{"uuid": "e7027454-a5b5-4a48-88e3-373934c2805e", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2024-56780", "type": "published-proof-of-concept", "source": "https://t.me/DarkWebInformer_CVEAlerts/773", "content": "\ud83d\udd17 DarkWebInformer.com - Cyber Threat Intelligence\n\ud83d\udccc CVE ID: CVE-2024-56780\n\ud83d\udd39 Description: In the Linux kernel, the following vulnerability has been resolved:\n\nquota: flush quota_release_work upon quota writeback\n\nOne of the paths quota writeback is called from is:\n\nfreeze_super()\n  sync_filesystem()\n    ext4_sync_fs()\n      dquot_writeback_dquots()\n\nSince we currently don't always flush the quota_release_work queue in\nthis path, we can end up with the following race:\n\n 1. dquot are added to releasing_dquots list during regular operations.\n 2. FS Freeze starts, however, this does not flush the quota_release_work queue.\n 3. Freeze completes.\n 4. Kernel eventually tries to flush the workqueue while FS is frozen which\n    hits a WARN_ON since transaction gets started during frozen state:\n\n  ext4_journal_check_start+0x28/0x110 [ext4] (unreliable)\n  __ext4_journal_start_sb+0x64/0x1c0 [ext4]\n  ext4_release_dquot+0x90/0x1d0 [ext4]\n  quota_release_workfn+0x43c/0x4d0\n\nWhich is the following line:\n\n  WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);\n\nWhich ultimately results in generic/390 failing due to dmesg\nnoise. This was detected on powerpc machine 15 cores.\n\nTo avoid this, make sure to flush the workqueue during\ndquot_writeback_dquots() so we dont have any pending workitems after\nfreeze.\n\ud83d\udccf Published: 2025-01-08T17:49:17.889Z\n\ud83d\udccf Modified: 2025-01-08T17:49:17.889Z\n\ud83d\udd17 References:\n1. https://git.kernel.org/stable/c/a5abba5e0e586e258ded3e798fe5f69c66fec198\n2. https://git.kernel.org/stable/c/6f3821acd7c3143145999248087de5fb4b48cf26\n3. https://git.kernel.org/stable/c/ab6cfcf8ed2c7496f55d020b65b1d8cd55d9a2cb\n4. https://git.kernel.org/stable/c/3e6ff207cd5bd924ad94cd1a7c633bcdac0ba1cb\n5. https://git.kernel.org/stable/c/bcacb52a985f1b6d280f698a470b873dfe52728a\n6. https://git.kernel.org/stable/c/8ea87e34792258825d290f4dc5216276e91cb224\n7. https://git.kernel.org/stable/c/ac6f420291b3fee1113f21d612fa88b628afab5b", "creation_timestamp": "2025-01-08T18:21:03.000000Z"}