CVE-2024-56549 (GCVE-0-2024-56549)
Vulnerability from cvelistv5
Published
2024-12-27 14:11
Modified
2026-10-15 21:41
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime are inconsistent, and the user-space invocation to anon_fd uses object->file. Following is the process that triggers the issue: [write fd] [umount] cachefiles_ondemand_fd_write_iter fscache_cookie_state_machine cachefiles_withdraw_cookie if (!file) return -ENOBUFS cachefiles_clean_up_object cachefiles_unmark_inode_in_use fput(object->file) object->file = NULL // file NULL pointer dereference! __cachefiles_write(..., file, ...) Fix this issue by add an additional reference count to the object->file before write/llseek, and decrement after it finished.
References
Impacted products
Vendor Product Version
Linux Linux Version: c8383054506c77b814489c09877b5db83fd4abf2
Version: c8383054506c77b814489c09877b5db83fd4abf2
Version: c8383054506c77b814489c09877b5db83fd4abf2
Version: c8383054506c77b814489c09877b5db83fd4abf2
Version: c8383054506c77b814489c09877b5db83fd4abf2
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