usb: gadget: f_tcm: fix deadlock in usbg_make_tpg()

Summary

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_tcm: fix deadlock in usbg_make_tpg() usbg_make_tpg() held dep_lock while calling configfs_depend_item_unlocked(), which acquires the configfs root inode lock when operating across subsystems. This creates a circular lock dependency with configfs_rmdir(): dep_lock -> configfs root inode lock -> su_mutex -> dep_lock In usbg_make_tpg(), dep_lock only serialized the read of opts->ready, which is a monotonic flag that transitions from false to true exactly once (in tcm_set_name()) and never reverts. Remove dep_lock from usbg_make_tpg() entirely and use READ_ONCE/WRITE_ONCE to access opts->ready locklessly instead.

Timeline

1. Sep 24, 2026, 3:10 PM UTCCVE published
2. Oct 19, 2026, 9:07 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in abad5daa41cf5d0a0a9cba0397d3a0e7f11e0277; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in 3639438a4c83ffc2e564c8c010b92137c5d11cfa; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in 78a14ea2284825055ab6c2a1f3489510f560f3a2; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in eef3e62f90d86c1c5651742f84ecc9db1814a893; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in f81a2da137b029a282b9bc64d2f267d242948659; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in 6bcd9ee6ad6989d1d85a7459687e45b7ad7568d9; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in d90b0f90e30cd59b36005a4016b15cf02bcd7fb2; From 4bb8548df632187d5db50878e71804af5f7c51ad · fixed in 9dbf74f4022f80f7669d2b3c22c5deb46c1b5674

• Linux Linux

  4.5

• KernelLinux

  From 4.5.0 · fixed in 5.10.270; From 5.11.0 · fixed in 5.15.221; From 5.16.0 · fixed in 6.1.188; From 6.2.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.109; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4

References 8