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authorAl Viro <viro@zeniv.linux.org.uk>2010-09-18 08:40:07 -0400
committerMatt Turner <mattst88@gmail.com>2010-09-18 23:08:28 -0400
commit392fb6e35400edbee183baba24b34a0fa2053813 (patch)
treee11587c8b7ca75ab41b23f9e09e2c6a9365e2187
parent2deba1bd7126aadb5750beb927c878a6490065e6 (diff)
downloadop-kernel-dev-392fb6e35400edbee183baba24b34a0fa2053813.zip
op-kernel-dev-392fb6e35400edbee183baba24b34a0fa2053813.tar.gz
alpha: unb0rk sigsuspend() and rt_sigsuspend()
Old code used to set regs->r0 and regs->r19 to force the right return value. Leaving that after switch to ERESTARTNOHAND was a Bad Idea(tm), since now that screws the restart - if we hit the case when get_signal_to_deliver() returns 0, we will step back to syscall insn, with v0 set to EINTR and a3 to 1. The latter won't matter, since EINTR is 4, aka __NR_write. Testcase: #include <signal.h> #define _GNU_SOURCE #include <unistd.h> #include <sys/syscall.h> main() { sigset_t mask; sigemptyset(&mask); sigaddset(&mask, SIGCONT); sigprocmask(SIG_SETMASK, &mask, NULL); kill(0, SIGCONT); syscall(__NR_sigsuspend, 1, "b0rken\n", 7); } results on alpha in immediate message to stdout... Fix is obvious; moreover, since we don't need regs anymore, we can switch to normal prototypes for these guys and lose the wrappers. Even better, rt_sigsuspend() is identical to generic version in kernel/signal.c now. Tested-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matt Turner <mattst88@gmail.com>
-rw-r--r--arch/alpha/include/asm/unistd.h1
-rw-r--r--arch/alpha/kernel/entry.S32
-rw-r--r--arch/alpha/kernel/signal.c38
3 files changed, 2 insertions, 69 deletions
diff --git a/arch/alpha/include/asm/unistd.h b/arch/alpha/include/asm/unistd.h
index 9a9672f..058937b 100644
--- a/arch/alpha/include/asm/unistd.h
+++ b/arch/alpha/include/asm/unistd.h
@@ -466,6 +466,7 @@
#define __ARCH_WANT_SYS_OLD_GETRLIMIT
#define __ARCH_WANT_SYS_OLDUMOUNT
#define __ARCH_WANT_SYS_SIGPENDING
+#define __ARCH_WANT_SYS_RT_SIGSUSPEND
/* "Conditional" syscalls. What we want is
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index b45d913..bceb325 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -779,38 +779,6 @@ sys_rt_sigreturn:
.end sys_rt_sigreturn
.align 4
- .globl sys_sigsuspend
- .ent sys_sigsuspend
-sys_sigsuspend:
- .prologue 0
- mov $sp, $17
- br $1, do_switch_stack
- mov $sp, $18
- subq $sp, 16, $sp
- stq $26, 0($sp)
- jsr $26, do_sigsuspend
- ldq $26, 0($sp)
- lda $sp, SWITCH_STACK_SIZE+16($sp)
- ret
-.end sys_sigsuspend
-
- .align 4
- .globl sys_rt_sigsuspend
- .ent sys_rt_sigsuspend
-sys_rt_sigsuspend:
- .prologue 0
- mov $sp, $18
- br $1, do_switch_stack
- mov $sp, $19
- subq $sp, 16, $sp
- stq $26, 0($sp)
- jsr $26, do_rt_sigsuspend
- ldq $26, 0($sp)
- lda $sp, SWITCH_STACK_SIZE+16($sp)
- ret
-.end sys_rt_sigsuspend
-
- .align 4
.globl sys_sethae
.ent sys_sethae
sys_sethae:
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index e5b1b3c..0f6b51a 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -144,8 +144,7 @@ SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
/*
* Atomically swap in the new signal mask, and wait for a signal.
*/
-asmlinkage int
-do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw)
+SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
{
mask &= _BLOCKABLE;
spin_lock_irq(&current->sighand->siglock);
@@ -154,41 +153,6 @@ do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- /* Indicate EINTR on return from any possible signal handler,
- which will not come back through here, but via sigreturn. */
- regs->r0 = EINTR;
- regs->r19 = 1;
-
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- set_thread_flag(TIF_RESTORE_SIGMASK);
- return -ERESTARTNOHAND;
-}
-
-asmlinkage int
-do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize,
- struct pt_regs *regs, struct switch_stack *sw)
-{
- sigset_t set;
-
- /* XXX: Don't preclude handling different sized sigset_t's. */
- if (sigsetsize != sizeof(sigset_t))
- return -EINVAL;
- if (copy_from_user(&set, uset, sizeof(set)))
- return -EFAULT;
-
- sigdelsetmask(&set, ~_BLOCKABLE);
- spin_lock_irq(&current->sighand->siglock);
- current->saved_sigmask = current->blocked;
- current->blocked = set;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
-
- /* Indicate EINTR on return from any possible signal handler,
- which will not come back through here, but via sigreturn. */
- regs->r0 = EINTR;
- regs->r19 = 1;
-
current->state = TASK_INTERRUPTIBLE;
schedule();
set_thread_flag(TIF_RESTORE_SIGMASK);
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