aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2006-10-04 20:01:58 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2006-10-04 20:01:58 +0200
commitb05e37035298148b6c311eccf06ac50fd389f0b2 (patch)
tree8ff9dbbc71d7ef9b5ef025d98784bb6b2c1f30c0
parentaa97b102527ff94fe04930a660f897ef2bafb2a8 (diff)
downloadlinux-linaro-b05e37035298148b6c311eccf06ac50fd389f0b2.tar.gz
[S390] user-copy optimization fallout.
Fix new restore_sigregs function. It copies the user space copy of the old psw without correcting the psw.mask and the psw.addr high order bit. While we are at it, simplify save_sigregs a bit. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
-rw-r--r--arch/s390/kernel/signal.c17
1 files changed, 7 insertions, 10 deletions
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 642095ec7c0..4392a77cbae 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -113,17 +113,15 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
/* Returns non-zero on fault. */
static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
{
- unsigned long old_mask = regs->psw.mask;
_sigregs user_sregs;
save_access_regs(current->thread.acrs);
/* Copy a 'clean' PSW mask to the user to avoid leaking
information about whether PER is currently on. */
- regs->psw.mask = PSW_MASK_MERGE(PSW_USER_BITS, regs->psw.mask);
- memcpy(&user_sregs.regs.psw, &regs->psw, sizeof(sregs->regs.psw) +
- sizeof(sregs->regs.gprs));
- regs->psw.mask = old_mask;
+ user_sregs.regs.psw.mask = PSW_MASK_MERGE(PSW_USER_BITS, regs->psw.mask);
+ user_sregs.regs.psw.addr = regs->psw.addr;
+ memcpy(&user_sregs.regs.gprs, &regs->gprs, sizeof(sregs->regs.gprs));
memcpy(&user_sregs.regs.acrs, current->thread.acrs,
sizeof(sregs->regs.acrs));
/*
@@ -139,7 +137,6 @@ static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
/* Returns positive number on error */
static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
{
- unsigned long old_mask = regs->psw.mask;
int err;
_sigregs user_sregs;
@@ -147,12 +144,12 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
current_thread_info()->restart_block.fn = do_no_restart_syscall;
err = __copy_from_user(&user_sregs, sregs, sizeof(_sigregs));
- regs->psw.mask = PSW_MASK_MERGE(old_mask, regs->psw.mask);
- regs->psw.addr |= PSW_ADDR_AMODE;
if (err)
return err;
- memcpy(&regs->psw, &user_sregs.regs.psw, sizeof(sregs->regs.psw) +
- sizeof(sregs->regs.gprs));
+ regs->psw.mask = PSW_MASK_MERGE(regs->psw.mask,
+ user_sregs.regs.psw.mask);
+ regs->psw.addr = PSW_ADDR_AMODE | user_sregs.regs.psw.addr;
+ memcpy(&regs->gprs, &user_sregs.regs.gprs, sizeof(sregs->regs.gprs));
memcpy(&current->thread.acrs, &user_sregs.regs.acrs,
sizeof(sregs->regs.acrs));
restore_access_regs(current->thread.acrs);