| Message ID | 20240605085530.499432-1-leitao@debian.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] mpt3sas: Avoid test/set_bit() operating in non-allocated memory | expand |
On Wed, Jun 05, 2024 at 01:55:29AM -0700, Breno Leitao wrote: > 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. Looks good. Reviewed-by: Keith Busch <kbusch@kernel.org>
On Wed, 05 Jun 2024 01:55:29 -0700, Breno Leitao wrote: > 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 > > [...] Applied to 6.10/scsi-fixes, thanks! [1/1] mpt3sas: Avoid test/set_bit() operating in non-allocated memory https://git.kernel.org/mkp/scsi/c/4254dfeda82f
From: Breno Leitao <leitao@debian.org> > Sent: 05 June 2024 09:55 > > 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. > ... > @@ -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); That is entirely stupid code. IIRC there is a BITMAP_SIZE() that does ((x) + 63u) & ~63)/8 (on 64bit systems). David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c index 258647fc6bdd..cc17204721c2 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.c +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c @@ -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(+)