[XFS] Fix a 32 bit value wraparound when providing a mapping for a large
direct write.
SGI-PV: 944820
SGI-Modid: xfs-linux-melb:xfs-kern:24351a
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index c610897..94d3cdf 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -941,13 +941,12 @@
int retpbbm = 1;
int error;
- if (blocks) {
- offset = blocks << inode->i_blkbits; /* 64 bit goodness */
- size = (ssize_t) min_t(xfs_off_t, offset, LONG_MAX);
- } else {
- size = 1 << inode->i_blkbits;
- }
offset = (xfs_off_t)iblock << inode->i_blkbits;
+ if (blocks)
+ size = (ssize_t) min_t(xfs_off_t, LONG_MAX,
+ (xfs_off_t)blocks << inode->i_blkbits);
+ else
+ size = 1 << inode->i_blkbits;
VOP_BMAP(vp, offset, size,
create ? flags : BMAPI_READ, &iomap, &retpbbm, error);
@@ -1007,7 +1006,7 @@
ASSERT(iomap.iomap_bsize - iomap.iomap_delta > 0);
offset = min_t(xfs_off_t,
iomap.iomap_bsize - iomap.iomap_delta,
- blocks << inode->i_blkbits);
+ (xfs_off_t)blocks << inode->i_blkbits);
bh_result->b_size = (u32) min_t(xfs_off_t, UINT_MAX, offset);
}