In sniff_min_interval_set():
if (val == 0 || val % 2 || val > hdev->sniff_max_interval)
return -EINVAL;
hci_dev_lock(hdev);
hdev->sniff_min_interval = val;
hci_dev_unlock(hdev);
In sniff_max_interval_set():
if (val == 0 || val % 2 || val < hdev->sniff_min_interval)
return -EINVAL;
hci_dev_lock(hdev);
hdev->sniff_max_interval = val;
hci_dev_unlock(hdev);
The atomicity violation occurs due to concurrent execution of set_min and
set_max funcs which may lead to inconsistent reads and writes of the min
value and the max value. The checks for value validity are ineffective as
the min/max values could change immediately after being checked, raising
the risk of the min value being greater than the max value and causing
invalid settings.
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: 71c3b60ec6d28 ("Bluetooth: Move BR/EDR debugfs file creation ...")
Cc: stable(a)vger.kernel.org
Reported-by: BassCheck <bass(a)buaa.edu.cn>
Signed-off-by: Gui-Dong Han <2045gemini(a)gmail.com>
---
net/bluetooth/hci_debugfs.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/net/bluetooth/hci_debugfs.c b/net/bluetooth/hci_debugfs.c
index 6b7741f6e95b..f032fdf8f481 100644
--- a/net/bluetooth/hci_debugfs.c
+++ b/net/bluetooth/hci_debugfs.c
@@ -566,11 +566,13 @@ DEFINE_DEBUGFS_ATTRIBUTE(idle_timeout_fops, idle_timeout_get,
static int sniff_min_interval_set(void *data, u64 val)
{
struct hci_dev *hdev = data;
-
- if (val == 0 || val % 2 || val > hdev->sniff_max_interval)
+
+ hci_dev_lock(hdev);
+ if (val == 0 || val % 2 || val > hdev->sniff_max_interval) {
+ hci_dev_unlock(hdev);
return -EINVAL;
+ }
- hci_dev_lock(hdev);
hdev->sniff_min_interval = val;
hci_dev_unlock(hdev);
@@ -594,11 +596,13 @@ DEFINE_DEBUGFS_ATTRIBUTE(sniff_min_interval_fops, sniff_min_interval_get,
static int sniff_max_interval_set(void *data, u64 val)
{
struct hci_dev *hdev = data;
-
- if (val == 0 || val % 2 || val < hdev->sniff_min_interval)
+
+ hci_dev_lock(hdev);
+ if (val == 0 || val % 2 || val < hdev->sniff_min_interval) {
+ hci_dev_unlock(hdev);
return -EINVAL;
+ }
- hci_dev_lock(hdev);
hdev->sniff_max_interval = val;
hci_dev_unlock(hdev);
--
2.34.1
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 which may lead to inconsistent reads and writes of the min
value and the max value. The checks for value validity are ineffective as
the min/max values could change immediately after being checked, raising
the risk of the min value being greater than the max value and causing
invalid settings.
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: 18f81241b74fb ("Bluetooth: Move {min,max}_key_size debugfs ...")
Cc: stable(a)vger.kernel.org
Reported-by: BassCheck <bass(a)buaa.edu.cn>
Signed-off-by: Gui-Dong Han <2045gemini(a)gmail.com>
---
net/bluetooth/hci_debugfs.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/net/bluetooth/hci_debugfs.c b/net/bluetooth/hci_debugfs.c
index 6b7741f6e95b..3ffbf3f25363 100644
--- a/net/bluetooth/hci_debugfs.c
+++ b/net/bluetooth/hci_debugfs.c
@@ -1045,11 +1045,13 @@ DEFINE_DEBUGFS_ATTRIBUTE(adv_max_interval_fops, adv_max_interval_get,
static int min_key_size_set(void *data, u64 val)
{
struct hci_dev *hdev = data;
-
- if (val > hdev->le_max_key_size || val < SMP_MIN_ENC_KEY_SIZE)
+
+ hci_dev_lock(hdev);
+ if (val > hdev->le_max_key_size || val < SMP_MIN_ENC_KEY_SIZE) {
+ hci_dev_unlock(hdev);
return -EINVAL;
+ }
- hci_dev_lock(hdev);
hdev->le_min_key_size = val;
hci_dev_unlock(hdev);
@@ -1073,11 +1075,13 @@ DEFINE_DEBUGFS_ATTRIBUTE(min_key_size_fops, min_key_size_get,
static int max_key_size_set(void *data, u64 val)
{
struct hci_dev *hdev = data;
-
- if (val > SMP_MAX_ENC_KEY_SIZE || val < hdev->le_min_key_size)
+
+ hci_dev_lock(hdev);
+ if (val > SMP_MAX_ENC_KEY_SIZE || val < hdev->le_min_key_size) {
+ hci_dev_unlock(hdev);
return -EINVAL;
+ }
- hci_dev_lock(hdev);
hdev->le_max_key_size = val;
hci_dev_unlock(hdev);
--
2.34.1
From: Guo Ren <guoren(a)linux.alibaba.com>
In COMPAT mode, the STACK_TOP is 0x80000000, but the TASK_SIZE is
0x7fff000. When the user stack is upon 0x7fff000, it will cause a user
segment fault. Sometimes, it would cause boot failure when the whole
rootfs is rv32.
Freeing unused kernel image (initmem) memory: 2236K
Run /sbin/init as init process
Starting init: /sbin/init exists but couldn't execute it (error -14)
Run /etc/init as init process
...
Cc: stable(a)vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren(a)linux.alibaba.com>
Signed-off-by: Guo Ren <guoren(a)kernel.org>
---
arch/riscv/include/asm/pgtable.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index ab00235b018f..74ffb2178f54 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
#ifdef CONFIG_COMPAT
-#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE)
+#define TASK_SIZE_32 (_AC(0x80000000, UL))
#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
#else
--
2.40.1
Current implementation blocks the running operations when Plug-out and
Plug-In is performed continuously, process gets stuck in
dwc3_thread_interrupt().
Code Flow:
CPU1
->Gadget_start
->dwc3_interrupt
->dwc3_thread_interrupt
->dwc3_process_event_buf
->dwc3_process_event_entry
->dwc3_endpoint_interrupt
->dwc3_ep0_interrupt
->dwc3_ep0_inspect_setup
->dwc3_ep0_stall_and_restart
By this time if pending_list is not empty, it will get the next request
on the given list and calls dwc3_gadget_giveback which will unmap request
and call its complete() callback to notify upper layers that it has
completed. Currently dwc3_gadget_giveback status is set to -ECONNRESET,
whereas it should be -ESHUTDOWN based on condition if not dwc->connected
is true.
Cc: <stable(a)vger.kernel.org>
Fixes: d742220b3577 ("usb: dwc3: ep0: giveback requests on stall_and_restart")
Signed-off-by: Uttkarsh Aggarwal <quic_uaggarwa(a)quicinc.com>
---
Changes in v2:
Added dwc->connected check to set status either -ESHUTDOWN and -ECONNRESET
in dwc3_gadget_giveback.
Link to v1:
https://lore.kernel.org/all/20231122091127.3636-1-quic_uaggarwa@quicinc.com…
drivers/usb/dwc3/ep0.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index b94243237293..816b8eea73d6 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -238,7 +238,10 @@ void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
struct dwc3_request *req;
req = next_request(&dep->pending_list);
- dwc3_gadget_giveback(dep, req, -ECONNRESET);
+ if (!dwc->connected)
+ dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
+ else
+ dwc3_gadget_giveback(dep, req, -ECONNRESET);
}
dwc->eps[0]->trb_enqueue = 0;
--
2.17.1