: syzbot+7b4d0fefa2463e53c401@syzkaller.appspotmail.com
Fix commit:
6448dbe1b799
procfs: release the file system mutex on the error path
First crash: 422d, last: 348d
Sample crash report:
panic: nested locking: kernfs.filesystemRWMutex:
goroutine 606 [running]:
gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*filesystemRWMutex).Lock(0xc0011ee710)
bazel-out/k8-fastbuild/bin/pkg/sentry/fsimpl/kernfs/filesystem_mutex.go:31 +0x4d
gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs.(*Dentry).DecRef(0xc000b8f050, {0x20f3bb0, 0xc001498588})
pkg/sentry/fsimpl/kernfs/kernfs.go:303 +0x116
gvisor.dev/gvisor/pkg/sentry/vfs.(*Dentry).DecRef(0xc000b8f050, {0x20f3bb0, 0xc001498588})
pkg/sentry/vfs/dentry.go:156 +0x68
gvisor.dev/gvisor/pkg/sentry/vfs.VirtualDentry.DecRef({0xc0006251e0?, 0xc000b8f050?}, {0x20f3bb0, 0xc001498588})
pkg/sentry/vfs/vfs.go:1105 +0x5b
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).DecRef.func1()
pkg/sentry/vfs/file_description.go:201 +0x505
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescriptionRefs).DecRef(0xc000934b88, 0xc000e97b80)
bazel-out/k8-fastbuild/bin/pkg/sentry/vfs/file_description_refs.go:133 +0xb4
gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).DecRef(0xc000934b88, {0x20f3bb0, 0xc001498588})
pkg/sentry/vfs/file_description.go:161 +0xa5
gvisor.dev/gvisor/pkg/sentry/kernel.(*FDTable).RemoveIf(0xc00070e440, {0x20f3bb0, 0xc001498588}, 0x1f36640)
pkg/sentry/kernel/fd_table.go:506 +0x1b3
gvisor.dev/gvisor/pkg/sentry/kernel.(*FDTable).DecRef.func1()
pkg/sentry/kernel/fd_table.go:150 +0x65
gvisor.dev/gvisor/pkg/sentry/kernel.(*FDTableRefs).DecRef(0xc00070e440, 0xc000e97d10)
bazel-out/k8-fastbuild/bin/pkg/sentry/kernel/fd_table_refs.go:133 +0xb4
gvisor.dev/gvisor/pkg/sentry/kernel.(*FDTable).DecRef(0xc00070e440, {0x20f3bb0, 0xc001498588})
pkg/sentry/kernel/fd_table.go:149 +0xa5
gvisor.dev/gvisor/pkg/sentry/kernel.(*runExitMain).execute(0xc001498588?, 0xc001498588)
pkg/sentry/kernel/task_exit.go:301 +0x813
gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run(0xc001498588, 0x4f)
pkg/sentry/kernel/task_run.go:97 +0x402
created by gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start in goroutine 638
pkg/sentry/kernel/task_start.go:412 +0x17e
* Struck through repros no longer work on HEAD.