[REJECTED CVE] A NULL pointer dereference vulnerability has been identified in the Linux Kernel's ext4 filesystem. The issue occurs during concurrent write operations with inline data, where an ext4_force_shutdown is triggered due to inconsistencies like "block bitmap and bg descriptor inconsistent." This shutdown disrupts inline data handling, failing to restore the EXT4_STATE_MAY_INLINE_DATA flag. As a result, subsequent operations, such as in ext4_da_write_end, may attempt to dereference an unset page folio private pointer, leading to potential kernel crashes.

Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.

In the Linux kernel, the following vulnerability has been resolved: ext4: sanity check for NULL pointer after ext4_force_shutdown Test case: 2 threads write short inline data to a file. In ext4_page_mkwrite the resulting inline data is converted. Handling ext4_grp_locked_error with description "block bitmap and bg descriptor inconsistent: X vs Y free clusters" calls ext4_force_shutdown. The conversion clears EXT4_STATE_MAY_INLINE_DATA but fails for ext4_destroy_inline_data_nolock and ext4_mark_iloc_dirty due to ext4_forced_shutdown. The restoration of inline data fails for the same reason not setting EXT4_STATE_MAY_INLINE_DATA. Without the flag set a regular process path in ext4_da_write_end follows trying to dereference page folio private pointer that has not been set. The fix calls early return with -EIO error shall the pointer to private be NULL. Sample crash report: Unable to handle kernel paging request at virtual address dfff800000000004 KASAN: null-ptr-deref in range [0x0...

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

Security update for the Linux Kernel

ELSA-2025-6966: kernel security update (MODERATE)