sysfs/bin: Fix size handling overflow for bin_attribute

While looking at the code, I noticed that bin_attribute read() and write()
ops copy the inode size into an int for futher comparisons.

Some bin_attributes can be fairly large. For example, pci creates some for
BARs set to the BAR size and giant BARs are around the corner, so this is
going to break something somewhere eventually.

Let's use the right type.

[adjust for seqfile conversions, only needed for bin_read() - gkh]

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index c324ee9..5d818df 100644 (file)
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -156,7 +156,7 @@ static ssize_t sysfs_bin_read(struct file *file, char __user *userbuf,
        struct sysfs_open_file *of = sysfs_of(file);
        struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;
        struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
-       int size = file_inode(file)->i_size;
+       loff_t size = file_inode(file)->i_size;
        int count = min_t(size_t, bytes, PAGE_SIZE);
        loff_t offs = *off;
        char *buf;