Bodo Stroesser ff876b6cf5 scsi: target: tcmu: Avoid holding XArray lock when calling lock_page ...

[ Upstream commit 325d5c5fb2 ]

In tcmu_blocks_release(), lock_page() is called to prevent a race causing
possible data corruption. Since lock_page() might sleep, calling it while
holding XArray lock is a bug.

To fix this, replace the xas_for_each() call with xa_for_each_range().
Since the latter does its own handling of XArray locking, the xas_lock()
and xas_unlock() calls around the original loop are no longer necessary.

The switch to xa_for_each_range() slows down the loop slightly. This is
acceptable since tcmu_blocks_release() is not relevant for performance.

Link: https://lore.kernel.org/r/20220517192913.21405-1-bostroesser@gmail.com
Fixes: bb9b9eb0ae ("scsi: target: tcmu: Fix possible data corruption")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bodo Stroesser <bostroesser@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2022-06-09 10:22:40 +02:00

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iscsi

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loopback

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sbp

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tcm_fc

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Kconfig

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Makefile

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target_core_alua.c

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target_core_alua.h

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target_core_configfs.c

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target_core_device.c

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target_core_fabric_configfs.c

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target_core_fabric_lib.c

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target_core_file.c

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target_core_file.h

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target_core_hba.c

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target_core_iblock.c

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target_core_iblock.h

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target_core_internal.h

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target_core_pr.c

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target_core_pr.h

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target_core_pscsi.c

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target_core_pscsi.h

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target_core_rd.c

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target_core_rd.h

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target_core_sbc.c

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target_core_spc.c

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target_core_stat.c

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target_core_tmr.c

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target_core_tpg.c

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target_core_transport.c

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target_core_ua.c

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target_core_ua.h

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target_core_user.c

scsi: target: tcmu: Avoid holding XArray lock when calling lock_page

2022-06-09 10:22:40 +02:00

target_core_xcopy.c

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target_core_xcopy.h

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