diff options
| author | H. Peter Anvin <hpa@linux.intel.com> | 2010-09-07 16:16:18 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-09-20 13:17:57 -0700 |
| commit | 337b16213b3810a982e34f4b9497745c700da8a0 (patch) | |
| tree | c411754cab0e44622d6226a9712799029fe9a079 /include | |
| parent | 7764ec137f93bb83dd287d14ad457325072aa00d (diff) | |
compat: Make compat_alloc_user_space() incorporate the access_ok()
commit c41d68a513c71e35a14f66d71782d27a79a81ea6 upstream.
compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area. A missing call could
introduce problems on some architectures.
This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.
This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures. This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.
Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <jejb@parisc-linux.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/compat.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/compat.h b/include/linux/compat.h index af931ee43dd8..cab23f2da4dc 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -309,5 +309,7 @@ asmlinkage long compat_sys_newfstatat(unsigned int dfd, char __user * filename, asmlinkage long compat_sys_openat(unsigned int dfd, const char __user *filename, int flags, int mode); +extern void __user *compat_alloc_user_space(unsigned long len); + #endif /* CONFIG_COMPAT */ #endif /* _LINUX_COMPAT_H */ |