From: Breno Leitao <leitao@xxxxxxxxxx> commit 4254dfeda82f20844299dca6c38cbffcfd499f41 upstream. There is a potential out-of-bounds access when using test_bit() on a single word. The test_bit() and set_bit() functions operate on long values, and when testing or setting a single word, they can exceed the word boundary. KASAN detects this issue and produces a dump: BUG: KASAN: slab-out-of-bounds in _scsih_add_device.constprop.0 (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 drivers/scsi/mpt3sas/mpt3sas_scsih.c:7331) mpt3sas Write of size 8 at addr ffff8881d26e3c60 by task kworker/u1536:2/2965 For full log, please look at [1]. Make the allocation at least the size of sizeof(unsigned long) so that set_bit() and test_bit() have sufficient room for read/write operations without overwriting unallocated memory. [1] Link: https://lore.kernel.org/all/ZkNcALr3W3KGYYJG@xxxxxxxxx/ Fixes: c696f7b83ede ("scsi: mpt3sas: Implement device_remove_in_progress check in IOCTL path") Cc: stable@xxxxxxxxxxxxxxx Suggested-by: Keith Busch <kbusch@xxxxxxxxxx> Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240605085530.499432-1-leitao@xxxxxxxxxx Reviewed-by: Keith Busch <kbusch@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/mpt3sas/mpt3sas_base.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/drivers/scsi/mpt3sas/mpt3sas_base.c +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c @@ -7089,6 +7089,12 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPT ioc->pd_handles_sz = (ioc->facts.MaxDevHandle / 8); if (ioc->facts.MaxDevHandle % 8) ioc->pd_handles_sz++; + /* + * pd_handles_sz should have, at least, the minimal room for + * set_bit()/test_bit(), otherwise out-of-memory touch may occur. + */ + ioc->pd_handles_sz = ALIGN(ioc->pd_handles_sz, sizeof(unsigned long)); + ioc->pd_handles = kzalloc(ioc->pd_handles_sz, GFP_KERNEL); if (!ioc->pd_handles) { @@ -7106,6 +7112,13 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPT ioc->pend_os_device_add_sz = (ioc->facts.MaxDevHandle / 8); if (ioc->facts.MaxDevHandle % 8) ioc->pend_os_device_add_sz++; + + /* + * pend_os_device_add_sz should have, at least, the minimal room for + * set_bit()/test_bit(), otherwise out-of-memory may occur. + */ + ioc->pend_os_device_add_sz = ALIGN(ioc->pend_os_device_add_sz, + sizeof(unsigned long)); ioc->pend_os_device_add = kzalloc(ioc->pend_os_device_add_sz, GFP_KERNEL); if (!ioc->pend_os_device_add) { @@ -7384,6 +7397,12 @@ _base_check_ioc_facts_changes(struct MPT if (ioc->facts.MaxDevHandle % 8) pd_handles_sz++; + /* + * pd_handles should have, at least, the minimal room for + * set_bit()/test_bit(), otherwise out-of-memory touch may + * occur. + */ + pd_handles_sz = ALIGN(pd_handles_sz, sizeof(unsigned long)); pd_handles = krealloc(ioc->pd_handles, pd_handles_sz, GFP_KERNEL); if (!pd_handles) { Patches currently in stable-queue which might be from leitao@xxxxxxxxxx are queue-5.4/scsi-mpt3sas-avoid-test-set_bit-operating-in-non-allocated-memory.patch