This is a note to let you know that I've just added the patch titled
s390/compat: fix mmap compat system calls
to the 3.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-compat-fix-mmap-compat-system-calls.patch
and it can be found in the queue-3.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From e85871218513c54f7dfdb6009043cb638f2fecbe Mon Sep 17 00:00:00 2001
From: Heiko Carstens <[email protected]>
Date: Wed, 8 Aug 2012 09:32:20 +0200
Subject: s390/compat: fix mmap compat system calls
From: Heiko Carstens <[email protected]>
commit e85871218513c54f7dfdb6009043cb638f2fecbe upstream.
The native 31 bit and the compat behaviour for the mmap system calls differ:
In native 31 bit mode the passed in address for the mmap system call will be
unmodified passed to sys_mmap_pgoff().
In compat mode however the passed in address will be modified with
compat_ptr() which masks out the most significant bit.
The result is that in native 31 bit mode each mmap request (with MAP_FIXED)
will fail where the most significat bit is set, while in compat mode it
may succeed.
This odd behaviour was introduced with d3815898 "[S390] mmap: add missing
compat_ptr conversion to both mmap compat syscalls".
To restore a consistent behaviour accross native and compat mode this
patch functionally reverts the above mentioned commit.
Signed-off-by: Heiko Carstens <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/s390/kernel/compat_linux.c | 2 --
1 file changed, 2 deletions(-)
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -631,7 +631,6 @@ asmlinkage unsigned long old32_mmap(stru
return -EFAULT;
if (a.offset & ~PAGE_MASK)
return -EINVAL;
- a.addr = (unsigned long) compat_ptr(a.addr);
return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
a.offset >> PAGE_SHIFT);
}
@@ -642,7 +641,6 @@ asmlinkage long sys32_mmap2(struct mmap_
if (copy_from_user(&a, arg, sizeof(a)))
return -EFAULT;
- a.addr = (unsigned long) compat_ptr(a.addr);
return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
}
Patches currently in stable-queue which might be from [email protected]
are
queue-3.0/s390-compat-fix-mmap-compat-system-calls.patch
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