{
  "affected": [],
  "aliases": [
    "CVE-2024-50228"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-362"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-11-09T11:15:08Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: shmem: fix data-race in shmem_getattr()\n\nI got the following KCSAN report during syzbot testing:\n\n==================================================================\nBUG: KCSAN: data-race in generic_fillattr / inode_set_ctime_current\n\nwrite to 0xffff888102eb3260 of 4 bytes by task 6565 on cpu 1:\n inode_set_ctime_to_ts include/linux/fs.h:1638 [inline]\n inode_set_ctime_current+0x169/0x1d0 fs/inode.c:2626\n shmem_mknod+0x117/0x180 mm/shmem.c:3443\n shmem_create+0x34/0x40 mm/shmem.c:3497\n lookup_open fs/namei.c:3578 [inline]\n open_last_lookups fs/namei.c:3647 [inline]\n path_openat+0xdbc/0x1f00 fs/namei.c:3883\n do_filp_open+0xf7/0x200 fs/namei.c:3913\n do_sys_openat2+0xab/0x120 fs/open.c:1416\n do_sys_open fs/open.c:1431 [inline]\n __do_sys_openat fs/open.c:1447 [inline]\n __se_sys_openat fs/open.c:1442 [inline]\n __x64_sys_openat+0xf3/0x120 fs/open.c:1442\n x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nread to 0xffff888102eb3260 of 4 bytes by task 3498 on cpu 0:\n inode_get_ctime_nsec include/linux/fs.h:1623 [inline]\n inode_get_ctime include/linux/fs.h:1629 [inline]\n generic_fillattr+0x1dd/0x2f0 fs/stat.c:62\n shmem_getattr+0x17b/0x200 mm/shmem.c:1157\n vfs_getattr_nosec fs/stat.c:166 [inline]\n vfs_getattr+0x19b/0x1e0 fs/stat.c:207\n vfs_statx_path fs/stat.c:251 [inline]\n vfs_statx+0x134/0x2f0 fs/stat.c:315\n vfs_fstatat+0xec/0x110 fs/stat.c:341\n __do_sys_newfstatat fs/stat.c:505 [inline]\n __se_sys_newfstatat+0x58/0x260 fs/stat.c:499\n __x64_sys_newfstatat+0x55/0x70 fs/stat.c:499\n x64_sys_call+0x141f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:263\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nvalue changed: 0x2755ae53 -\u003e 0x27ee44d3\n\nReported by Kernel Concurrency Sanitizer on:\nCPU: 0 UID: 0 PID: 3498 Comm: udevd Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024\n==================================================================\n\nWhen calling generic_fillattr(), if you don\u0027t hold read lock, data-race\nwill occur in inode member variables, which can cause unexpected\nbehavior.\n\nSince there is no special protection when shmem_getattr() calls\ngeneric_fillattr(), data-race occurs by functions such as shmem_unlink()\nor shmem_mknod(). This can cause unexpected results, so commenting it out\nis not enough.\n\nTherefore, when calling generic_fillattr() from shmem_getattr(), it is\nappropriate to protect the inode using inode_lock_shared() and\ninode_unlock_shared() to prevent data-race.",
  "id": "GHSA-6f9r-4gpr-m3h8",
  "modified": "2024-11-13T21:30:32Z",
  "published": "2024-11-09T12:30:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-50228"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3d9528484480e8f4979b3a347930ed383be99f89"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7cc30ada84323be19395094d567579536e0d187e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/82cae1e30bd940253593c2d4f16d88343d1358f4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9fb9703cd43ee20a6de8ccdef991677b7274cec0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bda1a99a0dd644f31a87d636ac624eeb975cb65a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d949d1d14fa281ace388b1de978e8f2cd52875cf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/edd1f905050686fdc4cfe233d818469fdf7d5ff8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ffd56612566bc23877c8f45def2801f3324a222a"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}