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36 commits

Author SHA1 Message Date
Jason Baron
909af768e8 coredump: remove VM_ALWAYSDUMP flag
The motivation for this patchset was that I was looking at a way for a
qemu-kvm process, to exclude the guest memory from its core dump, which
can be quite large.  There are already a number of filter flags in
/proc/<pid>/coredump_filter, however, these allow one to specify 'types'
of kernel memory, not specific address ranges (which is needed in this
case).

Since there are no more vma flags available, the first patch eliminates
the need for the 'VM_ALWAYSDUMP' flag.  The flag is used internally by
the kernel to mark vdso and vsyscall pages.  However, it is simple
enough to check if a vma covers a vdso or vsyscall page without the need
for this flag.

The second patch then replaces the 'VM_ALWAYSDUMP' flag with a new
'VM_NODUMP' flag, which can be set by userspace using new madvise flags:
'MADV_DONTDUMP', and unset via 'MADV_DODUMP'.  The core dump filters
continue to work the same as before unless 'MADV_DONTDUMP' is set on the
region.

The qemu code which implements this features is at:

  http://people.redhat.com/~jbaron/qemu-dump/qemu-dump.patch

In my testing the qemu core dump shrunk from 383MB -> 13MB with this
patch.

I also believe that the 'MADV_DONTDUMP' flag might be useful for
security sensitive apps, which might want to select which areas are
dumped.

This patch:

The VM_ALWAYSDUMP flag is currently used by the coredump code to
indicate that a vma is part of a vsyscall or vdso section.  However, we
can determine if a vma is in one these sections by checking it against
the gate_vma and checking for a non-NULL return value from
arch_vma_name().  Thus, freeing a valuable vma bit.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:42 -07:00
Linus Torvalds
90a4c0f51e uml: fix compile for x86-64
Randy Dunlap reports that we get

  arch/x86/um/shared/sysdep/ptrace.h:7:20: error: redefinition of 'regs_return_value'
  arch/x86/um/shared/sysdep/ptrace.h:7:20: note: previous definition of 'regs_return_value' was here

when compiling UML for x86-64.

Stephen Rothwell root-caused it and says:

 "Caused by commit d7e7528bcd ("Audit: push audit success and retcode
  into arch ptrace.h") (another patch that was never in linux-next :-().

  This file now needs protection against double inclusion."

so let's do as the man says.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Analyzed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-18 19:26:11 -08:00
Linus Torvalds
f429ee3b80 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits)
  audit: no leading space in audit_log_d_path prefix
  audit: treat s_id as an untrusted string
  audit: fix signedness bug in audit_log_execve_info()
  audit: comparison on interprocess fields
  audit: implement all object interfield comparisons
  audit: allow interfield comparison between gid and ogid
  audit: complex interfield comparison helper
  audit: allow interfield comparison in audit rules
  Kernel: Audit Support For The ARM Platform
  audit: do not call audit_getname on error
  audit: only allow tasks to set their loginuid if it is -1
  audit: remove task argument to audit_set_loginuid
  audit: allow audit matching on inode gid
  audit: allow matching on obj_uid
  audit: remove audit_finish_fork as it can't be called
  audit: reject entry,always rules
  audit: inline audit_free to simplify the look of generic code
  audit: drop audit_set_macxattr as it doesn't do anything
  audit: inline checks for not needing to collect aux records
  audit: drop some potentially inadvisable likely notations
  ...

Use evil merge to fix up grammar mistakes in Kconfig file.

Bad speling and horrible grammar (and copious swearing) is to be
expected, but let's keep it to commit messages and comments, rather than
expose it to users in config help texts or printouts.
2012-01-17 16:41:31 -08:00
Eric Paris
d7e7528bcd Audit: push audit success and retcode into arch ptrace.h
The audit system previously expected arches calling to audit_syscall_exit to
supply as arguments if the syscall was a success and what the return code was.
Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things
by converting from negative retcodes to an audit internal magic value stating
success or failure.  This helper was wrong and could indicate that a valid
pointer returned to userspace was a failed syscall.  The fix is to fix the
layering foolishness.  We now pass audit_syscall_exit a struct pt_reg and it
in turns calls back into arch code to collect the return value and to
determine if the syscall was a success or failure.  We also define a generic
is_syscall_success() macro which determines success/failure based on if the
value is < -MAX_ERRNO.  This works for arches like x86 which do not use a
separate mechanism to indicate syscall failure.

We make both the is_syscall_success() and regs_return_value() static inlines
instead of macros.  The reason is because the audit function must take a void*
for the regs.  (uml calls theirs struct uml_pt_regs instead of just struct
pt_regs so audit_syscall_exit can't take a struct pt_regs).  Since the audit
function takes a void* we need to use static inlines to cast it back to the
arch correct structure to dereference it.

The other major change is that on some arches, like ia64, MIPS and ppc, we
change regs_return_value() to give us the negative value on syscall failure.
THE only other user of this macro, kretprobe_example.c, won't notice and it
makes the value signed consistently for the audit functions across all archs.

In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old
audit code as the return value.  But the ptrace_64.h code defined the macro
regs_return_value() as regs[3].  I have no idea which one is correct, but this
patch now uses the regs_return_value() function, so it now uses regs[3].

For powerpc we previously used regs->result but now use the
regs_return_value() function which uses regs->gprs[3].  regs->gprs[3] is
always positive so the regs_return_value(), much like ia64 makes it negative
before calling the audit code when appropriate.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion]
Acked-by: Tony Luck <tony.luck@intel.com> [for ia64]
Acked-by: Richard Weinberger <richard@nod.at> [for uml]
Acked-by: David S. Miller <davem@davemloft.net> [for sparc]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
2012-01-17 16:16:56 -05:00
Linus Torvalds
5674124f9f Merge branch 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Move <asm/asm-offsets.h> from trace_syscalls.c to asm/syscall.h
  x86, um: Fix typo in 32-bit system call modifications
  um: Use $(srctree) not $(KBUILD_SRC)
  x86, um: Mark system call tables readonly
  x86, um: Use the same style generated syscall tables as native
  um: Generate headers before generating user-offsets.s
  um: Run host archheaders, allow use of host generated headers
  kbuild, headers.sh: Don't make archheaders explicitly
  x86, syscall: Allow syscall offset to be symbolic
  x86, syscall: Re-fix typo in comment
  x86: Simplify syscallhdr.sh
  x86: Generate system call tables and unistd_*.h from tables
  checksyscalls: Use arch/x86/syscalls/syscall_32.tbl as source
  x86: Machine-readable syscall tables and scripts to process them
  trace: Include <asm/asm-offsets.h> in trace_syscalls.c
  x86-64, ia32: Move compat_ni_syscall into C and its own file
  x86-64, syscall: Adjust comment spacing and remove typo
  kbuild: Add support for an "archheaders" target
  kbuild: Add support for installing generated asm headers
2012-01-16 18:19:19 -08:00
Heiko Carstens
2565409fc0 mm,x86,um: move CMPXCHG_DOUBLE config option
Move CMPXCHG_DOUBLE and rename it to HAVE_CMPXCHG_DOUBLE so architectures
can simply select the option if it is supported.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:03 -08:00
Heiko Carstens
4156153c4d mm,x86,um: move CMPXCHG_LOCAL config option
Move CMPXCHG_LOCAL and rename it to HAVE_CMPXCHG_LOCAL so architectures
can simply select the option if it is supported.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:03 -08:00
H. Peter Anvin
47db9e7c80 x86, um: Fix typo in 32-bit system call modifications
We override sys_iopl(), not stub_iopl(); the latter is a 64-bitism
that doesn't apply to i386 in the first place.

Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-12-09 11:13:59 -08:00
H. Peter Anvin
a074335a37 x86, um: Mark system call tables readonly
Mark the system call tables readonly, as they already are on native,
and the 32-bit UM version was in the previous assembly version.  The
32-bit version lost it due to copy and paste from the 64-bit version,
which was missing the const.

Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/tip-45db1c6176c8171d9ae6fa6d82e07d115a5950ca@git.kernel.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-12-05 22:56:38 -08:00
H. Peter Anvin
45db1c6176 x86, um: Use the same style generated syscall tables as native
Now when the native kernel uses a single style of generated system
call table, follow suite for UML and implement the same style, all in
C.  This requires __NR_syscall_max and NR_syscalls to be generated; on
native this is done in asm-headers.h but that file is common to all
UML architectures; therefore put it in user-headers.h instead which
already have accommodations for architecture-specific values.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-05 16:08:49 -08:00
Al Viro
cc11f9edd9 fix braino in um patchset (mea culpa)
wrong register returned...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-21 12:10:21 -08:00
Linus Torvalds
02ebbbd481 Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  scsi: drop unused Kconfig symbol
  pci: drop unused Kconfig symbol
  stmmac: drop unused Kconfig symbol
  x86: drop unused Kconfig symbol
  powerpc: drop unused Kconfig symbols
  powerpc: 40x: drop unused Kconfig symbol
  mips: drop unused Kconfig symbols
  openrisc: drop unused Kconfig symbols
  arm: at91: drop unused Kconfig symbol
  samples: drop unused Kconfig symbol
  m32r: drop unused Kconfig symbol
  score: drop unused Kconfig symbols
  sh: drop unused Kconfig symbol
  um: drop unused Kconfig symbol
  sparc: drop unused Kconfig symbol
  alpha: drop unused Kconfig symbol

Fix up trivial conflict in drivers/net/ethernet/stmicro/stmmac/Kconfig
as per Michal: the STMMAC_DUAL_MAC config variable is still unused and
should be deleted.
2011-11-06 18:54:53 -08:00
Dave Jones
0d65ede0a6 um: Fix kmalloc argument order in um/vdso/vma.c
kmalloc size is 1st arg, not second.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Cc: <stable@kernel.org> # 3.0.x
[richard@nod.at: on 3.0 the to be patched file is
arch/um/sys-x86_64/vdso/vma.c]
2011-11-02 14:15:42 +01:00
Richard Weinberger
38b64aed78 um: we need sys/user.h only on i386
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:38 +01:00
Richard Weinberger
d0af6cbfa2 um: merge delay_{32,64}.c
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:37 +01:00
Al Viro
a34978cbd9 um: kill system-um.h
most of it belonged in irqflags.h, actually

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:34 +01:00
Al Viro
46ecca8ae1 um: segment.h is x86-only and needed only there
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:33 +01:00
Al Viro
966e803ab1 um: unify ptrace_user.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:27 +01:00
Al Viro
a10c95d84c um: unify KSTK_...
... and switch get_thread_register() to HOST_... for register numbers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:26 +01:00
Al Viro
4d211093e8 um: fix gcov build breakage
a) exports in gmon_syms.c duplicate kernel/gcov/* ones
b) excluding -pg in vdso compile is not enough - -fprofile-arcs
and -ftest-coverage also needs to be excluded

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:26 +01:00
Al Viro
3fb77d7256 um: irq_vectors.h just shadows x86 one
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:24 +01:00
Al Viro
ff9586e98f um: required-features.h is there only to shadow x86 one...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:23 +01:00
Al Viro
8807c1d561 um: asm/apic.h is there only to shadow the x86 one...
... so take it to arch/um/x86/asm.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:22 +01:00
Al Viro
b3ee571e58 um: take ldt.h to arch/x86/um/asm/mm_context.h
it's x86-only and we have no business playing with it in asm/mmu.h; make
the latter have
	struct uml_arch_mm_context arch;
instead of
	struct uml_ldt ldt;
and let arch/<subarch>/um/asm/mm_context.h decide what'll be in there.
While we are at it, kill host_ldt.h - it's not needed in part of places
that include it (we want asm/ldt.h in those) and it can be trivially
expanded into the single remaining one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:21 +01:00
Al Viro
f67aa2ffb7 um: merge signal_{32,64}.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:20 +01:00
Al Viro
fbe9868693 um: no need to play with save_sp in signal frame setup anymore
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:19 +01:00
Al Viro
c7ea591c91 um: increase stack growth cushion in pagefault
analog of [PATCH] i386: let usermode execute the "enter" instruction from
circa 2006.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:19 +01:00
Al Viro
3579a38973 um: merge HOST_... of registers common on i386 and amd64
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:18 +01:00
Al Viro
8edc4147be um: sanitize paths in sys_call_table* includes
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:18 +01:00
Al Viro
1bbd5f21f4 um: merge os-Linux/tls.c into arch/x86/um/os-Linux/tls.c
it's i386-specific; moreover, analogs on other targets have
incompatible interface - PTRACE_GET_THREAD_AREA does exist
elsewhere, but struct user_desc does *not*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:17 +01:00
Al Viro
c5cc32fe14 um: move asm/desc.h into arch/x86/um/asm
its only purpose is to shadow the x86 asm/desc.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:16 +01:00
Al Viro
2014d01878 um: merge host_ldt_{32,64}.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:15 +01:00
Al Viro
09e129a603 um: merge tls_{32,64}.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:15 +01:00
Al Viro
5ade8878e0 um: kill shared/task.h and HOST_TASK_REGS
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:08 +01:00
Al Viro
0acdbbeb6d um: bury unused macros around ptrace.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:05 +01:00
Al Viro
5c48b108ec um: take arch/um/sys-x86 to arch/x86/um
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02 14:15:05 +01:00