uml: don't allow processes to call into stub

Kill a process that tries to branch into a stub and execute a system
call.  There are no security implications here - a system call in a
stub is treated the same as a system call anywhere else.  But if a
process is trying to branch into a stub, either it is trying something
nasty or it has gone haywire, so it's a good idea to get rid of it in
either case.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jeff Dike 2008-02-04 22:31:12 -08:00 committed by Linus Torvalds
parent a9b71b6c54
commit e06173bde0

View file

@ -146,6 +146,9 @@ static void handle_trap(int pid, struct uml_pt_regs *regs,
{ {
int err, status; int err, status;
if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
fatal_sigsegv();
/* Mark this as a syscall */ /* Mark this as a syscall */
UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp); UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp);