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| author | Cyril Bur <cyrilbur@gmail.com> | 2016-09-23 09:18:12 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-10-04 08:43:07 +0300 |
| commit | d11994314b2bfe028bc39be24b44298787925160 (patch) | |
| tree | 09bf53fd6dfb5958d20f2cc2ab0849a8df17c911 /arch/powerpc/include | |
| parent | e909fb83d39292679118761426d7784715ad79ad (diff) | |
| download | linux-d11994314b2bfe028bc39be24b44298787925160.tar.xz | |
powerpc: signals: Stop using current in signal code
Much of the signal code takes a pt_regs on which it operates. Over
time the signal code has needed to know more about the thread than
what pt_regs can supply, this information is obtained as needed by
using 'current'.
This approach is not strictly incorrect however it does mean that
there is now a hard requirement that the pt_regs being passed around
does belong to current, this is never checked. A safer approach is for
the majority of the signal functions to take a task_struct from which
they can obtain pt_regs and any other information they need. The
caveat that the task_struct they are passed must be current doesn't go
away but can more easily be checked for.
Functions called from outside powerpc signal code are passed a pt_regs
and they can confirm that the pt_regs is that of current and pass
current to other functions, furthurmore, powerpc signal functions can
check that the task_struct they are passed is the same as current
avoiding possible corruption of current (or the task they are passed)
if this assertion ever fails.
CC: paulus@samba.org
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include')
| -rw-r--r-- | arch/powerpc/include/asm/signal.h | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/signal.h b/arch/powerpc/include/asm/signal.h index 9322c28aebd2..5ff77722a52d 100644 --- a/arch/powerpc/include/asm/signal.h +++ b/arch/powerpc/include/asm/signal.h @@ -5,6 +5,4 @@ #include <uapi/asm/signal.h> #include <uapi/asm/ptrace.h> -extern unsigned long get_tm_stackpointer(struct pt_regs *regs); - #endif /* _ASM_POWERPC_SIGNAL_H */ |