>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 <mar...@lichtvoll.de>, and the fix was created by the RDB author, Joanne Dow <j...@earthlink.net>. 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 <mar...@lichtvoll.de> Message-ID: <201206192146.09327.mar...@lichtvoll.de> Signed-off-by: Michael Schmitz <schmitz...@gmail.com> Tested-by: Martin Steigerwald <mar...@lichtvoll.de> Tested-by: Michael Schmitz <schmitz...@gmail.com> --- 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)); + } put_partition(state,slot++,start_sect,nr_sects); { /* Be even more informative to aid mounting */ -- 1.9.1