Darrick J. Wong 9471744767 bcache: fix BUG_ON due to integer overflow with GC_SECTORS_USED ... The BUG_ON at the end of __bch_btree_mark_key can be triggered due to an integer overflow error: BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 13); ... SET_GC_SECTORS_USED(g, min_t(unsigned, GC_SECTORS_USED(g) + KEY_SIZE(k), (1 << 14) - 1)); BUG_ON(!GC_SECTORS_USED(g)); In bcache.h, the SECTORS_USED bitfield is defined to be 13 bits wide. While the SET_ code tries to ensure that the field doesn't overflow by clamping it to (1<<14)-1 == 16383, this is incorrect because 16383 requires 14 bits. Therefore, if GC_SECTORS_USED() + KEY_SIZE() = 8192, the SET_ statement tries to store 8192 into a 13-bit field. In a 13-bit field, 8192 becomes zero, thus triggering the BUG_ON. Therefore, create a field width constant and a max value constant, and use those to create the bitfield and check the inputs to SET_GC_SECTORS_USED. Arguably the BITMASK() template ought to have BUG_ON checks for too-large values, but that's a separate patch. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>		2014-01-29 13:06:15 -08:00
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bcache	bcache: fix BUG_ON due to integer overflow with GC_SECTORS_USED	2014-01-29 13:06:15 -08:00
persistent-data
bitmap.c
bitmap.h
dm-bio-prison.c
dm-bio-prison.h
dm-bio-record.h
dm-bufio.c
dm-bufio.h
dm-cache-block-types.h
dm-cache-metadata.c
dm-cache-metadata.h
dm-cache-policy-cleaner.c
dm-cache-policy-internal.h
dm-cache-policy-mq.c
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c
dm-crypt.c
dm-delay.c
dm-exception-store.c
dm-exception-store.h
dm-flakey.c
dm-io.c
dm-ioctl.c
dm-kcopyd.c
dm-linear.c
dm-log-userspace-base.c
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log.c
dm-mpath.c
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid1.c
dm-raid.c
dm-region-hash.c
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c
dm-snap-transient.c
dm-snap.c
dm-stats.c
dm-stats.h
dm-stripe.c
dm-switch.c
dm-sysfs.c
dm-table.c
dm-target.c
dm-thin-metadata.c
dm-thin-metadata.h
dm-thin.c
dm-uevent.c
dm-uevent.h
dm-verity.c
dm-zero.c
dm.c
dm.h
faulty.c
Kconfig
linear.c
linear.h
Makefile
md.c
md.h
multipath.c
multipath.h
raid0.c
raid0.h
raid1.c
raid1.h
raid5.c	bcache/md: Use raid stripe size	2014-01-08 13:05:09 -08:00
raid5.h
raid10.c
raid10.h