signal/openrisc: Fix do_unaligned_access to send the proper signal

While reviewing the signal sending on openrisc the do_unaligned_access
function stood out because it is obviously wrong.  A comment about an
si_code set above when actually si_code is never set.  Leading to a
random si_code being sent to userspace in the event of an unaligned
access.

Looking further SIGBUS BUS_ADRALN is the proper pair of signal and
si_code to send for an unaligned access. That is what other
architectures do and what is required by posix.

Given that do_unaligned_access is broken in a way that no one can be
relying on it on openrisc fix the code to just do the right thing.

Cc: [email protected]
Fixes: 769a8a9622 ("OpenRISC: Traps")
Cc: Jonas Bonn <[email protected]>
Cc: Stefan Kristiansson <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: [email protected]
Acked-by: Stafford Horne <[email protected]>
Signed-off-by: "Eric W. Biederman" <[email protected]>
This commit is contained in:
Eric W. Biederman 2017-08-01 04:16:47 -05:00
commit 500d583005

View file

@ -266,12 +266,12 @@ asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
siginfo_t info;
if (user_mode(regs)) {
/* Send a SIGSEGV */
info.si_signo = SIGSEGV;
/* Send a SIGBUS */
info.si_signo = SIGBUS;
info.si_errno = 0;
/* info.si_code has been set above */
info.si_addr = (void *)address;
force_sig_info(SIGSEGV, &info, current);
info.si_code = BUS_ADRALN;
info.si_addr = (void __user *)address;
force_sig_info(SIGBUS, &info, current);
} else {
printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
show_registers(regs);