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AJvYcCWsqFAlGDdjm9v5E4iSwyD3yK/leTykWCX2w3lsetFVfWHG7rjRJntsqfxla/GoST3eCZdf2DGnyA==@kvack.org X-Gm-Message-State: AOJu0YztP9f5vDzODrgbJjh6GB9Dt9+N+gzgvPgIl4rUA/RRjAMY4Itt Snjy5Y/NwhGN/i+BRE6DsbmPd8+z13ASr/REWlnnl2rsqJIoNH5vtZ59B3nuN45f9Amxza+Bx9P cupCQSioZjwiiXaEG3SrtfztaPJfNcXT38ZeCfoRpkwz/mJyxKgR5 X-Gm-Gg: ASbGncsZBGDWmo4rNfLCp/VTMEN///nitlsP7JBAHnAClw2xhLcvM5nfs1b010+6Olt oeOE7q3SbI5Lzv8srtfhJLqmYmUxJLqejjg8= X-Google-Smtp-Source: AGHT+IEOrUqXNPByor6nvuTG3gz5lYs8Ewdc+uxonPPqFwx/aZ7kOMTSliTmtp8cD50eBeoq2CGPNDR1C3g6X7pSdOk= X-Received: by 2002:a05:6214:428c:b0:6d8:7a85:59ca with SMTP id 6a1803df08f44-6dd2360e187mr4977436d6.16.1734642290278; Thu, 19 Dec 2024 13:04:50 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Yosry Ahmed Date: Thu, 19 Dec 2024 13:04:13 -0800 X-Gm-Features: AbW1kvYVCcv6y76__ZzPAc9cqCrJ3C_DctKnFgk99qiOx-hS4JEkPbgLiJtjPCI Message-ID: Subject: Re: [Bug] KASAN: slab-use-after-free Read in zswap_decompress To: Sam Sun Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, akpm@linux-foundation.org, chengming.zhou@linux.dev, Nhat Pham , hannes@cmpxchg.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: 1ozphmu9t7h9jhndtoemfg6h8fcditu1 X-Rspamd-Queue-Id: CCD3740008 X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1734642240-290512 X-HE-Meta: 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 grDR8qDX /UoA3jfx4WDHGX30zlLOc5IyAxsMsaunY0hQr3Qg99rvB69/kxJpLPWdqpMCF82o5oSQps4jNH9fp/2j5Qo9IrnQ2+b+BFVjoKhiwjZSFcNMb/u67O0gYwinlXWRmFXyZqc5Nkjbn8IiDl9szJZXMkGvaEjW0KijoEdXc0cNd2D2iufgz4kMJgZtAOuk3NT576ctGWRurU63dEgYRKNWUWf1fd0HyuuQc42dL+f0kL/Pg7hi5cNBkWaK7mD80998BQxQ9RuBdDpkR6cI3ZWJQnWdtlnwalgzlenJ2/det+7yFDAXhxE3REhTGte206m+BoQHZOLUo/uYliyssCX9E9CpZI6o91DXnao/GJhX91+gRc7bQVvFuqfTFGwu+OzpYAlr6kuzBc+RXHYIebgYdnIyymBi8X1PDi/5R0Gpa/bvugSM= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000239, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Dec 18, 2024 at 1:17=E2=80=AFAM Sam Sun w= rote: > > On Wed, Dec 18, 2024 at 3:32=E2=80=AFAM Yosry Ahmed wrote: > > > > On Tue, Dec 17, 2024 at 8:30=E2=80=AFAM Yosry Ahmed wrote: > > > > > > On Tue, Dec 17, 2024 at 2:52=E2=80=AFAM Sam Sun wrote: > > > > > > > > Dear developers and maintainers, > > > > > > > > We encountered a slab-use-after-free bug while using our modified > > > > syzkaller. Kernel crash log is listed below. > > > > > > > > > Thanks for reporting this! > > > > > > This seems to be the problem that Johannes pointed out in: > > > https://lore.kernel.org/lkml/20241113213007.GB1564047@cmpxchg.org/. > > > > > > Would you be able to check if the following diff fixes the problem? > > > > I sent a poached semi-staged git diff, apologies. Please try the > > proper patch attached instead. > > > > I am sorry that I don't have a PoC that can trigger this bug. But > according to your analysis, I think this patch can fix the bug > properly. I was able to reproduce this in a VM with a hacky diff that sets up the race condition: diff --git a/mm/zswap.c b/mm/zswap.c index f6316b66fb236..e5f7341948924 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -893,8 +893,18 @@ static bool zswap_compress(struct page *page, struct zswap_entry *entry, gfp_t gfp; u8 *dst; + set_cpus_allowed_ptr(current, cpumask_of(1)); + pr_info("zswap_compress(): running on CPU %d\n", smp_processor_id()= ); + acomp_ctx =3D raw_cpu_ptr(pool->acomp_ctx); + set_cpus_allowed_ptr(current, cpumask_of(0)); + pr_info("zswap_compress(): running on CPU %d\n", smp_processor_id()= ); + pr_info("zswap_compress(): sleeping\n"); + + schedule_timeout_uninterruptible(msecs_to_jiffies(10*MSEC_PER_SEC))= ; + pr_info("zswap_compress(): woke up on CPU %d\n", smp_processor_id()= ); + mutex_lock(&acomp_ctx->mutex); dst =3D acomp_ctx->buffer; Running a user program that invokes zswap compression, after "sleeping" is printed I manually offlined CPU 1 and I got a similar KASAN UAF splat and a kernel crash due to faulting on an illegal kernel address. This goes away with my fix and the offlining is delayed until the end of zswap_compress(), so I will send it out separately. > > > > > > > > > diff --git a/mm/zswap.c b/mm/zswap.c > > > index 0030ce8fecfc5..089d70dee3246 100644 > > > --- a/mm/zswap.c > > > +++ b/mm/zswap.c > > > @@ -875,6 +875,21 @@ static int zswap_cpu_comp_dead(unsigned int cpu, > > > struct hlist_node *node) > > > return 0; > > > } > > > > > > +static void acomp_ctx_get_cpu(struct crypto_acomp_ctx *acomp_ctx) > > > +{ > > > + /* > > > + * Prevent CPU hotplug from freeing this CPU's acomp_ctx unti= l > > > + * acomp_ctx_put_cpu(). > > > + */ > > > + cpus_read_lock(); > > > + return raw_cpu_ptr > > > +} > > > + > > > +static void acomp_ctx_put_cpu(void) > > > +{ > > > + cpus_read_unlock(); > > > +} > > > + > > > static bool zswap_compress(struct folio *folio, struct zswap_entry *= entry) > > > { > > > struct crypto_acomp_ctx *acomp_ctx; > > > @@ -887,8 +902,7 @@ static bool zswap_compress(struct folio *folio, > > > struct zswap_entry *entry) > > > gfp_t gfp; > > > u8 *dst; > > > > > > - acomp_ctx =3D raw_cpu_ptr(entry->pool->acomp_ctx); > > > - > > > + acomp_ctx =3D acomp_ctx_get_cpu(entry->pool->acomp_ctx); > > > mutex_lock(&acomp_ctx->mutex); > > > > > > dst =3D acomp_ctx->buffer; > > > @@ -944,6 +958,7 @@ static bool zswap_compress(struct folio *folio, > > > struct zswap_entry *entry) > > > zswap_reject_alloc_fail++; > > > > > > mutex_unlock(&acomp_ctx->mutex); > > > + acomp_ctx_put_cpu(); > > > return comp_ret =3D=3D 0 && alloc_ret =3D=3D 0; > > > } > > > > > > @@ -954,7 +969,7 @@ static void zswap_decompress(struct zswap_entry > > > *entry, struct folio *folio) > > > struct crypto_acomp_ctx *acomp_ctx; > > > u8 *src; > > > > > > - acomp_ctx =3D raw_cpu_ptr(entry->pool->acomp_ctx); > > > + acomp_ctx =3D acompx_ctx_get_cpu(entry->pool->acomp_ctx); > > > mutex_lock(&acomp_ctx->mutex); > > > > > > src =3D zpool_map_handle(zpool, entry->handle, ZPOOL_MM_RO); > > > @@ -984,6 +999,7 @@ static void zswap_decompress(struct zswap_entry > > > *entry, struct folio *folio) > > > > > > if (src !=3D acomp_ctx->buffer) > > > zpool_unmap_handle(zpool, entry->handle); > > > + acomp_ctx_put_cpu(); > > > } > > > > > > /********************************* > > > > > > > > > > > > > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > > BUG: KASAN: slab-use-after-free in zswap_decompress+0x7d7/0x810 mm/= zswap.c:988 > > > > Read of size 4 at addr ffff888027874044 by task kswapd0/92 > > > > > > > > CPU: 1 UID: 0 PID: 92 Comm: kswapd0 Not tainted 6.12.0-09435-g2c22d= c1ee3a1 #11 > > > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > > > > rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014 > > > > Call Trace: > > > > > > > > __dump_stack lib/dump_stack.c:94 [inline] > > > > dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120 > > > > print_address_description mm/kasan/report.c:378 [inline] > > > > print_report+0xc0/0x5e0 mm/kasan/report.c:489 > > > > kasan_report+0xbd/0xf0 mm/kasan/report.c:602 > > > > zswap_decompress+0x7d7/0x810 mm/zswap.c:988 > > > > zswap_writeback_entry+0x1e9/0x860 mm/zswap.c:1058 > > > > shrink_memcg_cb+0x213/0x360 mm/zswap.c:1163 > > > > __list_lru_walk_one+0x15e/0x490 mm/list_lru.c:301 > > > > list_lru_walk_one+0x3e/0x50 mm/list_lru.c:338 > > > > list_lru_shrink_walk include/linux/list_lru.h:240 [inline] > > > > zswap_shrinker_scan+0x135/0x220 mm/zswap.c:1197 > > > > do_shrink_slab+0x44e/0x1190 mm/shrinker.c:437 > > > > shrink_slab_memcg mm/shrinker.c:550 [inline] > > > > shrink_slab+0xb61/0x12a0 mm/shrinker.c:628 > > > > shrink_one+0x4ad/0x7c0 mm/vmscan.c:4836 > > > > shrink_many mm/vmscan.c:4897 [inline] > > > > lru_gen_shrink_node mm/vmscan.c:4975 [inline] > > > > shrink_node+0x269a/0x3d60 mm/vmscan.c:5956 > > > > kswapd_shrink_node mm/vmscan.c:6785 [inline] > > > > balance_pgdat+0xbe5/0x18c0 mm/vmscan.c:6977 > > > > kswapd+0x6ff/0xd60 mm/vmscan.c:7246 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > > > > > Allocated by task 1: > > > > kasan_save_stack+0x24/0x50 mm/kasan/common.c:47 > > > > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > > > > poison_kmalloc_redzone mm/kasan/common.c:377 [inline] > > > > __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 > > > > kasan_kmalloc include/linux/kasan.h:260 [inline] > > > > __do_kmalloc_node mm/slub.c:4283 [inline] > > > > __kmalloc_noprof+0x212/0x530 mm/slub.c:4295 > > > > kmalloc_noprof include/linux/slab.h:905 [inline] > > > > kzalloc_noprof include/linux/slab.h:1037 [inline] > > > > __acomp_request_alloc_noprof include/crypto/internal/acompress.h:7= 5 [inline] > > > > acomp_request_alloc+0x46/0x110 crypto/acompress.c:131 > > > > zswap_cpu_comp_prepare+0x1f4/0x470 mm/zswap.c:840 > > > > cpuhp_invoke_callback+0x26d/0x9d0 kernel/cpu.c:204 > > > > cpuhp_issue_call+0x1c1/0x8d0 kernel/cpu.c:2375 > > > > __cpuhp_state_add_instance_cpuslocked+0x26a/0x3c0 kernel/cpu.c:243= 7 > > > > __cpuhp_state_add_instance+0xd7/0x2e0 kernel/cpu.c:2458 > > > > cpuhp_state_add_instance include/linux/cpuhotplug.h:386 [inline] > > > > zswap_pool_create+0x2c3/0x5c0 mm/zswap.c:288 > > > > __zswap_pool_create_fallback mm/zswap.c:356 [inline] > > > > zswap_setup+0x3a5/0x820 mm/zswap.c:1781 > > > > zswap_init+0x2d/0x40 mm/zswap.c:1817 > > > > do_one_initcall+0x111/0x6d0 init/main.c:1266 > > > > do_initcall_level init/main.c:1328 [inline] > > > > do_initcalls init/main.c:1344 [inline] > > > > do_basic_setup init/main.c:1363 [inline] > > > > kernel_init_freeable+0x5ae/0x8a0 init/main.c:1577 > > > > kernel_init+0x1e/0x2d0 init/main.c:1466 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > Freed by task 25: > > > > kasan_save_stack+0x24/0x50 mm/kasan/common.c:47 > > > > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > > > > kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:582 > > > > poison_slab_object mm/kasan/common.c:247 [inline] > > > > __kasan_slab_free+0x54/0x70 mm/kasan/common.c:264 > > > > kasan_slab_free include/linux/kasan.h:233 [inline] > > > > slab_free_hook mm/slub.c:2338 [inline] > > > > slab_free mm/slub.c:4598 [inline] > > > > kfree+0x14e/0x4d0 mm/slub.c:4746 > > > > zswap_cpu_comp_dead+0xe3/0x1c0 mm/zswap.c:874 > > > > cpuhp_invoke_callback+0x564/0x9d0 kernel/cpu.c:216 > > > > __cpuhp_invoke_callback_range+0x104/0x220 kernel/cpu.c:965 > > > > cpuhp_invoke_callback_range kernel/cpu.c:989 [inline] > > > > cpuhp_down_callbacks kernel/cpu.c:1382 [inline] > > > > _cpu_down+0x41d/0xef0 kernel/cpu.c:1443 > > > > __cpu_down_maps_locked+0x6f/0x90 kernel/cpu.c:1473 > > > > work_for_cpu_fn+0x55/0xa0 kernel/workqueue.c:6719 > > > > process_one_work+0x9a2/0x1ba0 kernel/workqueue.c:3229 > > > > process_scheduled_works kernel/workqueue.c:3310 [inline] > > > > worker_thread+0x677/0xe90 kernel/workqueue.c:3391 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > The buggy address belongs to the object at ffff888027874000 > > > > which belongs to the cache kmalloc-96 of size 96 > > > > The buggy address is located 68 bytes inside of > > > > freed 96-byte region [ffff888027874000, ffff888027874060) > > > > > > > > The buggy address belongs to the physical page: > > > > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:= 0x27874 > > > > flags: 0xfff00000000000(node=3D0|zone=3D1|lastcpupid=3D0x7ff) > > > > page_type: f5(slab) > > > > raw: 00fff00000000000 ffff88801b041280 dead000000000100 dead0000000= 00122 > > > > raw: 0000000000000000 0000000000200020 00000001f5000000 00000000000= 00000 > > > > page dumped because: kasan: bad access detected > > > > page_owner tracks the page as allocated > > > > page last allocated via order 0, migratetype Unmovable, gfp_mask > > > > 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, t= gid > > > > 1 (swapper/0), ts 20389586985, free_ts 18720773637 > > > > set_page_owner include/linux/page_owner.h:32 [inline] > > > > post_alloc_hook+0x2e7/0x350 mm/page_alloc.c:1556 > > > > prep_new_page mm/page_alloc.c:1564 [inline] > > > > get_page_from_freelist+0xe4e/0x2b20 mm/page_alloc.c:3474 > > > > __alloc_pages_noprof+0x219/0x21f0 mm/page_alloc.c:4751 > > > > alloc_pages_mpol_noprof+0x2b6/0x600 mm/mempolicy.c:2265 > > > > alloc_slab_page mm/slub.c:2408 [inline] > > > > allocate_slab mm/slub.c:2574 [inline] > > > > new_slab+0x2d5/0x420 mm/slub.c:2627 > > > > ___slab_alloc+0xbb7/0x1850 mm/slub.c:3815 > > > > __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3905 > > > > __slab_alloc_node mm/slub.c:3980 [inline] > > > > slab_alloc_node mm/slub.c:4141 [inline] > > > > __do_kmalloc_node mm/slub.c:4282 [inline] > > > > __kmalloc_noprof+0x2ac/0x530 mm/slub.c:4295 > > > > kmalloc_noprof include/linux/slab.h:905 [inline] > > > > kzalloc_noprof include/linux/slab.h:1037 [inline] > > > > __acomp_request_alloc_noprof include/crypto/internal/acompress.h:7= 5 [inline] > > > > acomp_request_alloc+0x46/0x110 crypto/acompress.c:131 > > > > zswap_cpu_comp_prepare+0x1f4/0x470 mm/zswap.c:840 > > > > cpuhp_invoke_callback+0x26d/0x9d0 kernel/cpu.c:204 > > > > cpuhp_issue_call+0x1c1/0x8d0 kernel/cpu.c:2375 > > > > __cpuhp_state_add_instance_cpuslocked+0x26a/0x3c0 kernel/cpu.c:243= 7 > > > > __cpuhp_state_add_instance+0xd7/0x2e0 kernel/cpu.c:2458 > > > > cpuhp_state_add_instance include/linux/cpuhotplug.h:386 [inline] > > > > zswap_pool_create+0x2c3/0x5c0 mm/zswap.c:288 > > > > __zswap_pool_create_fallback mm/zswap.c:356 [inline] > > > > zswap_setup+0x3a5/0x820 mm/zswap.c:1781 > > > > page last free pid 54 tgid 54 stack trace: > > > > reset_page_owner include/linux/page_owner.h:25 [inline] > > > > free_pages_prepare mm/page_alloc.c:1127 [inline] > > > > free_unref_page+0x714/0x10c0 mm/page_alloc.c:2657 > > > > vfree+0x17e/0x890 mm/vmalloc.c:3382 > > > > delayed_vfree_work+0x57/0x70 mm/vmalloc.c:3303 > > > > process_one_work+0x9a2/0x1ba0 kernel/workqueue.c:3229 > > > > process_scheduled_works kernel/workqueue.c:3310 [inline] > > > > worker_thread+0x677/0xe90 kernel/workqueue.c:3391 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > Memory state around the buggy address: > > > > ffff888027873f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > > > ffff888027873f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > > > >ffff888027874000: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > > > > ^ > > > > ffff888027874080: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc > > > > ffff888027874100: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > > We also find a similar bug report in function zswap_store(), listed= as below: > > > > > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > > BUG: KASAN: slab-use-after-free in zswap_compress mm/zswap.c:925 [i= nline] > > > > BUG: KASAN: slab-use-after-free in zswap_store_page mm/zswap.c:1426= [inline] > > > > BUG: KASAN: slab-use-after-free in zswap_store+0x2307/0x25e0 mm/zsw= ap.c:1533 > > > > Read of size 4 at addr ffff8880219f6b44 by task kswapd0/88 > > > > > > > > CPU: 1 UID: 0 PID: 88 Comm: kswapd0 Tainted: G U > > > > 6.12.0-09435-g2c22dc1ee3a1 #11 > > > > Tainted: [U]=3DUSER > > > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > > > > rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014 > > > > Call Trace: > > > > > > > > __dump_stack lib/dump_stack.c:94 [inline] > > > > dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120 > > > > print_address_description mm/kasan/report.c:378 [inline] > > > > print_report+0xc0/0x5e0 mm/kasan/report.c:489 > > > > kasan_report+0xbd/0xf0 mm/kasan/report.c:602 > > > > zswap_compress mm/zswap.c:925 [inline] > > > > zswap_store_page mm/zswap.c:1426 [inline] > > > > zswap_store+0x2307/0x25e0 mm/zswap.c:1533 > > > > swap_writepage+0x3a8/0xe50 mm/page_io.c:279 > > > > pageout+0x3b9/0xa90 mm/vmscan.c:689 > > > > shrink_folio_list+0x2988/0x4340 mm/vmscan.c:1367 > > > > evict_folios+0x72b/0x1a10 mm/vmscan.c:4593 > > > > try_to_shrink_lruvec+0x62b/0xa60 mm/vmscan.c:4789 > > > > shrink_one+0x417/0x7c0 mm/vmscan.c:4834 > > > > shrink_many mm/vmscan.c:4897 [inline] > > > > lru_gen_shrink_node mm/vmscan.c:4975 [inline] > > > > shrink_node+0x269a/0x3d60 mm/vmscan.c:5956 > > > > kswapd_shrink_node mm/vmscan.c:6785 [inline] > > > > balance_pgdat+0xbe5/0x18c0 mm/vmscan.c:6977 > > > > kswapd+0x6ff/0xd60 mm/vmscan.c:7246 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > > > > > Allocated by task 1: > > > > kasan_save_stack+0x24/0x50 mm/kasan/common.c:47 > > > > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > > > > poison_kmalloc_redzone mm/kasan/common.c:377 [inline] > > > > __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 > > > > kasan_kmalloc include/linux/kasan.h:260 [inline] > > > > __do_kmalloc_node mm/slub.c:4283 [inline] > > > > __kmalloc_noprof+0x212/0x530 mm/slub.c:4295 > > > > kmalloc_noprof include/linux/slab.h:905 [inline] > > > > kzalloc_noprof include/linux/slab.h:1037 [inline] > > > > __acomp_request_alloc_noprof include/crypto/internal/acompress.h:7= 5 [inline] > > > > acomp_request_alloc+0x46/0x110 crypto/acompress.c:131 > > > > zswap_cpu_comp_prepare+0x1f4/0x470 mm/zswap.c:840 > > > > cpuhp_invoke_callback+0x26d/0x9d0 kernel/cpu.c:204 > > > > cpuhp_issue_call+0x1c1/0x8d0 kernel/cpu.c:2375 > > > > __cpuhp_state_add_instance_cpuslocked+0x26a/0x3c0 kernel/cpu.c:243= 7 > > > > __cpuhp_state_add_instance+0xd7/0x2e0 kernel/cpu.c:2458 > > > > cpuhp_state_add_instance include/linux/cpuhotplug.h:386 [inline] > > > > zswap_pool_create+0x2c3/0x5c0 mm/zswap.c:288 > > > > __zswap_pool_create_fallback mm/zswap.c:356 [inline] > > > > zswap_setup+0x3a5/0x820 mm/zswap.c:1781 > > > > zswap_init+0x2d/0x40 mm/zswap.c:1817 > > > > do_one_initcall+0x111/0x6d0 init/main.c:1266 > > > > do_initcall_level init/main.c:1328 [inline] > > > > do_initcalls init/main.c:1344 [inline] > > > > do_basic_setup init/main.c:1363 [inline] > > > > kernel_init_freeable+0x5ae/0x8a0 init/main.c:1577 > > > > kernel_init+0x1e/0x2d0 init/main.c:1466 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > Freed by task 901: > > > > kasan_save_stack+0x24/0x50 mm/kasan/common.c:47 > > > > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > > > > kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:582 > > > > poison_slab_object mm/kasan/common.c:247 [inline] > > > > __kasan_slab_free+0x54/0x70 mm/kasan/common.c:264 > > > > kasan_slab_free include/linux/kasan.h:233 [inline] > > > > slab_free_hook mm/slub.c:2338 [inline] > > > > slab_free mm/slub.c:4598 [inline] > > > > kfree+0x14e/0x4d0 mm/slub.c:4746 > > > > zswap_cpu_comp_dead+0xe3/0x1c0 mm/zswap.c:874 > > > > cpuhp_invoke_callback+0x564/0x9d0 kernel/cpu.c:216 > > > > __cpuhp_invoke_callback_range+0x104/0x220 kernel/cpu.c:965 > > > > cpuhp_invoke_callback_range kernel/cpu.c:989 [inline] > > > > cpuhp_down_callbacks kernel/cpu.c:1382 [inline] > > > > _cpu_down+0x41d/0xef0 kernel/cpu.c:1443 > > > > __cpu_down_maps_locked+0x6f/0x90 kernel/cpu.c:1473 > > > > work_for_cpu_fn+0x55/0xa0 kernel/workqueue.c:6719 > > > > process_one_work+0x9a2/0x1ba0 kernel/workqueue.c:3229 > > > > process_scheduled_works kernel/workqueue.c:3310 [inline] > > > > worker_thread+0x677/0xe90 kernel/workqueue.c:3391 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > The buggy address belongs to the object at ffff8880219f6b00 > > > > which belongs to the cache kmalloc-96 of size 96 > > > > The buggy address is located 68 bytes inside of > > > > freed 96-byte region [ffff8880219f6b00, ffff8880219f6b60) > > > > > > > > The buggy address belongs to the physical page: > > > > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:= 0x219f6 > > > > anon flags: 0xfff00000000000(node=3D0|zone=3D1|lastcpupid=3D0x7ff) > > > > page_type: f5(slab) > > > > raw: 00fff00000000000 ffff88801b041280 ffffea0000887d00 dead0000000= 00005 > > > > raw: 0000000000000000 0000000000200020 00000001f5000000 00000000000= 00000 > > > > page dumped because: kasan: bad access detected > > > > page_owner tracks the page as allocated > > > > page last allocated via order 0, migratetype Unmovable, gfp_mask > > > > 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, t= gid > > > > 1 (swapper/0), ts 15792736110, free_ts 14433067061 > > > > set_page_owner include/linux/page_owner.h:32 [inline] > > > > post_alloc_hook+0x2e7/0x350 mm/page_alloc.c:1556 > > > > prep_new_page mm/page_alloc.c:1564 [inline] > > > > get_page_from_freelist+0xe4e/0x2b20 mm/page_alloc.c:3474 > > > > __alloc_pages_noprof+0x219/0x21f0 mm/page_alloc.c:4751 > > > > alloc_pages_mpol_noprof+0x2b6/0x600 mm/mempolicy.c:2265 > > > > alloc_slab_page mm/slub.c:2408 [inline] > > > > allocate_slab mm/slub.c:2574 [inline] > > > > new_slab+0x2d5/0x420 mm/slub.c:2627 > > > > ___slab_alloc+0xbb7/0x1850 mm/slub.c:3815 > > > > __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3905 > > > > __slab_alloc_node mm/slub.c:3980 [inline] > > > > slab_alloc_node mm/slub.c:4141 [inline] > > > > __kmalloc_cache_noprof+0x280/0x410 mm/slub.c:4309 > > > > kmalloc_noprof include/linux/slab.h:901 [inline] > > > > kzalloc_noprof include/linux/slab.h:1037 [inline] > > > > usb_hub_create_port_device+0xbb/0xde0 drivers/usb/core/port.c:743 > > > > hub_configure drivers/usb/core/hub.c:1710 [inline] > > > > hub_probe+0x1ceb/0x2fc0 drivers/usb/core/hub.c:1965 > > > > usb_probe_interface+0x314/0x9f0 drivers/usb/core/driver.c:399 > > > > call_driver_probe drivers/base/dd.c:579 [inline] > > > > really_probe+0x252/0xa90 drivers/base/dd.c:658 > > > > __driver_probe_device+0x1df/0x450 drivers/base/dd.c:800 > > > > driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830 > > > > __device_attach_driver+0x1db/0x2f0 drivers/base/dd.c:958 > > > > bus_for_each_drv+0x14c/0x1d0 drivers/base/bus.c:459 > > > > page last free pid 25 tgid 25 stack trace: > > > > reset_page_owner include/linux/page_owner.h:25 [inline] > > > > free_pages_prepare mm/page_alloc.c:1127 [inline] > > > > free_unref_page+0x714/0x10c0 mm/page_alloc.c:2657 > > > > vfree+0x17e/0x890 mm/vmalloc.c:3382 > > > > delayed_vfree_work+0x57/0x70 mm/vmalloc.c:3303 > > > > process_one_work+0x9a2/0x1ba0 kernel/workqueue.c:3229 > > > > process_scheduled_works kernel/workqueue.c:3310 [inline] > > > > worker_thread+0x677/0xe90 kernel/workqueue.c:3391 > > > > kthread+0x2ca/0x3b0 kernel/kthread.c:389 > > > > ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > Memory state around the buggy address: > > > > ffff8880219f6a00: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc > > > > ffff8880219f6a80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc > > > > >ffff8880219f6b00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > > > > ^ > > > > ffff8880219f6b80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc > > > > ffff8880219f6c00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > > If you have any questions, please contact us. > > > > > > > > Best Regards, > > > > Yue