Bug 2429096 (CVE-2025-68820)

Summary: CVE-2025-68820 kernel: ext4: xattr: fix null pointer deref in ext4_raw_inode()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Version: unspecifiedKeywords: Security
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OS: Linux   
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A NULL pointer dereference vulnerability was found in the Linux kernel's ext4 filesystem extended attribute handling. When ext4_get_inode_loc() fails with an error such as -EFSCORRUPTED, the iloc.bh buffer head remains NULL. The ext4_xattr_inode_dec_ref_all() function lacks error checking and proceeds to call ext4_raw_inode() with the NULL buffer, causing a kernel crash.
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Description OSIDB Bzimport 2026-01-13 16:06:28 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ext4: xattr: fix null pointer deref in ext4_raw_inode()

If ext4_get_inode_loc() fails (e.g. if it returns -EFSCORRUPTED),
iloc.bh will remain set to NULL. Since ext4_xattr_inode_dec_ref_all()
lacks error checking, this will lead to a null pointer dereference
in ext4_raw_inode(), called right after ext4_get_inode_loc().

Found by Linux Verification Center (linuxtesting.org) with SVACE.
Comment 1 Jon Moroney 2026-01-14 23:45:14 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026011315-CVE-2025-68820-7a4f@gregkh/T