Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on node footer in {read,write}_end_io -----------[ cut here ]------------ kernel BUG at fs/f2fs/data.c:358! Call Trace: <IRQ> blk_update_request+0x5eb/0xe70 block/blk-mq.c:987 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149 blk_complete_reqs block/blk-mq.c:1224 [inline] blk_done_softirq+0x107/0x160 block/blk-mq.c:1229 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 </IRQ> In f2fs_write_end_io(), it detects there is inconsistency in between node page index (nid) and footer.nid of node page. If footer of node page is corrupted in fuzzed image, then we load corrupted node page w/ async method, e.g. f2fs_ra_node_pages() or f2fs_ra_node_page(), in where we won't do sanity check on node footer, once node page becomes dirty, we will encounter this bug after node page writeback.

Affected Products 2

References 3

• git.kernel.org https://git.kernel.org/stable/c/50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4
  Patch
• git.kernel.org https://git.kernel.org/stable/c/855c54f1803e3ebc613677b4f389c7f92656a1fc
  Patch
• git.kernel.org https://git.kernel.org/stable/c/c386753db52b3a80afa6612bfdcb925aa5ca260f
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4
  Patch
• git.kernel.org https://git.kernel.org/stable/c/855c54f1803e3ebc613677b4f389c7f92656a1fc
  Patch
• git.kernel.org https://git.kernel.org/stable/c/c386753db52b3a80afa6612bfdcb925aa5ca260f
  Patch