Wang Cheng ddb3f0b688 mm/mempolicy: fix uninit-value in mpol_rebind_policy() ... commit 018160ad31 upstream. mpol_set_nodemask()(mm/mempolicy.c) does not set up nodemask when pol->mode is MPOL_LOCAL. Check pol->mode before access pol->w.cpuset_mems_allowed in mpol_rebind_policy()(mm/mempolicy.c). BUG: KMSAN: uninit-value in mpol_rebind_policy mm/mempolicy.c:352 [inline] BUG: KMSAN: uninit-value in mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 mpol_rebind_policy mm/mempolicy.c:352 [inline] mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 cpuset_change_task_nodemask kernel/cgroup/cpuset.c:1711 [inline] cpuset_attach+0x787/0x15e0 kernel/cgroup/cpuset.c:2278 cgroup_migrate_execute+0x1023/0x1d20 kernel/cgroup/cgroup.c:2515 cgroup_migrate kernel/cgroup/cgroup.c:2771 [inline] cgroup_attach_task+0x540/0x8b0 kernel/cgroup/cgroup.c:2804 __cgroup1_procs_write+0x5cc/0x7a0 kernel/cgroup/cgroup-v1.c:520 cgroup1_tasks_write+0x94/0xb0 kernel/cgroup/cgroup-v1.c:539 cgroup_file_write+0x4c2/0x9e0 kernel/cgroup/cgroup.c:3852 kernfs_fop_write_iter+0x66a/0x9f0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2162 [inline] new_sync_write fs/read_write.c:503 [inline] vfs_write+0x1318/0x2030 fs/read_write.c:590 ksys_write+0x28b/0x510 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0xdb/0x120 fs/read_write.c:652 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0x902/0x11c0 mm/slub.c:3264 mpol_new mm/mempolicy.c:293 [inline] do_set_mempolicy+0x421/0xb70 mm/mempolicy.c:853 kernel_set_mempolicy mm/mempolicy.c:1504 [inline] __do_sys_set_mempolicy mm/mempolicy.c:1510 [inline] __se_sys_set_mempolicy+0x44c/0xb60 mm/mempolicy.c:1507 __x64_sys_set_mempolicy+0xd8/0x110 mm/mempolicy.c:1507 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae KMSAN: uninit-value in mpol_rebind_task (2) https://syzkaller.appspot.com/bug?id=d6eb90f952c2a5de9ea718a1b873c55cb13b59dc This patch seems to fix below bug too. KMSAN: uninit-value in mpol_rebind_mm (2) https://syzkaller.appspot.com/bug?id=f2fecd0d7013f54ec4162f60743a2b28df40926b The uninit-value is pol->w.cpuset_mems_allowed in mpol_rebind_policy(). When syzkaller reproducer runs to the beginning of mpol_new(), mpol_new() mm/mempolicy.c do_mbind() mm/mempolicy.c kernel_mbind() mm/mempolicy.c `mode` is 1(MPOL_PREFERRED), nodes_empty(*nodes) is `true` and `flags` is 0. Then mode = MPOL_LOCAL; ... policy->mode = mode; policy->flags = flags; will be executed. So in mpol_set_nodemask(), mpol_set_nodemask() mm/mempolicy.c do_mbind() kernel_mbind() pol->mode is 4 (MPOL_LOCAL), that `nodemask` in `pol` is not initialized, which will be accessed in mpol_rebind_policy(). Link: https://lkml.kernel.org/r/20220512123428.fq3wofedp6oiotd4@ppc.localdomain Signed-off-by: Wang Cheng <wanngchenng@gmail.com> Reported-by: <syzbot+217f792c92599518a2ab@syzkaller.appspotmail.com> Tested-by: <syzbot+217f792c92599518a2ab@syzkaller.appspotmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-07-29 17:19:23 +02:00
..
kasan	kasan: prevent cpu_quarantine corruption when CPU offline and cache shrink occur at same time	2022-05-09 09:05:07 +02:00
backing-dev.c
balloon_compaction.c
cleancache.c
cma_debug.c
cma.c
cma.h
compaction.c	mm, compaction: fast_find_migrateblock() should return pfn in the target zone	2022-06-09 10:21:23 +02:00
debug_page_ref.c
debug_vm_pgtable.c
debug.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c
frame_vector.c
frontswap.c
gup_benchmark.c
gup.c
highmem.c
hmm.c
huge_memory.c
hugetlb_cgroup.c
hugetlb.c	hugetlb: fix huge_pmd_unshare address update	2022-06-09 10:21:27 +02:00
hwpoison-inject.c
init-mm.c
internal.h
interval_tree.c
ioremap.c
Kconfig
Kconfig.debug
khugepaged.c
kmemleak.c	mm: kmemleak: take a full lowmem check in kmemleak_*_phys()	2022-04-20 09:23:25 +02:00
ksm.c
list_lru.c
maccess.c
madvise.c	Revert "mm: madvise: skip unmapped vma holes passed to process_madvise"	2022-04-08 14:39:54 +02:00
Makefile
mapping_dirty_helpers.c
memblock.c
memcontrol.c	mm/memcontrol: return 1 from cgroup.memory __setup() handler	2022-04-08 14:40:43 +02:00
memfd.c	memfd: fix F_SEAL_WRITE after shmem huge page allocated	2022-03-08 19:09:36 +01:00
memory_hotplug.c
memory-failure.c
memory.c	mm: split huge PUD on wp_huge_pud fallback	2022-07-21 21:19:59 +02:00
mempolicy.c	mm/mempolicy: fix uninit-value in mpol_rebind_policy()	2022-07-29 17:19:23 +02:00
mempool.c
memremap.c
memtest.c
migrate.c	mm: fix missing cache flush for all tail pages of compound page	2022-05-15 20:00:09 +02:00
mincore.c
mlock.c
mm_init.c
mmap.c	mm, hugetlb: allow for "high" userspace addresses	2022-04-27 13:53:54 +02:00
mmu_gather.c
mmu_notifier.c	mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()	2022-04-27 13:53:54 +02:00
mmzone.c	arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL	2022-05-15 20:00:09 +02:00
mprotect.c
mremap.c	mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0)	2022-04-13 21:01:08 +02:00
msync.c
nommu.c
oom_kill.c	oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup	2022-04-27 13:53:54 +02:00
page_alloc.c	mm: page_alloc: fix building error on -Werror=array-compare	2022-04-27 13:53:45 +02:00
page_counter.c
page_ext.c
page_idle.c
page_io.c	mm: fix unexpected zeroed page mapping with zram swap	2022-04-20 09:23:25 +02:00
page_isolation.c
page_owner.c
page_poison.c
page_reporting.c
page_reporting.h
page_vma_mapped.c
page-writeback.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgalloc-track.h
pgtable-generic.c
process_vm_access.c
ptdump.c
readahead.c
rmap.c	mm: fix race between MADV_FREE reclaim and blkdev direct IO read	2022-04-13 21:01:03 +02:00
rodata_test.c
shmem.c
shuffle.c
shuffle.h
slab_common.c
slab.c
slab.h
slob.c
slub.c	mm/slub: add missing TID updates on slab deactivation	2022-07-12 16:32:16 +02:00
sparse-vmemmap.c
sparse.c
swap_cgroup.c
swap_slots.c
swap_state.c	mm: swap: get rid of livelock in swapin readahead	2022-03-23 09:13:27 +01:00
swap.c
swapfile.c
truncate.c
usercopy.c	mm/usercopy: return 1 from hardened_usercopy __setup() handler	2022-04-08 14:40:43 +02:00
userfaultfd.c	mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic()	2022-05-15 20:00:09 +02:00
util.c	random: move randomize_page() into mm where it belongs	2022-05-30 09:33:45 +02:00
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c
vmstat.c	arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL	2022-05-15 20:00:09 +02:00
workingset.c
z3fold.c
zbud.c
zpool.c
zsmalloc.c	zsmalloc: fix races between asynchronous zspage free and page migration	2022-06-06 08:42:43 +02:00
zswap.c