linux/net/bluetooth/hci_debugfs.c

1395 lines
33 KiB

Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Store Resolv list size When the controller supports the Read LE Resolv List size feature, the maximum list size are read and now stored. Before patch: < HCI Command: LE Read White List... (0x08|0x000f) plen 0 #55 [hci0] 17.979791 > HCI Event: Command Complete (0x0e) plen 5 #56 [hci0] 17.980629 LE Read White List Size (0x08|0x000f) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Clear White List (0x08|0x0010) plen 0 #57 [hci0] 17.980786 > HCI Event: Command Complete (0x0e) plen 4 #58 [hci0] 17.981627 LE Clear White List (0x08|0x0010) ncmd 1 Status: Success (0x00) < HCI Command: LE Read Maximum Dat.. (0x08|0x002f) plen 0 #59 [hci0] 17.981786 > HCI Event: Command Complete (0x0e) plen 12 #60 [hci0] 17.982636 LE Read Maximum Data Length (0x08|0x002f) ncmd 1 Status: Success (0x00) Max TX octets: 251 Max TX time: 17040 Max RX octets: 251 Max RX time: 17040 After patch: < HCI Command: LE Read White List... (0x08|0x000f) plen 0 #55 [hci0] 13.338168 > HCI Event: Command Complete (0x0e) plen 5 #56 [hci0] 13.338842 LE Read White List Size (0x08|0x000f) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Clear White List (0x08|0x0010) plen 0 #57 [hci0] 13.339029 > HCI Event: Command Complete (0x0e) plen 4 #58 [hci0] 13.339939 LE Clear White List (0x08|0x0010) ncmd 1 Status: Success (0x00) < HCI Command: LE Read Resolving L.. (0x08|0x002a) plen 0 #59 [hci0] 13.340152 > HCI Event: Command Complete (0x0e) plen 5 #60 [hci0] 13.340952 LE Read Resolving List Size (0x08|0x002a) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Read Maximum Dat.. (0x08|0x002f) plen 0 #61 [hci0] 13.341180 > HCI Event: Command Complete (0x0e) plen 12 #62 [hci0] 13.341898 LE Read Maximum Data Length (0x08|0x002f) ncmd 1 Status: Success (0x00) Max TX octets: 251 Max TX time: 17040 Max RX octets: 251 Max RX time: 17040 Signed-off-by: Ankit Navik <ankit.p.navik@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2018-06-29 12:12:50 +05:30
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix TOCTOU in HCI debugfs implementation 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 <hadess@hadess.net> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2024-03-27 15:24:56 +01:00
Bluetooth: Fix atomicity violation in {min,max}_key_size_set 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 <luiz.von.dentz@intel.com>
2023-12-22 23:12:41 +08:00
Bluetooth: Fix atomicity violation in {min,max}_key_size_set 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 <luiz.von.dentz@intel.com>
2023-12-22 23:12:41 +08:00
Bluetooth: Store Resolv list size When the controller supports the Read LE Resolv List size feature, the maximum list size are read and now stored. Before patch: < HCI Command: LE Read White List... (0x08|0x000f) plen 0 #55 [hci0] 17.979791 > HCI Event: Command Complete (0x0e) plen 5 #56 [hci0] 17.980629 LE Read White List Size (0x08|0x000f) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Clear White List (0x08|0x0010) plen 0 #57 [hci0] 17.980786 > HCI Event: Command Complete (0x0e) plen 4 #58 [hci0] 17.981627 LE Clear White List (0x08|0x0010) ncmd 1 Status: Success (0x00) < HCI Command: LE Read Maximum Dat.. (0x08|0x002f) plen 0 #59 [hci0] 17.981786 > HCI Event: Command Complete (0x0e) plen 12 #60 [hci0] 17.982636 LE Read Maximum Data Length (0x08|0x002f) ncmd 1 Status: Success (0x00) Max TX octets: 251 Max TX time: 17040 Max RX octets: 251 Max RX time: 17040 After patch: < HCI Command: LE Read White List... (0x08|0x000f) plen 0 #55 [hci0] 13.338168 > HCI Event: Command Complete (0x0e) plen 5 #56 [hci0] 13.338842 LE Read White List Size (0x08|0x000f) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Clear White List (0x08|0x0010) plen 0 #57 [hci0] 13.339029 > HCI Event: Command Complete (0x0e) plen 4 #58 [hci0] 13.339939 LE Clear White List (0x08|0x0010) ncmd 1 Status: Success (0x00) < HCI Command: LE Read Resolving L.. (0x08|0x002a) plen 0 #59 [hci0] 13.340152 > HCI Event: Command Complete (0x0e) plen 5 #60 [hci0] 13.340952 LE Read Resolving List Size (0x08|0x002a) ncmd 1 Status: Success (0x00) Size: 25 < HCI Command: LE Read Maximum Dat.. (0x08|0x002f) plen 0 #61 [hci0] 13.341180 > HCI Event: Command Complete (0x0e) plen 12 #62 [hci0] 13.341898 LE Read Maximum Data Length (0x08|0x002f) ncmd 1 Status: Success (0x00) Max TX octets: 251 Max TX time: 17040 Max RX octets: 251 Max RX time: 17040 Signed-off-by: Ankit Navik <ankit.p.navik@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2018-06-29 12:12:50 +05:30