* Jens Axboe ([EMAIL PROTECTED]) wrote:
> On Tue, Oct 31 2006, NeilBrown wrote:
> > This would be good for 2.6.19 and even 18.2, if it is seens acceptable.
> > raid0 at least (possibly other) can be made to Oops with a bad partition 
> > table and best fix seem to be to not let out-of-range request get down
> > to the device.
> > 
> > ### Comments for Changeset
> > 
> > Partitions are not limited to live within a device.  So
> > we should range check after partition mapping.
> > 
> > Note that 'maxsector' was being used for two different things.  I have
> > split off the second usage into 'old_sector' so that maxsector can be
> > still be used for it's primary usage later in the function.
> > 
> > Cc: Jens Axboe <[EMAIL PROTECTED]>
> > Signed-off-by: Neil Brown <[EMAIL PROTECTED]>
> 
> Code looks good to me, but for some reason your comment exceeds 80
> chars. Can you please fix that up?

Maybe just was copy, pasted and pushed one tab over from the same check
above the loop.  What about consolidating that one?

thanks,
-chris

--

From: Neil Brown <[EMAIL PROTECTED]>

Partitions are not limited to live within a device.  So
we should range check after partition mapping.
                                                                                
                                   
Note that 'maxsector' was being used for two different things.  I have
split off the second usage into 'old_sector' so that maxsector can be
still be used for it's primary usage later in the function.
                                                                                
                                   
Acked-by: Jens Axboe <[EMAIL PROTECTED]>
Signed-off-by: Neil Brown <[EMAIL PROTECTED]>

Add check_bad_sector() to consolidate the checks a touch.

Signed-off-by: Chris Wright <[EMAIL PROTECTED]>

---
(smth like this only compile tested extension to Neil's patch)

 block/ll_rw_blk.c |   51 +++++++++++++++++++++++++++++++--------------------
 1 file changed, 31 insertions(+), 20 deletions(-)

--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -2971,6 +2971,26 @@ static void handle_bad_sector(struct bio
        set_bit(BIO_EOF, &bio->bi_flags);
 }
 
+static int check_bad_sector(struct bio *bio)
+{
+       sector_t maxsector = bio->bi_bdev->bd_inode->i_size >> 9;
+       int nr_sectors = bio_sectors(bio);
+       if (maxsector) {
+               sector_t sector = bio->bi_sector;
+
+               if (maxsector < nr_sectors || maxsector - nr_sectors < sector) {
+                       /*
+                        * This may well happen - the kernel calls bread()
+                        * without checking the size of the device, e.g., when
+                        * mounting a device.
+                        */
+                       handle_bad_sector(bio);
+                       return 1;
+               }
+       }
+       return 0;
+}
+
 /**
  * generic_make_request: hand a buffer to its device driver for I/O
  * @bio:  The bio describing the location in memory and on the device.
@@ -2998,26 +3018,14 @@ static void handle_bad_sector(struct bio
 void generic_make_request(struct bio *bio)
 {
        request_queue_t *q;
-       sector_t maxsector;
-       int ret, nr_sectors = bio_sectors(bio);
+       sector_t old_sector;
+       int ret;
        dev_t old_dev;
 
        might_sleep();
        /* Test device or partition size, when known. */
-       maxsector = bio->bi_bdev->bd_inode->i_size >> 9;
-       if (maxsector) {
-               sector_t sector = bio->bi_sector;
-
-               if (maxsector < nr_sectors || maxsector - nr_sectors < sector) {
-                       /*
-                        * This may well happen - the kernel calls bread()
-                        * without checking the size of the device, e.g., when
-                        * mounting a device.
-                        */
-                       handle_bad_sector(bio);
-                       goto end_io;
-               }
-       }
+       if (check_bad_sector(bio))
+               goto end_io;
 
        /*
         * Resolve the mapping until finished. (drivers are
@@ -3027,7 +3035,7 @@ void generic_make_request(struct bio *bi
         * NOTE: we don't repeat the blk_size check for each new device.
         * Stacking drivers are expected to know what they are doing.
         */
-       maxsector = -1;
+       old_sector = -1;
        old_dev = 0;
        do {
                char b[BDEVNAME_SIZE];
@@ -3061,15 +3069,18 @@ end_io:
                 */
                blk_partition_remap(bio);
 
-               if (maxsector != -1)
+               if (old_sector != -1)
                        blk_add_trace_remap(q, bio, old_dev, bio->bi_sector, 
-                                           maxsector);
+                                           old_sector);
 
                blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
 
-               maxsector = bio->bi_sector;
+               old_sector = bio->bi_sector;
                old_dev = bio->bi_bdev->bd_dev;
 
+               if (check_bad_sector(bio))
+                       goto end_io;
+
                ret = q->make_request_fn(q, bio);
        } while (ret);
 }
-
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