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| author | David Gibson <david@gibson.dropbear.id.au> | 2007-08-30 23:56:40 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-08-31 01:42:23 -0700 |
| commit | dec4ad86c2fbea062e9ef9caa6d6e79f7c5e0b12 (patch) | |
| tree | 9882d3b1f59fb293cf0f70afc80bdc7bb1e0021e /fs/hugetlbfs | |
| parent | 4a58448b0a375f7198de34dd0d3e2881afeaf025 (diff) | |
| download | kernel_samsung_crespo-dec4ad86c2fbea062e9ef9caa6d6e79f7c5e0b12.zip kernel_samsung_crespo-dec4ad86c2fbea062e9ef9caa6d6e79f7c5e0b12.tar.gz kernel_samsung_crespo-dec4ad86c2fbea062e9ef9caa6d6e79f7c5e0b12.tar.bz2 | |
hugepage: fix broken check for offset alignment in hugepage mappings
For hugepage mappings, the file offset, like the address and size, needs to
be aligned to the size of a hugepage.
In commit 68589bc353037f233fe510ad9ff432338c95db66, the check for this was
moved into prepare_hugepage_range() along with the address and size checks.
But since BenH's rework of the get_unmapped_area() paths leading up to
commit 4b1d89290b62bb2db476c94c82cf7442aab440c8, prepare_hugepage_range()
is only called for MAP_FIXED mappings, not for other mappings. This means
we're no longer ever checking for an aligned offset - I've confirmed that
mmap() will (apparently) succeed with a misaligned offset on both powerpc
and i386 at least.
This patch restores the check, removing it from prepare_hugepage_range()
and putting it back into hugetlbfs_file_mmap(). I'm putting it there,
rather than in the get_unmapped_area() path so it only needs to go in one
place, than separately in the half-dozen or so arch-specific
implementations of hugetlb_get_unmapped_area().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/hugetlbfs')
| -rw-r--r-- | fs/hugetlbfs/inode.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index c848a19..950c2fb 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -82,14 +82,19 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) int ret; /* - * vma alignment has already been checked by prepare_hugepage_range. - * If you add any error returns here, do so after setting VM_HUGETLB, - * so is_vm_hugetlb_page tests below unmap_region go the right way - * when do_mmap_pgoff unwinds (may be important on powerpc and ia64). + * vma address alignment (but not the pgoff alignment) has + * already been checked by prepare_hugepage_range. If you add + * any error returns here, do so after setting VM_HUGETLB, so + * is_vm_hugetlb_page tests below unmap_region go the right + * way when do_mmap_pgoff unwinds (may be important on powerpc + * and ia64). */ vma->vm_flags |= VM_HUGETLB | VM_RESERVED; vma->vm_ops = &hugetlb_vm_ops; + if (vma->vm_pgoff & ~(HPAGE_MASK >> PAGE_SHIFT)) + return -EINVAL; + vma_len = (loff_t)(vma->vm_end - vma->vm_start); mutex_lock(&inode->i_mutex); @@ -132,7 +137,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, return -ENOMEM; if (flags & MAP_FIXED) { - if (prepare_hugepage_range(addr, len, pgoff)) + if (prepare_hugepage_range(addr, len)) return -EINVAL; return addr; } |