The Amiga partition parser module uses signed int for partition sector
address and count, which will overflow for disks larger than 1 TB.
Use sector_t as type for sector address and size to allow using disks
up to 2 TB without LBD support, and disks larger than 2 TB with LBD.
This bug was reported originally in 2012, and the fix was created by
the RDB author, Joanne Dow <jdow(a)earthlink.net>. A patch had been
discussed and reviewed on linux-m68k at that time but never officially
submitted. This patch differs from Joanne's patch only in its use of
sector_t instead of unsigned int. No checking for overflows is done
(see patch 2 of this series for that).
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=43511
Fixes: 1da177e4c3f41524 ("Linux-2.6.12-rc2")
Cc: <stable(a)vger.kernel.org> # 5.2
Reported-by: Martin Steigerwald <Martin(a)lichtvoll.de>
Message-ID: <201206192146.09327.Martin(a)lichtvoll.de>
Signed-off-by: Michael Schmitz <schmitzmic(a)gmail.com>
Tested-by: Martin Steigerwald <Martin(a)lichtvoll.de>
Reviewed-by: Geert Uytterhoeven <geert(a)linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
---
Changes from v3:
- split off change of sector address type as quick fix.
- cast to sector_t in sector address calculations.
- move overflow checking to separate patch for more thorough review.
Changes from v4:
Andreas Schwab:
- correct cast to sector_t in sector address calculations
Changes from v7:
Christoph Hellwig
- correct style issues
---
block/partitions/amiga.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/block/partitions/amiga.c b/block/partitions/amiga.c
index 5c8624e26a54..85c5c79aae48 100644
--- a/block/partitions/amiga.c
+++ b/block/partitions/amiga.c
@@ -31,7 +31,8 @@ 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;
@@ -96,14 +97,14 @@ int amiga_partition(struct parsed_partitions *state)
/* Tell Kernel about it */
- nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
- be32_to_cpu(pb->pb_Environment[9])) *
+ nr_sects = ((sector_t)be32_to_cpu(pb->pb_Environment[10]) + 1 -
+ be32_to_cpu(pb->pb_Environment[9])) *
be32_to_cpu(pb->pb_Environment[3]) *
be32_to_cpu(pb->pb_Environment[5]) *
blksize;
if (!nr_sects)
continue;
- start_sect = be32_to_cpu(pb->pb_Environment[9]) *
+ start_sect = (sector_t)be32_to_cpu(pb->pb_Environment[9]) *
be32_to_cpu(pb->pb_Environment[3]) *
be32_to_cpu(pb->pb_Environment[5]) *
blksize;
--
2.17.1