Commit fc3d092c authored by Michael Schmitz's avatar Michael Schmitz Committed by Jens Axboe
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block: fix signed int overflow in Amiga partition support 



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@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 3 of this series for that).

Reported-by: default avatarMartin Steigerwald <Martin@lichtvoll.de>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=43511


Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Message-ID: <201206192146.09327.Martin@lichtvoll.de>
Cc: <stable@vger.kernel.org> # 5.2
Signed-off-by: default avatarMichael Schmitz <schmitzmic@gmail.com>
Tested-by: default avatarMartin Steigerwald <Martin@lichtvoll.de>
Reviewed-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230620201725.7020-2-schmitzmic@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 6d4e80db

block/partitions/amiga.c

+5 −4
Original line number Diff line number Diff line
@@ -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 -

		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;