frv: fix mmap2 error handling

Fix the error handling in sys_mmap2().  Currently, if the pgoff check
fails, fput() might have to be called (which it isn't), so do the pgoff
check first, before fget() is called.

Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Howells 2008-12-01 13:14:00 -08:00 committed by Linus Torvalds
parent a800599283
commit 4280e3126f

View File

@ -35,6 +35,15 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
int error = -EBADF;
struct file * file = NULL;
/* As with sparc32, make sure the shift for mmap2 is constant
(12), no matter what PAGE_SIZE we have.... */
/* But unlike sparc32, don't just silently break if we're
trying to map something we can't */
if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
return -EINVAL;
pgoff >>= PAGE_SHIFT - 12;
flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
if (!(flags & MAP_ANONYMOUS)) {
file = fget(fd);
@ -42,16 +51,6 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
goto out;
}
/* As with sparc32, make sure the shift for mmap2 is constant
(12), no matter what PAGE_SIZE we have.... */
/* But unlike sparc32, don't just silently break if we're
trying to map something we can't */
if (pgoff & ((1<<(PAGE_SHIFT-12))-1))
return -EINVAL;
pgoff >>= (PAGE_SHIFT - 12);
down_write(&current->mm->mmap_sem);
error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
up_write(&current->mm->mmap_sem);