Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull siginfo updates from Eric Biederman:
 "I have been slowly sorting out siginfo and this is the culmination of
  that work.

  The primary result is in several ways the signal infrastructure has
  been made less error prone. The code has been updated so that manually
  specifying SEND_SIG_FORCED is never necessary. The conversion to the
  new siginfo sending functions is now complete, which makes it
  difficult to send a signal without filling in the proper siginfo
  fields.

  At the tail end of the patchset comes the optimization of decreasing
  the size of struct siginfo in the kernel from 128 bytes to about 48
  bytes on 64bit. The fundamental observation that enables this is by
  definition none of the known ways to use struct siginfo uses the extra
  bytes.

  This comes at the cost of a small user space observable difference.
  For the rare case of siginfo being injected into the kernel only what
  can be copied into kernel_siginfo is delivered to the destination, the
  rest of the bytes are set to 0. For cases where the signal and the
  si_code are known this is safe, because we know those bytes are not
  used. For cases where the signal and si_code combination is unknown
  the bits that won't fit into struct kernel_siginfo are tested to
  verify they are zero, and the send fails if they are not.

  I made an extensive search through userspace code and I could not find
  anything that would break because of the above change. If it turns out
  I did break something it will take just the revert of a single change
  to restore kernel_siginfo to the same size as userspace siginfo.

  Testing did reveal dependencies on preferring the signo passed to
  sigqueueinfo over si->signo, so bit the bullet and added the
  complexity necessary to handle that case.

  Testing also revealed bad things can happen if a negative signal
  number is passed into the system calls. Something no sane application
  will do but something a malicious program or a fuzzer might do. So I
  have fixed the code that performs the bounds checks to ensure negative
  signal numbers are handled"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
  signal: Guard against negative signal numbers in copy_siginfo_from_user32
  signal: Guard against negative signal numbers in copy_siginfo_from_user
  signal: In sigqueueinfo prefer sig not si_signo
  signal: Use a smaller struct siginfo in the kernel
  signal: Distinguish between kernel_siginfo and siginfo
  signal: Introduce copy_siginfo_from_user and use it's return value
  signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
  signal: Fail sigqueueinfo if si_signo != sig
  signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
  signal/unicore32: Use force_sig_fault where appropriate
  signal/unicore32: Generate siginfo in ucs32_notify_die
  signal/unicore32: Use send_sig_fault where appropriate
  signal/arc: Use force_sig_fault where appropriate
  signal/arc: Push siginfo generation into unhandled_exception
  signal/ia64: Use force_sig_fault where appropriate
  signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
  signal/ia64: Use the generic force_sigsegv in setup_frame
  signal/arm/kvm: Use send_sig_mceerr
  signal/arm: Use send_sig_fault where appropriate
  signal/arm: Use force_sig_fault where appropriate
  ...

5 files changed, 9 insertions, 9 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index efae2fb0930a..54207327f98f 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1580,7 +1580,7 @@ static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
 }
 
 static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
-		const siginfo_t *siginfo)
+		const kernel_siginfo_t *siginfo)
 {
 	mm_segment_t old_fs = get_fs();
 	set_fs(KERNEL_DS);
@@ -1782,7 +1782,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
 
 static int fill_note_info(struct elfhdr *elf, int phdrs,
 			  struct elf_note_info *info,
-			  const siginfo_t *siginfo, struct pt_regs *regs)
+			  const kernel_siginfo_t *siginfo, struct pt_regs *regs)
 {
 	struct task_struct *dump_task = current;
 	const struct user_regset_view *view = task_user_regset_view(dump_task);
@@ -2031,7 +2031,7 @@ static int elf_note_info_init(struct elf_note_info *info)
 
 static int fill_note_info(struct elfhdr *elf, int phdrs,
 			  struct elf_note_info *info,
-			  const siginfo_t *siginfo, struct pt_regs *regs)
+			  const kernel_siginfo_t *siginfo, struct pt_regs *regs)
 {
 	struct list_head *t;
 	struct core_thread *ct;
diff --git a/fs/coredump.c b/fs/coredump.c
index 1e2c87acac9b..e42e17e55bfd 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -536,7 +536,7 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
 	return err;
 }
 
-void do_coredump(const siginfo_t *siginfo)
+void do_coredump(const kernel_siginfo_t *siginfo)
 {
 	struct core_state core_state;
 	struct core_name cn;
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 4137d96534a6..083185174c6d 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -735,7 +735,7 @@ static void send_sigio_to_task(struct task_struct *p,
 		return;
 
 	switch (signum) {
-		siginfo_t si;
+		kernel_siginfo_t si;
 		default:
 			/* Queue a rt signal with the appropriate fd as its
 			   value.  We use SI_SIGIO as the source, not 
diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c
index 453a6a1fff34..2b4d5013dc5d 100644
--- a/fs/jffs2/background.c
+++ b/fs/jffs2/background.c
@@ -125,7 +125,7 @@ static int jffs2_garbage_collect_thread(void *_c)
 			if (try_to_freeze())
 				goto again;
 
-			signr = kernel_dequeue_signal(NULL);
+			signr = kernel_dequeue_signal();
 
 			switch(signr) {
 			case SIGSTOP:
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 4fcd1498acf5..757afc7c5895 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -79,7 +79,7 @@ static __poll_t signalfd_poll(struct file *file, poll_table *wait)
  * Copied from copy_siginfo_to_user() in kernel/signal.c
  */
 static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo,
-			     siginfo_t const *kinfo)
+			     kernel_siginfo_t const *kinfo)
 {
 	struct signalfd_siginfo new;
 
@@ -163,7 +163,7 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo,
 	return sizeof(*uinfo);
 }
 
-static ssize_t signalfd_dequeue(struct signalfd_ctx *ctx, siginfo_t *info,
+static ssize_t signalfd_dequeue(struct signalfd_ctx *ctx, kernel_siginfo_t *info,
 				int nonblock)
 {
 	ssize_t ret;
@@ -215,7 +215,7 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count,
 	struct signalfd_siginfo __user *siginfo;
 	int nonblock = file->f_flags & O_NONBLOCK;
 	ssize_t ret, total = 0;
-	siginfo_t info;
+	kernel_siginfo_t info;
 
 	count /= sizeof(struct signalfd_siginfo);
 	if (!count)