In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix UAF in __close_file_table_ids
A use-after-free is possible if one thread destroys the file via __ksmbd_close_fd while another thread holds a reference to it. The existing checks on fp->refcount are not sufficient to prevent this.
The fix takes ft->lock around the section which removes the file from the file table. This prevents two threads acquiring the same file pointer via __close_file_table_ids, as well as the other functions which retrieve a file from the IDR and which already use this same lock.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 5.15 | 6.6.91 |
| linux / linux_kernel | 6.7 | 6.12.29 |
| linux / linux_kernel | 6.13 | 6.14.7 |
| linux / linux_kernel | 6.15-rc1 | 6.15-rc1.x |
| linux / linux_kernel | 6.15-rc2 | 6.15-rc2.x |
| linux / linux_kernel | 6.15-rc3 | 6.15-rc3.x |
| linux / linux_kernel | 6.15-rc4 | 6.15-rc4.x |
| linux / linux_kernel | 6.15-rc5 | 6.15-rc5.x |