Commit 11089f08 authored by Laurent MEYER's avatar Laurent MEYER Committed by Paul Mackerras

[PATCH] powerpc: fix incorrect SA_ONSTACK behaviour for 64-bit processes

*) When setting a sighandler using sigaction() call, if the flag
SA_ONSTACK is set and no alternate stack is provided via sigaltstack(),
the kernel still try to install the alternate stack. This behavior is
the opposite of the one which is documented in Single Unix
Specifications V3.

*) Also when setting an alternate stack using sigaltstack() with the
flag SS_DISABLE, the kernel try to install the alternate stack on
signal delivery.

These two use cases makes the process crash at signal delivery.

This fixes it.
Signed-off-by: default avatarLaurent Meyer <meyerlau@fr.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 5149fa47
......@@ -212,7 +212,7 @@ static inline void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs
/* Default to using normal stack */
newsp = regs->gpr[1];
if (ka->sa.sa_flags & SA_ONSTACK) {
if ((ka->sa.sa_flags & SA_ONSTACK) && current->sas_ss_size) {
if (! on_sig_stack(regs->gpr[1]))
newsp = (current->sas_ss_sp + current->sas_ss_size);
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment