CVE-2024-47699

Summary

In the Linux kernel, the following vulnerability has been resolved:

nilfs2: fix potential null-ptr-deref in nilfs_btree_insert()

Patch series "nilfs2: fix potential issues with empty b-tree nodes".

This series addresses three potential issues with empty b-tree nodes that can occur with corrupted filesystem images, including one recently discovered by syzbot.

This patch (of 3):

If a b-tree is broken on the device, and the b-tree height is greater than 2 (the level of the root node is greater than 1) even if the number of child nodes of the b-tree root is 0, a NULL pointer dereference occurs in nilfs_btree_prepare_insert(), which is called from nilfs_btree_insert().

This is because, when the number of child nodes of the b-tree root is 0, nilfs_btree_do_lookup() does not set the block buffer head in any of path[x].bp_bh, leaving it as the initial value of NULL, but if the level of the b-tree root node is greater than 1, nilfs_btree_get_nonroot_node(), which accesses the buffer memory of path[x].bp_bh, is called.

Fix this issue by adding a check to nilfs_btree_root_broken(), which performs sanity checks when reading the root node from the device, to detect this inconsistency.

Thanks to Lizhi Xu for trying to solve the bug and clarifying the cause early on.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 2b78e9df10fb7f4e9d3d7a18417dd72fbbc1dfd0affected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 1d94dbdfbb64cc48d10dec65cc3c4fbf2497b343affected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 24bf40740a3da6b4056721da34997ae6938f3da1affected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 73d23ecf234b7a6d47fb883f2dabe10e3230b31daffected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < f68523e0f26faade18833fbef577a4295d8e2c94affected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 21839b6fbc3c41b3e374ecbdb0cabbbb2c53cf34affected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < db73500d3f0e558eb642aae1d4782e7726b4a03faffected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 3644554d308ddf2669e459a1551a7edf60b2d62baffected
LinuxLinux17c76b0104e4a6513983777e1a17e0297a12b0c4 < 9403001ad65ae4f4c5de368bdda3a0636b51d51aaffected
LinuxLinux2.6.30affected
LinuxLinux0 < 2.6.30unaffected
LinuxLinux4.19.323 <= 4.19.*unaffected
LinuxLinux5.4.285 <= 5.4.*unaffected
LinuxLinux5.10.227 <= 5.10.*unaffected
LinuxLinux5.15.168 <= 5.15.*unaffected
LinuxLinux6.1.113 <= 6.1.*unaffected
LinuxLinux6.6.54 <= 6.6.*unaffected
LinuxLinux6.10.13 <= 6.10.*unaffected
LinuxLinux6.11.2 <= 6.11.*unaffected
LinuxLinux6.12 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

Additional References

References