linux/include
Oleg Nesterov 485d527686 sys_personality: change sys_personality() to accept "unsigned int" instead of u_long
task_struct->pesonality is "unsigned int", but sys_personality() paths use
"unsigned long pesonality".  This means that every assignment or
comparison is not right.  In particular, if this argument does not fit
into "unsigned int" __set_personality() changes the caller's personality
and then sys_personality() returns -EINVAL.

Turn this argument into "unsigned int" and avoid overflows.  Obviously,
this is the user-visible change, we just ignore the upper bits.  But this
can't break the sane application.

There is another thing which can confuse the poorly written applications.
User-space thinks that this syscall returns int, not long.  This means
that the returned value can be negative and look like the error code.  But
note that libc won't be confused and thus errno won't be set, and with
this patch the user-space can never get -1 unless sys_personality() really
fails.  And, most importantly, the negative RET != -1 is only possible if
that app previously called personality(RET).

Pointed-out-by: Wenming Zhang <wezhang@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
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>
2010-06-04 15:21:45 -07:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-05-28 14:42:18 -07:00
asm-generic Merge branch 'for-35' of git://repo.or.cz/linux-kbuild 2010-06-01 08:55:52 -07:00
crypto crypto: skcipher - Add ablkcipher_walk interfaces 2010-05-19 14:13:07 +10:00
drm Merge branch 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-06-03 07:19:45 -07:00
keys
linux sys_personality: change sys_personality() to accept "unsigned int" instead of u_long 2010-06-04 15:21:45 -07:00
math-emu
media V4L/DVB: v4l2-subdev.h: Add support for enum_dv_preset 2010-05-19 12:59:01 -03:00
mtd
net net: sock_queue_err_skb() dont mess with sk_forward_alloc 2010-05-31 23:44:05 -07:00
pcmcia pcmcia: remove unused mem_op.h 2010-05-10 10:23:20 +02:00
rdma IB/core: Allow device-specific per-port sysfs files 2010-05-21 10:34:44 -07:00
rxrpc
scsi SCSI: implement sd_unlock_native_capacity() 2010-06-02 13:50:04 -04:00
sound Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 2010-05-20 09:41:44 -07:00
trace Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-06-03 15:47:51 -07:00
video fbdev: move FBIO_WAITFORVSYNC to linux/fb.h 2010-05-25 08:07:09 -07:00
xen include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
Kbuild