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| author | Vasily Gorbik <gor@linux.ibm.com> | 2019-09-17 22:59:03 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2019-12-10 18:01:23 +0000 |
| commit | 846903f2d25e290cf01b78e884d7ba031703ee32 (patch) | |
| tree | a854c73a6d3c1ec81d37a9063cfde50981e20a82 /arch/s390/kernel | |
| parent | 183fb1de1665e1d6eea989414dea657caf75e474 (diff) | |
| download | linux-stable-846903f2d25e290cf01b78e884d7ba031703ee32.tar.gz linux-stable-846903f2d25e290cf01b78e884d7ba031703ee32.tar.bz2 linux-stable-846903f2d25e290cf01b78e884d7ba031703ee32.zip | |
s390/topology: avoid firing events before kobjs are created
commit f3122a79a1b0a113d3aea748e0ec26f2cb2889de upstream.
arch_update_cpu_topology is first called from:
kernel_init_freeable->sched_init_smp->sched_init_domains
even before cpus has been registered in:
kernel_init_freeable->do_one_initcall->s390_smp_init
Do not trigger kobject_uevent change events until cpu devices are
actually created. Fixes the following kasan findings:
BUG: KASAN: global-out-of-bounds in kobject_uevent_env+0xb40/0xee0
Read of size 8 at addr 0000000000000020 by task swapper/0/1
BUG: KASAN: global-out-of-bounds in kobject_uevent_env+0xb36/0xee0
Read of size 8 at addr 0000000000000018 by task swapper/0/1
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G B
Hardware name: IBM 3906 M04 704 (LPAR)
Call Trace:
([<0000000143c6db7e>] show_stack+0x14e/0x1a8)
[<0000000145956498>] dump_stack+0x1d0/0x218
[<000000014429fb4c>] print_address_description+0x64/0x380
[<000000014429f630>] __kasan_report+0x138/0x168
[<0000000145960b96>] kobject_uevent_env+0xb36/0xee0
[<0000000143c7c47c>] arch_update_cpu_topology+0x104/0x108
[<0000000143df9e22>] sched_init_domains+0x62/0xe8
[<000000014644c94a>] sched_init_smp+0x3a/0xc0
[<0000000146433a20>] kernel_init_freeable+0x558/0x958
[<000000014599002a>] kernel_init+0x22/0x160
[<00000001459a71d4>] ret_from_fork+0x28/0x30
[<00000001459a71dc>] kernel_thread_starter+0x0/0x10
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch/s390/kernel')
| -rw-r--r-- | arch/s390/kernel/topology.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index b93bed76ea94..404a1119fd65 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -266,7 +266,8 @@ int arch_update_cpu_topology(void) update_cpu_masks(); for_each_online_cpu(cpu) { dev = get_cpu_device(cpu); - kobject_uevent(&dev->kobj, KOBJ_CHANGE); + if (dev) + kobject_uevent(&dev->kobj, KOBJ_CHANGE); } return 1; } |