schmitzmic@xxxxxxxxx - 27.06.18, 03:24:
From 5299e0e64dfb33ac3a1f3137b42178734ce20087 Mon Sep 17 00:00:00 2001
The Amiga RDB partition parser module uses int for partition sector
address and count, which will overflow for disks 2 TB and larger.
Use sector_t as type for sector address and size (as expected by
put_partition) to allow using such disks without danger of data
corruption.
This bug was reported originally in 2012 by Martin Steigerwald
<Martin@xxxxxxxxxxxx>, and the fix was created by the RDB author,
Joanne Dow <jdow@xxxxxxxxxxxxx>. The patch had been discussed and
reviewed on linux-m68k at that time but never officially submitted.
Following a stern warning by Joanne, a warning is printed if any
partition is found to overflow the old 32 bit calculations, on the
grounds that such a partition would be misparses on legacy 32 bit
systems (other than Linux).
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=43511
Reported-by: Martin Steigerwald <Martin@xxxxxxxxxxxx>
Message-ID: <201206192146.09327.Martin@xxxxxxxxxxxx>
Signed-off-by: Michael Schmitz <schmitzmic@xxxxxxxxx>
Tested-by: Martin Steigerwald <Martin@xxxxxxxxxxxx>
Tested-by: Michael Schmitz <schmitzmic@xxxxxxxxx>
---
block/partitions/amiga.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/block/partitions/amiga.c b/block/partitions/amiga.c
index 5609366..42c3f38 100644
--- a/block/partitions/amiga.c
+++ b/block/partitions/amiga.c
@@ -32,7 +32,8 @@ int amiga_partition(struct parsed_partitions *state)
unsigned char *data;
struct RigidDiskBlock *rdb;
struct PartitionBlock *pb;
- int start_sect, nr_sects, blk, part, res = 0;
+ sector_t start_sect, nr_sects;
+ int blk, part, res = 0;
int blksize = 1; /* Multiplier for disk block size */
int slot = 1;
char b[BDEVNAME_SIZE];
@@ -111,6 +112,16 @@ int amiga_partition(struct parsed_partitions
*state) be32_to_cpu(pb->pb_Environment[3]) *
be32_to_cpu(pb->pb_Environment[5]) *
blksize;
+ if (start_sect > INT_MAX || nr_sects > INT_MAX
+ || (start_sect + nr_sects) > INT_MAX) {
+ pr_err("%s: Warning: RDB partition overflow!\n",
+ bdevname(state->bdev, b));
+ pr_err("%s: start 0x%llX size 0x%llX\n",
+ bdevname(state->bdev, b), start_sect,
+ nr_sects);
+ pr_err("%s: partition incompatible with 32 bit OS\n",
+ bdevname(state->bdev, b));
+ }
I do think the wording of that warning is inaccurate, as outlined in my
other mails in thread "Re: moving affs + RDB partition support to
staging?" just a few minutes ago (see there for a more complete
reasoning). I´d word it like this:
partition needs 64 bit disk device support in AmigaOS or AmigaOS like
operating systems (NSD64, TD64 or SCSI direct)
I think I would not include any more details, and let Amiga people
research what they need and since when it is included officially on
their own. As there are at least three variants out there: AmigaOS,
MorphOS, AROS.
AmigaOS 4 at least can handle disks of 2 TB size or more. I do not think
the wording "RDB overflow" is right either.
http://wiki.amigaos.net/wiki/RDB
Filesystem size limits are a different matter.
http://www.amigawiki.de/doku.php?id=de:system:filesystems_limits
put_partition(state,slot++,start_sect,nr_sects);
{
/* Be even more informative to aid mounting */
Thanks,
--
Martin
--
To unsubscribe from this list: send the line "unsubscribe linux-m68k" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
