From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f172.google.com (mail-yw1-f172.google.com [209.85.128.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79A0A40D586 for ; Sun, 14 Jun 2026 22:02:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781474564; cv=none; b=jyCkPXscCkUwJn/+TnkHWf9hm2fa6clOlgvWu9kT8wncf5TNKQ1emGdDuWR3U5JnLRuYp67J0kImlBcU0nMJ7B44D6bvqnyW+4Fr/vJHBDv9CnlYpHyVYrzZ8XyupPbI+epeUOwiRI4pQbwssN1XHPgpSUV1Edb+gF/qreZI9fo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781474564; c=relaxed/simple; bh=nLIX5X43/8FIrNBR9qYbjAZYRY1X8Bo8AYb4vUeLGpA=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=AlVwSpB+0IGlaqYHwxuAfis9/e3wRIQ2hWYKc97Nm5HVCQO3l9bhmGpR2cxW38nJGW9XdRAe7T9GNVuebrrUQKLnCFoD1CAhDdTN25uKWmgTDsK6BSwGgNAPfsOk7Rq6j8qWYzYP5POwCtv+DgdqQHGty73TvRj++PoQBJq1bLs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=s+8jRsYU; arc=none smtp.client-ip=209.85.128.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="s+8jRsYU" Received: by mail-yw1-f172.google.com with SMTP id 00721157ae682-7e8833c99fcso27749957b3.3 for ; Sun, 14 Jun 2026 15:02:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1781474562; x=1782079362; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:from:to:cc:subject:date:message-id:reply-to; bh=hcAFFbPAP2Q2h6idwJ3ZC7xWIHvpapDwn0WSEWg/X2Y=; b=s+8jRsYUKFnJ7odxPkOTPyEk0AbuUecWuQmbhfY7BqMb6rJo/eEJ9u34d+ySjChdq4 iWchC24+rpmJFFFz1cgdAAeoccAS20kV0enerkY/KKSda+QJ/2psF1MS3FbQzOBy7DgL Ok3FlyzQl5YJKQDYas865D+Cc3HMUt8N7eFgNpooSH2IjnJZmR0zLeF7Wk3j1Qv5OkJY R3r4ywbfejU/ULCX2+xxRRdTwXs6Ot36NFuN/peKiyV5evwCFRjFjn+BwpArWGUJGKc4 SbcLctBeO5vogxz8842TG9eBx1mzpiVFtwvEm7HRbah2ZzRAmUvxGgba3iNekQlsHgQs HGeQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781474562; x=1782079362; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hcAFFbPAP2Q2h6idwJ3ZC7xWIHvpapDwn0WSEWg/X2Y=; b=JAU/F7RXjabHtxFkR0JkvdHR96PsTkx8yEf4U0G55sZDTK11blsA8IjSf3rADDNQdB vYCL1jyc8pT2TZMNMhk95Akt5NToJ+mep0Peu3HKyGv3CUwOAQm7eQHawDCOEKsyfe+g rSzG3Gk1JJb2e1Alx8BRZPJD2yzT7IYcVjICFhkVfmCZrQvvLbiXpR+WxqcwqMkqjY/C X+KXUdTKVEsxPKFZ3hU+xdCQywPm9nFcC5nnMPvBAYzQ6zSM7t7DioU0K9bB4up54v/J 7N8ctS1H/yN46xpkg8g77N5e7cLzgs2huKUgk918mIhkTrUYrz9jcNokOfsf/5cpiPY4 85jA== X-Forwarded-Encrypted: i=1; AFNElJ81dVRyNSCRjhqjOG7C6wjcwv+SN1RNs05BdV0s1LV3KvtlEasAskzNwqgQzvAuVhLPz0W1bBv/YvYKfqI=@vger.kernel.org X-Gm-Message-State: AOJu0YzL3eHwDAz8LRXhM+P50wwnjWm00U/AetwtV/trB6nYzzUjkiRR EibRBN1RRTHBQ96LRsimW6C533QcOacabtuMpe9UEoey3NdhK9dI4QiO X-Gm-Gg: Acq92OE5hJ3zgQ0ZGOGgMMXP7CCtXRZku+/LQwwS8UqPHPb0FrhIuk9M2xqDWim/2S3 9NzXj5ntziXIDeYat4OaY3t0okg+D6+2n5WBVW0+CqwKnp7i7aVLna92qpsbGUsxK+K4FZZZVG7 4s2mXiT1pTVxb9GlqOErh4i5/yJDTwUHbkbn4TnxW8EJJ5doVkkk1JVo9wkPcn33vhXDSLLWKIW wVq44uoyCCMZw09h+VWIHg371IW4jLNAfnQsnliquxIGgfVvN61NNITOWcYPAN7zeGpxL6LvvDF Cf6/45t7CLfvo7nxrC1QaAfhDD4HclKoQlpBHzx6vf/VgE2LKc35W62EirBdvKuLB3jhx3CbUvA Xo7AtLI69mSlY0mD/ffE/zaXdq7uurHlRdwDtpOQhASOmLFeiKTA6qSKH1EePDsZMV6Vj+gDLVV 1Sj0RYxw3pVLDOUeeJnrKYyXdFJ5MdQ2U8pC6Ikk+H6jaGSuWsQqDhGL4xgkKCeMPDzkn+3lrqg A== X-Received: by 2002:a05:690c:998e:b0:7c0:56f:5b70 with SMTP id 00721157ae682-7f7bcf107c3mr112549197b3.29.1781474562359; Sun, 14 Jun 2026 15:02:42 -0700 (PDT) Received: from localhost.localdomain ([2607:fb91:14e1:4204:4d87:aacf:f5f1:c2dd]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8d304577accsm90901256d6.25.2026.06.14.15.02.40 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Sun, 14 Jun 2026 15:02:42 -0700 (PDT) From: Shuangpeng Bai To: kashyap.desai@broadcom.com, sumit.saxena@broadcom.com, shivasharan.srikanteshwara@broadcom.com, chandrakanth.patil@broadcom.com, James.Bottomley@HansenPartnership.com, martin.petersen@oracle.com, megaraidlinux.pdl@broadcom.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [BUG] KASAN: slab-use-after-free in is_free_buddy_page from megaraid_sas Date: Sun, 14 Jun 2026 18:02:30 -0400 Message-ID: <178144969601.60470.16745418177798279969@gmail.com> X-Mailer: git-send-email 2.47.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi Kernel Maintainers, I hit the following report while testing current upstream kernel: KASAN: slab-use-after-free in is_free_buddy_page from megaraid_sas I reproduced this on commit: e8c2f9fdadee7cbc75134dc463c1e0d856d6e5c7 (May 25 2026) The reproducer and .config files are here. https://gist.github.com/shuangpengbai/e04467b211a84fbdea66596b50fac4bc I'm happy to test debug patches or provide additional information. Reported-by: Shuangpeng Bai [ 114.160510][ T8384] BUG: KASAN: slab-use-after-free in is_free_buddy_page (include/linux/page-flags.h:993 mm/page_alloc.c:7426) [ 114.161332][ T8384] Read of size 4 at addr ffff8881263a0030 by task repro_megasas/8384 [ 114.162155][ T8384] [ 114.162413][ T8384] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 114.162417][ T8384] Call Trace: [ 114.162420][ T8384] [ 114.162422][ T8384] dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120) [ 114.162429][ T8384] print_report (mm/kasan/report.c:378 mm/kasan/report.c:482) [ 114.162446][ T8384] kasan_report (mm/kasan/report.c:595) [ 114.162455][ T8384] is_free_buddy_page (include/linux/page-flags.h:993 mm/page_alloc.c:7426) [ 114.162459][ T8384] set_ps_flags (mm/util.c:1294) [ 114.162464][ T8384] snapshot_page (mm/util.c:1333) [ 114.162469][ T8384] dump_page (mm/debug.c:134 mm/debug.c:146) [ 114.162517][ T8384] __get_pfnblock_flags_mask (mm/page_alloc.c:357 mm/page_alloc.c:384) [ 114.162521][ T8384] get_pfnblock_migratetype (mm/page_alloc.c:432) [ 114.162529][ T8384] dump_page (mm/debug.c:115 mm/debug.c:138 mm/debug.c:146) [ 114.162548][ T8384] ___free_pages (include/linux/mm.h:1766 mm/page_alloc.c:5306) [ 114.162552][ T8384] megasas_mgmt_fw_ioctl (drivers/scsi/megaraid/megaraid_sas_base.c:?) [ 114.162579][ T8384] megasas_mgmt_ioctl_fw (drivers/scsi/megaraid/megaraid_sas_base.c:8570) [ 114.162583][ T8384] megasas_mgmt_ioctl (drivers/scsi/megaraid/megaraid_sas_base.c:8628) [ 114.162586][ T8384] __se_sys_ioctl (fs/ioctl.c:51 fs/ioctl.c:597 fs/ioctl.c:583) [ 114.162591][ T8384] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 114.162596][ T8384] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) [ 114.162600][ T8384] RIP: 0033:0x7fd4bdfc4237 [ 114.162604][ T8384] Code: 00 00 00 48 8b 05 59 cc 0d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 29 cc 0d 00 f7 d8 64 89 01 48 [ 114.162607][ T8384] RSP: 002b:00007fd4ba6c6d28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 114.162612][ T8384] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd4bdfc4237 [ 114.162615][ T8384] RDX: 00007fd4ba6c6d30 RSI: 00000000c1944d01 RDI: 000000000000000a [ 114.162618][ T8384] RBP: 00007fd4ba6c6d30 R08: 0000000000000000 R09: 00007fd4ba6c8700 [ 114.162619][ T8384] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a [ 114.162621][ T8384] R13: 0101000000001000 R14: 0000000100000028 R15: 0000000000802000 [ 114.162626][ T8384] [ 114.162627][ T8384] [ 114.166559][ T8384] Freed by task 8342 on cpu 0 at 70.147016s: [ 114.167592][ T8384] kasan_save_track (mm/kasan/common.c:57 mm/kasan/common.c:78) [ 114.167598][ T8384] kasan_save_free_info (mm/kasan/generic.c:584) [ 114.167602][ T8384] __kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285) [ 114.167606][ T8384] kfree (include/linux/kasan.h:235 mm/slub.c:2689 mm/slub.c:6251 mm/slub.c:6566) [ 114.167611][ T8384] tomoyo_realpath_from_path (security/tomoyo/realpath.c:286) [ 114.167618][ T8384] tomoyo_check_open_permission (security/tomoyo/file.c:151 security/tomoyo/file.c:776) [ 114.171898][ T8384] security_file_open (security/security.c:2739) [ 114.172838][ T8384] do_dentry_open (fs/open.c:924) [ 114.173900][ T8384] vfs_open (fs/open.c:1079) [ 114.173905][ T8384] path_openat (fs/namei.c:4699 fs/namei.c:4858) [ 114.173908][ T8384] do_file_open (fs/namei.c:4887) [ 114.174796][ T8384] do_sys_openat2 (fs/open.c:1364) [ 114.174801][ T8384] __x64_sys_openat (fs/open.c:1370 fs/open.c:1386 fs/open.c:1381 fs/open.c:1381) [ 114.179693][ T8384] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 114.180735][ T8384] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) [ 114.180739][ T8384] [ 114.180740][ T8384] The buggy address belongs to the object at ffff8881263a0000 [ 114.180740][ T8384] which belongs to the cache kmalloc-4k of size 4096 [ 114.180743][ T8384] The buggy address is located 48 bytes inside of [ 114.180743][ T8384] freed 4096-byte region [ffff8881263a0000, ffff8881263a1000) [ 114.188131][ T8384] Best, Shuangpeng