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t=1660659194; a=rsa-sha256; cv=fail; b=A91qDo3H46bx+szzJBWuEhYoebPqLzpZqdkbF/boymHkcRO4n6CBt7epdNSdlsh+h2UoAq c8VIiHWZWQ8bbIvpish1Tvy2jDiBpdLjge1XauHSLK9Fl6ofOrhmyl3fiqXYyI0RBuiKiU +Dp9Sshg8FizBxUbGLYennOo5sn7B5Q= X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 945B9201CD X-Rspam-User: Authentication-Results: imf13.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=mlol1aS0; spf=pass (imf13.hostedemail.com: domain of feng.tang@intel.com designates 192.55.52.151 as permitted sender) smtp.mailfrom=feng.tang@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); dmarc=pass (policy=none) header.from=intel.com X-Stat-Signature: 8gauyig56drxk969cxim6a6n6frh1s9a X-HE-Tag: 1660659193-866123 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Aug 16, 2022 at 09:27:39PM +0800, Sang, Oliver wrote: > Hi Feng, > > On Mon, Aug 15, 2022 at 03:27:43PM +0800, Feng Tang wrote: > > Hi Oliver, > > > > Could you help to check if the below combined patch fix the problem > > you reported? thanks! > > I applied below patch upon 3616799128: > 28b34693c816e9 (linux-devel/fixup-3616799128) fix for 3616799128: BUG_kmalloc-#(Not_tainted):kmalloc_Redzone_overwritten > 3616799128612e (linux-review/Feng-Tang/mm-slub-some-debug-enhancements/20220727-151318) mm/slub: extend redzone check to cover extra allocated kmalloc space than requested > acc77d62f91ccc mm/slub: only zero the requested size of buffer for kzalloc > > > confirmed the issue gone: Many thanks for helping testing! - Feng > ========================================================================================= > compiler/kconfig/rootfs/sleep/tbox_group/testcase: > gcc-11/x86_64-randconfig-a005-20220117/debian-11.1-x86_64-20220510.cgz/300/vm-snb/boot > > > acc77d62f91ccca2 3616799128612e04ed919579e2c 28b34693c816e9fcbe42bdd341e > ---------------- --------------------------- --------------------------- > fail:runs %reproduction fail:runs %reproduction fail:runs > | | | | | > :20 95% 19:20 0% :22 dmesg.BUG_kmalloc-#(Not_tainted):kmalloc_Redzone_overwritten > :20 95% 19:20 0% :22 dmesg.BUG_kmalloc-#(Tainted:G_B):kmalloc_Redzone_overwritten > > > > > > > - Feng > > > > --- > > > > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > > index b092277bf48d6..293bdaa0ba09c 100644 > > --- a/include/linux/kasan.h > > +++ b/include/linux/kasan.h > > @@ -100,6 +100,8 @@ static inline bool kasan_has_integrated_init(void) > > struct kasan_cache { > > int alloc_meta_offset; > > int free_meta_offset; > > + /* size of free_meta data saved in object's data area */ > > + int free_meta_size_in_object; > > bool is_kmalloc; > > }; > > > > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > > index c40c0e7b3b5f1..9d2994dbe4e7a 100644 > > --- a/mm/kasan/common.c > > +++ b/mm/kasan/common.c > > @@ -200,6 +200,8 @@ void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size, > > cache->kasan_info.free_meta_offset = KASAN_NO_FREE_META; > > *size = ok_size; > > } > > + } else { > > + cache->kasan_info.free_meta_size_in_object = sizeof(struct kasan_free_meta); > > } > > > > /* Calculate size with optimal redzone. */ > > diff --git a/mm/slub.c b/mm/slub.c > > index added2653bb03..272dcdbaaa03b 100644 > > --- a/mm/slub.c > > +++ b/mm/slub.c > > @@ -830,6 +830,16 @@ static inline void set_orig_size(struct kmem_cache *s, > > if (!slub_debug_orig_size(s)) > > return; > > > > +#ifdef CONFIG_KASAN_GENERIC > > + /* > > + * kasn could save its free meta data in the start part of object > > + * area, so skip the redzone check if kasan's meta data size is > > + * bigger enough to possibly overlap with kmalloc redzone > > + */ > > + if (s->kasan_info.free_meta_size_in_object * 2 > s->object_size) > > + orig_size = s->object_size; > > +#endif > > + > > p += get_info_end(s); > > p += sizeof(struct track) * 2; > >