mseal sysmap: uprobe mapping

Provide support to mseal the uprobe mapping.

Unlike other system mappings, the uprobe mapping is not established during
program startup.  However, its lifetime is the same as the process's
lifetime.  It could be sealed from creation.

Test was done with perf tool, and observe the uprobe mapping is sealed.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jeff Xu <[email protected]>
Reviewed-by: Oleg Nesterov <[email protected]>
Reviewed-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Liam R. Howlett <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: Adhemerval Zanella <[email protected]>
Cc: Alexander Mikhalitsyn <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Andrei Vagin <[email protected]>
Cc: Anna-Maria Behnsen <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Benjamin Berg <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Elliot Hughes <[email protected]>
Cc: Florian Faineli <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Hyeonggon Yoo <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Jason A. Donenfeld <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: Jorge Lucangeli Obes <[email protected]>
Cc: Linus Waleij <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Matthew Wilcow (Oracle) <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Pedro Falcato <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Stephen Röttger <[email protected]>
Cc: Thomas Weißschuh <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: peaktocreek

kernel/events/uprobes.c

@@ -1703,7 +1703,8 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
 	}
 
 	vma = _install_special_mapping(mm, area->vaddr, PAGE_SIZE,
-				VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO,
+				VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO|
+				VM_SEALED_SYSMAP,
 				&xol_mapping);
 	if (IS_ERR(vma)) {
 		ret = PTR_ERR(vma);