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 <[email protected]>. 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 Reported-by: Martin Steigerwald <[email protected]> Message-ID: <[email protected]> Signed-off-by: Michael Schmitz <[email protected]> Tested-by: Martin Steigerwald <[email protected]> Reviewed-by: Geert Uytterhoeven <[email protected]> --- 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 --- 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 5609366..7ea9540 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]; @@ -100,14 +101,14 @@ 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; -- 1.9.1
