csky: Fix syscall_get_arguments() and syscall_set_arguments()

C-SKY syscall arguments are located in orig_a0,a1,a2,a3,regs[0],regs[1]
fields of struct pt_regs.

Due to an off-by-one bug and a bug in pointer arithmetic
syscall_get_arguments() was reading orig_a0,regs[1..5] fields instead.
Likewise, syscall_set_arguments() was writing orig_a0,regs[1..5] fields
instead.

Link: http://lkml.kernel.org/r/[email protected]

Fixes: 4859bfca11 ("csky: System Call")
Cc: Ingo Molnar <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Will Drewry <[email protected]>
Cc: [email protected] # v4.20+
Tested-by: Guo Ren <[email protected]>
Acked-by: Guo Ren <[email protected]>
Signed-off-by: Dmitry V. Levin <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>
This commit is contained in:
Dmitry V. Levin 2019-03-29 20:12:30 +03:00 • committed by Steven Rostedt (VMware)
commit ed3bb00702

View file

@ -49,10 +49,11 @@ syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
if (i == 0) {
args[0] = regs->orig_a0;
args++;
i++;
n--;
} else {
i--;
}
memcpy(args, &regs->a1 + i * sizeof(regs->a1), n * sizeof(args[0]));
memcpy(args, &regs->a1 + i, n * sizeof(args[0]));
}
static inline void
@ -63,10 +64,11 @@ syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
if (i == 0) {
regs->orig_a0 = args[0];
args++;
i++;
n--;
} else {
i--;
}
memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0));
memcpy(&regs->a1 + i, args, n * sizeof(regs->a1));
}
static inline int