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        "ID": "CVE-2024-47679",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfs: fix race between evice_inodes() and find_inode()&iput()\n\nHi, all\n\nRecently I noticed a bug[1] in btrfs, after digged it into\nand I believe it'a race in vfs.\n\nLet's assume there's a inode (ie ino 261) with i_count 1 is\ncalled by iput(), and there's a concurrent thread calling\ngeneric_shutdown_super().\n\ncpu0:                              cpu1:\niput() // i_count is 1\n  ->spin_lock(inode)\n  ->dec i_count to 0\n  ->iput_final()                    generic_shutdown_super()\n    ->__inode_add_lru()               ->evict_inodes()\n      // cause some reason[2]           ->if (atomic_read(inode->i_count)) continue;\n      // return before                  // inode 261 passed the above check\n      // list_lru_add_obj()             // and then schedule out\n   ->spin_unlock()\n// note here: the inode 261\n// was still at sb list and hash list,\n// and I_FREEING|I_WILL_FREE was not been set\n\nbtrfs_iget()\n  // after some function calls\n  ->find_inode()\n    // found the above inode 261\n    ->spin_lock(inode)\n   // check I_FREEING|I_WILL_FREE\n   // and passed\n      ->__iget()\n    ->spin_unlock(inode)                // schedule back\n                                        ->spin_lock(inode)\n                                        // check (I_NEW|I_FREEING|I_WILL_FREE) flags,\n                                        // passed and set I_FREEING\niput()                                  ->spin_unlock(inode)\n  ->spin_lock(inode)\t\t\t  ->evict()\n  // dec i_count to 0\n  ->iput_final()\n    ->spin_unlock()\n    ->evict()\n\nNow, we have two threads simultaneously evicting\nthe same inode, which may trigger the BUG(inode->i_state & I_CLEAR)\nstatement both within clear_inode() and iput().\n\nTo fix the bug, recheck the inode->i_count after holding i_lock.\nBecause in the most scenarios, the first check is valid, and\nthe overhead of spin_lock() can be reduced.\n\nIf there is any misunderstanding, please let me know, thanks.\n\n[1]: https://lore.kernel.org/linux-btrfs/000000000000eabe1d0619c48986@google.com/\n[2]: The reason might be 1. SB_ACTIVE was removed or 2. mapping_shrinkable()\nreturn false when I reproduced the bug."
            }
        ]
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            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
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    },
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        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
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                                            "version_affected": "<",
                                            "version_name": "63997e98a3be",
                                            "version_value": "47a68c75052a"
                                        },
                                        {
                                            "version_value": "not down converted",
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                                                    {
                                                        "version": "2.6.37",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "2.6.37",
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                                                        "versionType": "custom"
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                                                        "version": "5.10.227",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
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                                                        "version": "5.15.168",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
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                                                        "version": "6.1.113",
                                                        "lessThanOrEqual": "6.1.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
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                                                    {
                                                        "version": "6.6.54",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
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                                                    {
                                                        "version": "6.10.13",
                                                        "lessThanOrEqual": "6.10.*",
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                "name": "https://git.kernel.org/stable/c/3721a69403291e2514d13a7c3af50a006ea1153b"
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                "name": "https://git.kernel.org/stable/c/0f8a5b6d0dafa4f533ac82e98f8b812073a7c9d1"
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                "name": "https://git.kernel.org/stable/c/6c857fb12b9137fee574443385d53914356bbe11"
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                "name": "https://git.kernel.org/stable/c/88b1afbf0f6b221f6c5bb66cc80cd3b38d696687"
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