Commit Graph

9 Commits

Author SHA1 Message Date
Paul Moore
8b4b9f27e5 x86: remove the x32 syscall bitmask from syscall_get_nr()
Commit fca460f95e simplified the x32
implementation by creating a syscall bitmask, equal to 0x40000000, that
could be applied to x32 syscalls such that the masked syscall number
would be the same as a x86_64 syscall.  While that patch was a nice
way to simplify the code, it went a bit too far by adding the mask to
syscall_get_nr(); returning the masked syscall numbers can cause
confusion with callers that expect syscall numbers matching the x32
ABI, e.g. unmasked syscall numbers.

This patch fixes this by simply removing the mask from syscall_get_nr()
while preserving the other changes from the original commit.  While
there are several syscall_get_nr() callers in the kernel, most simply
check that the syscall number is greater than zero, in this case this
patch will have no effect.  Of those remaining callers, they appear
to be few, seccomp and ftrace, and from my testing of seccomp without
this patch the original commit definitely breaks things; the seccomp
filter does not correctly filter the syscalls due to the difference in
syscall numbers in the BPF filter and the value from syscall_get_nr().
Applying this patch restores the seccomp BPF filter functionality on
x32.

I've tested this patch with the seccomp BPF filters as well as ftrace
and everything looks reasonable to me; needless to say general usage
seemed fine as well.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Link: http://lkml.kernel.org/r/20130215172143.12549.10292.stgit@localhost
Cc: <stable@vger.kernel.org>
Cc: Will Drewry <wad@chromium.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-02 14:38:09 -07:00
Will Drewry
b7456536cf arch/x86: add syscall_get_arch to syscall.h
Add syscall_get_arch() to export the current AUDIT_ARCH_* based on system call
entry path.

Signed-off-by: Will Drewry <wad@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>

v18: - update comment about x32 tasks
     - rebase to v3.4-rc2
v17: rebase and reviewed-by
v14: rebase/nochanges
v13: rebase on to 88ebdda615
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-14 11:13:20 +10:00
H. Peter Anvin
fca460f95e x32: Handle the x32 system call flag
x32 shares most system calls with x86-64, but unfortunately some
subsystem (the input subsystem is the chief offender) which require
is_compat() when operating with a 32-bit userspace.  The input system
actually has text files in sysfs whose meaning is dependent on
sizeof(long) in userspace!

We could solve this by having two completely disjoint system call
tables; requiring that each system call be duplicated.  This patch
takes a different approach: we add a flag to the system call number;
this flag doesn't affect the system call dispatch but requests compat
treatment from affected subsystems for the duration of the system call.

The change of cmpq to cmpl is safe since it immediately follows the
and.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 12:52:05 -08:00
H. Peter Anvin
72142fd410 x86: Move <asm/asm-offsets.h> from trace_syscalls.c to asm/syscall.h
This reverts commit d5e553d6e0, which
caused large numbers of build warnings on PowerPC.

This moves the #include <asm/asm-offsets.h> to <asm/syscall.h>, which
makes some kind of sense since NR_syscalls is syscalls related.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20111214181545.6e13bc954cb7ddce9086e861@canb.auug.org.au
2012-01-07 14:10:18 -08:00
Mike Frysinger
e7b8e675d9 tracing: Unify arch_syscall_addr() implementations
Most implementations of arch_syscall_addr() are the same, so create a
default version in common code and move the one piece that differs (the
syscall table) to asm/syscall.h.  New arch ports don't have to waste
time copying & pasting this simple function.

The s390/sparc versions need to be different, so document why.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1264498803-17278-1-git-send-email-vapier@gentoo.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-02-17 13:07:21 +01:00
Roland McGrath
18c1e2c80d x86: syscall_get_nr returns int
Make syscall_get_nr() return int, so we always sign-extend
the low 32 bits of orig_ax in checks.

Signed-off-by: Roland McGrath <roland@redhat.com>
2009-09-22 19:57:51 -07:00
Linus Torvalds
c3c9897c63 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: fix section mismatch warning - apic_x2apic_phys
  x86: fix section mismatch warning - apic_x2apic_cluster
  x86: fix section mismatch warning - apic_x2apic_uv_x
  x86: fix section mismatch warning - apic_physflat
  x86: fix section mismatch warning - apic_flat
  x86: memtest fix use of reserve_early()
  x86 syscall.h: fix argument order
  x86/tlb_uv: remove strange mc146818rtc include
  x86: remove redundant KERN_DEBUG on pr_debug
  x86: do_boot_cpu - check if we have ESR register
  x86: MAINTAINERS change for AMD microcode patch loader
  x86/proc: fix /proc/cpuinfo cpu offline bug
  x86: call dmi-quirks for HP Laptops after early-quirks are executed
  x86, kexec: fix hang on i386 when panic occurs while console_sem is held
  MCE: Don't run 32bit machine checks with interrupts on
  x86: SB600: skip IRQ0 override if it is not routed to INT2 of IOAPIC
  x86: make variables static
2008-10-23 12:38:39 -07:00
H. Peter Anvin
5e1b00758b x86: canonicalize remaining header guards
Canonicalize a few remaining header guards, with the exception for
those which are still in subarchitecture directories.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-23 00:20:33 -07:00
Al Viro
bb8985586b x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:20 -07:00