kernel/linux.git/net/bluetooth/hci_debugfs.c, branch v6.6.133

Bluetooth: Fix TOCTOU in HCI debugfs implementation

2024-04-10T14:35:49+00:00

commit 7835fcfd132eb88b87e8eb901f88436f63ab60f7 upstream. struct hci_dev members conn_info_max_age, conn_info_min_age, le_conn_max_interval, le_conn_min_interval, le_adv_max_interval, and le_adv_min_interval can be modified from the HCI core code, as well through debugfs. The debugfs implementation, that's only available to privileged users, will check for boundaries, making sure that the minimum value being set is strictly above the maximum value that already exists, and vice-versa. However, as both minimum and maximum values can be changed concurrently to us modifying them, we need to make sure that the value we check is the value we end up using. For example, with ->conn_info_max_age set to 10, conn_info_min_age_set() gets called from vfs handlers to set conn_info_min_age to 8. In conn_info_min_age_set(), this goes through: if (val == 0 || val > hdev->conn_info_max_age) return -EINVAL; Concurrently, conn_info_max_age_set() gets called to set to set the conn_info_max_age to 7: if (val == 0 || val > hdev->conn_info_max_age) return -EINVAL; That check will also pass because we used the old value (10) for conn_info_max_age. After those checks that both passed, the struct hci_dev access is mutex-locked, disabling concurrent access, but that does not matter because the invalid value checks both passed, and we'll end up with conn_info_min_age = 8 and conn_info_max_age = 7 To fix this problem, we need to lock the structure access before so the check and assignment are not interrupted. This fix was originally devised by the BassCheck[1] team, and considered the problem to be an atomicity one. This isn't the case as there aren't any concerns about the variable changing while we check it, but rather after we check it parallel to another change. This patch fixes CVE-2024-24858 and CVE-2024-24857. [1] https://sites.google.com/view/basscheck/ Co-developed-by: Gui-Dong Han <2045gemini@gmail.com> Signed-off-by: Gui-Dong Han <2045gemini@gmail.com> Link: https://lore.kernel.org/linux-bluetooth/20231222161317.6255-1-2045gemini@gmail.com/ Link: https://nvd.nist.gov/vuln/detail/CVE-2024-24858 Link: https://lore.kernel.org/linux-bluetooth/20231222162931.6553-1-2045gemini@gmail.com/ Link: https://lore.kernel.org/linux-bluetooth/20231222162310.6461-1-2045gemini@gmail.com/ Link: https://nvd.nist.gov/vuln/detail/CVE-2024-24857 Fixes: 31ad169148df ("Bluetooth: Add conn info lifetime parameters to debugfs") Fixes: 729a1051da6f ("Bluetooth: Expose default LE advertising interval via debugfs") Fixes: 71c3b60ec6d2 ("Bluetooth: Move BR/EDR debugfs file creation into hci_debugfs.c") Signed-off-by: Bastien Nocera Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: Fix atomicity violation in {min,max}_key_size_set

2024-01-25T23:35:46+00:00

commit da9065caa594d19b26e1a030fd0cc27bd365d685 upstream. In min_key_size_set(): if (val > hdev->le_max_key_size || val < SMP_MIN_ENC_KEY_SIZE) return -EINVAL; hci_dev_lock(hdev); hdev->le_min_key_size = val; hci_dev_unlock(hdev); In max_key_size_set(): if (val > SMP_MAX_ENC_KEY_SIZE || val < hdev->le_min_key_size) return -EINVAL; hci_dev_lock(hdev); hdev->le_max_key_size = val; hci_dev_unlock(hdev); The atomicity violation occurs due to concurrent execution of set_min and set_max funcs.Consider a scenario where setmin writes a new, valid 'min' value, and concurrently, setmax writes a value that is greater than the old 'min' but smaller than the new 'min'. In this case, setmax might check against the old 'min' value (before acquiring the lock) but write its value after the 'min' has been updated by setmin. This leads to a situation where the 'max' value ends up being smaller than the 'min' value, which is an inconsistency. This possible bug is found by an experimental static analysis tool developed by our team, BassCheck[1]. This tool analyzes the locking APIs to extract function pairs that can be concurrently executed, and then analyzes the instructions in the paired functions to identify possible concurrency bugs including data races and atomicity violations. The above possible bug is reported when our tool analyzes the source code of Linux 5.17. To resolve this issue, it is suggested to encompass the validity checks within the locked sections in both set_min and set_max funcs. The modification ensures that the validation of 'val' against the current min/max values is atomic, thus maintaining the integrity of the settings. With this patch applied, our tool no longer reports the bug, with the kernel configuration allyesconfig for x86_64. Due to the lack of associated hardware, we cannot test the patch in runtime testing, and just verify it according to the code logic. [1] https://sites.google.com/view/basscheck/ Fixes: 18f81241b74f ("Bluetooth: Move {min,max}_key_size debugfs ...") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han <2045gemini@gmail.com> Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_debugfs: Use kstrtobool() instead of strtobool()

2023-08-11T18:47:44+00:00

strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. While at it, include the corresponding header file () Signed-off-by: Christophe JAILLET Signed-off-by: Luiz Augusto von Dentz

Bluetooth: fix inconsistent indenting

2023-04-24T05:02:14+00:00

Fixed a wrong indentation before "return".This line uses a 7 space indent instead of a tab. Signed-off-by: Lanzhe Li Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_sync: Fix not able to set force_static_address

2022-12-12T22:19:23+00:00

force_static_address shall be writable while hdev is initing but is not considered powered yet since the static address is written only when powered. Signed-off-by: Luiz Augusto von Dentz Tested-by: Brian Gix

Bluetooth: hci_debugfs: Fix not checking conn->debugfs

2022-09-21T22:01:21+00:00

hci_debugfs_create_conn shall check if conn->debugfs has already been created and don't attempt to overwrite it. Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Move all debugfs handling to hci_debugfs.c

2021-09-22T14:17:13+00:00

This moves hci_debugfs_create_basic to hci_debugfs.c which is where all the others debugfs entries are handled. Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Marcel Holtmann

Bluetooth: use inclusive language when filtering devices

2021-06-26T05:12:44+00:00

This patch replaces some non-inclusive terms based on the appropriate language mapping table compiled by the Bluetooth SIG: https://specificationrefs.bluetooth.com/language-mapping/Appropriate_Language_Mapping_Table.pdf Specifically, these terms are replaced: blacklist -> reject list whitelist -> accept list Signed-off-by: Archie Pusaka Reviewed-by: Miao-chen Chou Signed-off-by: Marcel Holtmann

Bluetooth: Coding style fix

2021-04-02T09:03:04+00:00

1. Add space when needed; 2. Block comments style fix; 3. Move open brace '{' following function definitions to the next line; 4. Remove unnecessary braces '{}' for single statement blocks. Signed-off-by: Meng Yu Signed-off-by: Marcel Holtmann

Bluetooth: fix coccicheck warnings debugfs

2021-01-29T15:51:35+00:00

Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for debugfs files. Reported-by: Abaci Robot Signed-off-by: Jiapeng Zhong Signed-off-by: Marcel Holtmann