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([218.28.192.28]) by newxmesmtplogicsvrszc43-0.qq.com (NewEsmtp) with SMTP id 4192A03A; Fri, 06 Nov 2026 17:16:25 +0800 X-QQ-mid: xmsmtpt1793956585tk93hi8a4 Message-ID: X-QQ-XMAILINFO: MDbayGdXPuoex5frKWRRy3d9y5cbZtT8RsCG+Yb3O57bGmK8/Zjcl9RKzPYwnK 4uu0PfebxcBvHvL0deZnBgk/H05tzr8HW7XhVho5tcsEwIrrmAcsRLmz07MOWShBIIZYrZ8l5PP8 B+Lq7tm28dAVlAhG+IZaGWd/x1Zsh1pgwLjBiD2isTCuNG7riQzHVpZ/JjhOlvQFekc345UgMTx3 iClTh+XtN0ESjG6siWI/xLl/kEX/abBfksT9n2UB+wJNUEwYJBx8gkklTbnjeAUaXq5XOxdkwnHp d7HmPRT8PNXTgZcmlylhTEsgLZ+sCZJvLQV4olLE1K8Jkw380MFMEyuIlBwOOa6eod94fEwF7aSs Lb3Sqhjnq6kmy3dvsyT3loM1ngLODDoeGPf+snK7524mWUWDzBMBxEX5nNlt2wPB3aP5DCeC5oh0 UFJiljebEtIBZkG3MgjzQoXTb1OjceQ6MZerW5l1TUAkO5xLfsNyjv0/2y0AZFl6I9DSIjXmLoFu DxH0qfECrb3mRnBG8Cc5unQVBGAcAIs9NqWHsRzh4Z7UGRovEXl8faGwbGeTQa0PAR9aWjxtlntb fejxrMWs0H3nLhYTwNgdU8ukj0La5akfUdwPhZ02o5csn3EgDGOLZn4WEcA8VoCmt895gdIjX0ta JGmO46o7XYLX4xWCg/ssZXEbcytUH04I/OEPYaMgh6TK0jRhewDOE3gNGL6exoTsJsVFZLSRPAnE CyuPF3H7q/TUcsjOYtMCpPNYQV48RNuyN3/LsVH1EfL5kozjNuC33VwDUIEDsqZKacNCSFEW/ZyK UPIbHSoIn4Wbot+9RNkU9xFGKrzft7gemH1HXrLU7sjdSv5p6PpZLVMvAUvmDp2wWnUj2hvpzXn6 z+S8I6CuW/nO4CgSId5q0ZPCrj8Qv44Z2ELKQXyeYplq9U/Cz4BQ9G3GIROZwRFzEbQqI3hidw4/ 3YRr3CjByNTwIjji63umsAG7QlMDLpbRkz+oX0+qNFw9VMuQiZAqSKVkdEXD974F8/FqvBAWL93w 7kWp4+xQMpOzJwHJNfszan3vgk8Q2AeRGNENa6ZbGFQzkjAf8qOpz7eCl1y3llZOs8uOgZDRce/f umMwnpu74qST/ryugeoSyFq52LSw== X-QQ-XMRINFO: NI4Ajvh11aEjEMj13RCX7UuhPEoou2bs1g== From: Shuai Liu <847807867@qq.com> To: jack@suse.cz Cc: linux-ext4@vger.kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, libaokun@linux.alibaba.com, ojaswin@linux.ibm.com, ritesh.list@gmail.com, yi.zhang@huawei.com, sashiko-bot@kernel.org, syzbot+09bec78ee77613a3efdd@syzkaller.appspotmail.com, linux-kernel@vger.kernel.org, Shuai Liu <847807867@qq.com> Subject: Re: [PATCH v8] ext4: fix slab-use-after-free in do_split() Date: Fri, 6 Nov 2026 17:16:25 +0800 X-OQ-MSGID: <20261106091625.707374-1-847807867@qq.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Honza, Thank you for the detailed review and the honest feedback. You are right - I was iterating against the AI review bot's findings without pausing to seek human feedback, and that was the wrong prioritization. I also agree with your point on maintainability: disk metadata can be corrupted in unbounded ways, ext4 has always treated graceful handling as best effort, and adding per-alias checks at every call site is expensive protection for a niche case. Given that, how would you like to proceed? The syzbot crash itself is real (KASAN slab-use-after-free from aliased buffer heads), so I could downscale this to a minimal fix for the actual reported crash (just the do_split() *bh/bh2 alias check) if you think that single check is worthwhile. Alternatively I can drop the series entirely, and I would be interested in helping explore the buffer_head metadata tag approach you outlined, if that is something you would welcome. Thanks again, Shuai Liu