@@ -8512,6 +8512,12 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc)
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) {
@@ -8529,6 +8535,12 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc)
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) {
@@ -8820,6 +8832,11 @@ _base_check_ioc_facts_changes(struct MPT3SAS_ADAPTER *ioc)
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) {
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@gmail.com/ Fixes: c696f7b83ede ("scsi: mpt3sas: Implement device_remove_in_progress check in IOCTL path") Cc: stable@vger.kernel.org Suggested-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> --- Changelog: v2: * Do the same protection in krealloc() in _base_check_ioc_facts_changes, as suggested by Keith. --- drivers/scsi/mpt3sas/mpt3sas_base.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)