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: 769a8a96229e ("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] Signed-off-by: "Eric W. Biederman" <[email protected]> --- arch/openrisc/kernel/traps.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c index 4085d72fa5ae..9e38dc66c9e4 100644 --- a/arch/openrisc/kernel/traps.c +++ b/arch/openrisc/kernel/traps.c @@ -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); -- 2.14.1
