Hello I found a bug in latest upstream titled "divide error in
alauda_transport", and maybe is realted with usb.
I comfired in the latest upstream the poc tree can trigger the issue.
If you fix this issue, please add the following tag to the commit:
Reported-by: xingwei lee <[email protected]>
Reported-by: yue sun <[email protected]>
kernel: upstream 9187210eee7d87eea37b45ea93454a88681894a4
config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=1c6662240382da2
with KASAN enabled
compiler: gcc (Debian 12.2.0-14) 12.2.0
divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 2 PID: 8229 Comm: usb-storage Not tainted 6.8.0-05202-g9187210eee7d #20
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.2-1.fc38 04/01/2014
RIP: 0010:alauda_read_data drivers/usb/storage/alauda.c:954 [inline]
RIP: 0010:alauda_transport+0xcaf/0x3830 drivers/usb/storage/alauda.c:1184
Code: 24 18 01 00 00 00 00 00 00 48 c1 e8 03 85 f6 48 89 44 24 30 0f
84 af 01 00 00 4c 89 54 24 70 4d 89 dc 31 d2 44 89 f0 4c 89 e7 <f7> 74
24 48 89 c5 41 89 d5 89 ee e8 e1 c1 ff ff 66 44 30
RSP: 0018:ffffc90010ccfa60 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024f12cb8
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10049e25ad
R10: ffff888024f13088 R11: ffff888024f12cb8 R12: ffff888024f12cb8
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055679a87dd88 CR3: 000000000c774000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
usb_stor_invoke_transport+0xea/0x13d0 drivers/usb/storage/transport.c:611
usb_stor_control_thread+0x5d6/0x980 drivers/usb/storage/usb.c:368
kthread+0x2eb/0x3d0 kernel/kthread.c:388
ret_from_fork+0x2f/0x70 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:alauda_read_data drivers/usb/storage/alauda.c:954 [inline]
RIP: 0010:alauda_transport+0xcaf/0x3830 drivers/usb/storage/alauda.c:1184
Code: 24 18 01 00 00 00 00 00 00 48 c1 e8 03 85 f6 48 89 44 24 30 0f
84 af 01 00 00 4c 89 54 24 70 4d 89 dc 31 d2 44 89 f0 4c 89 e7 <f7> 74
24 48 89 c5 41 89 d5 89 ee e8 e1 c1 ff ff 66 44 30
RSP: 0018:ffffc90010ccfa60 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888024f12cb8
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10049e25ad
R10: ffff888024f13088 R11: ffff888024f12cb8 R12: ffff888024f12cb8
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055679a875010 CR3: 0000000023588000 CR4: 0000000000750ef0
PKRU: 55555554
----------------
Code disassembly (best guess):
0: 24 18 and $0x18,%al
2: 01 00 add %eax,(%rax)
4: 00 00 add %al,(%rax)
6: 00 00 add %al,(%rax)
8: 00 48 c1 add %cl,-0x3f(%rax)
b: e8 03 85 f6 48 call 0x48f68513
10: 89 44 24 30 mov %eax,0x30(%rsp)
14: 0f 84 af 01 00 00 je 0x1c9
1a: 4c 89 54 24 70 mov %r10,0x70(%rsp)
1f: 4d 89 dc mov %r11,%r12
22: 31 d2 xor %edx,%edx
24: 44 89 f0 mov %r14d,%eax
27: 4c 89 e7 mov %r12,%rdi
* 2a: f7 74 24 48 divl 0x48(%rsp) <-- trapping instruction
2e: 89 c5 mov %eax,%ebp
30: 41 89 d5 mov %edx,%r13d
33: 89 ee mov %ebp,%esi
35: e8 e1 c1 ff ff call 0xffffc21b
3a: 66 data16
3b: 44 rex.R
3c: 30 .byte 0x30
=* repro.c =*
#define _GNU_SOURCE
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#include <linux/usb/ch9.h>
static unsigned long long procid;
static void sleep_ms(uint64_t ms) {
usleep(ms * 1000);
}
#define MAX_FDS 30
#define USB_MAX_IFACE_NUM 4
#define USB_MAX_EP_NUM 32
#define USB_MAX_FDS 6
struct usb_endpoint_index {
struct usb_endpoint_descriptor desc;
int handle;
};
struct usb_iface_index {
struct usb_interface_descriptor* iface;
uint8_t bInterfaceNumber;
uint8_t bAlternateSetting;
uint8_t bInterfaceClass;
struct usb_endpoint_index eps[USB_MAX_EP_NUM];
int eps_num;
};
struct usb_device_index {
struct usb_device_descriptor* dev;
struct usb_config_descriptor* config;
uint8_t bDeviceClass;
uint8_t bMaxPower;
int config_length;
struct usb_iface_index ifaces[USB_MAX_IFACE_NUM];
int ifaces_num;
int iface_cur;
};
struct usb_info {
int fd;
struct usb_device_index index;
};
static struct usb_info usb_devices[USB_MAX_FDS];
static struct usb_device_index* lookup_usb_index(int fd) {
for (int i = 0; i < USB_MAX_FDS; i++) {
if (__atomic_load_n(&usb_devices[i].fd, __ATOMIC_ACQUIRE) == fd)
return &usb_devices[i].index;
}
return NULL;
}
static int usb_devices_num;
static bool parse_usb_descriptor(const char* buffer,
size_t length,
struct usb_device_index* index) {
if (length < sizeof(*index->dev) + sizeof(*index->config))
return false;
memset(index, 0, sizeof(*index));
index->dev = (struct usb_device_descriptor*)buffer;
index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev));
index->bDeviceClass = index->dev->bDeviceClass;
index->bMaxPower = index->config->bMaxPower;
index->config_length = length - sizeof(*index->dev);
index->iface_cur = -1;
size_t offset = 0;
while (true) {
if (offset + 1 >= length)
break;
uint8_t desc_length = buffer[offset];
uint8_t desc_type = buffer[offset + 1];
if (desc_length <= 2)
break;
if (offset + desc_length > length)
break;
if (desc_type == USB_DT_INTERFACE &&
index->ifaces_num < USB_MAX_IFACE_NUM) {
struct usb_interface_descriptor* iface =
(struct usb_interface_descriptor*)(buffer + offset);
index->ifaces[index->ifaces_num].iface = iface;
index->ifaces[index->ifaces_num].bInterfaceNumber =
iface->bInterfaceNumber;
index->ifaces[index->ifaces_num].bAlternateSetting =
iface->bAlternateSetting;
index->ifaces[index->ifaces_num].bInterfaceClass = iface->bInterfaceClass;
index->ifaces_num++;
}
if (desc_type == USB_DT_ENDPOINT && index->ifaces_num > 0) {
struct usb_iface_index* iface = &index->ifaces[index->ifaces_num - 1];
if (iface->eps_num < USB_MAX_EP_NUM) {
memcpy(&iface->eps[iface->eps_num].desc, buffer + offset,
sizeof(iface->eps[iface->eps_num].desc));
iface->eps_num++;
}
}
offset += desc_length;
}
return true;
}
static struct usb_device_index* add_usb_index(int fd,
const char* dev,
size_t dev_len) {
int i = __atomic_fetch_add(&usb_devices_num, 1, __ATOMIC_RELAXED);
if (i >= USB_MAX_FDS)
return NULL;
if (!parse_usb_descriptor(dev, dev_len, &usb_devices[i].index))
return NULL;
__atomic_store_n(&usb_devices[i].fd, fd, __ATOMIC_RELEASE);
return &usb_devices[i].index;
}
struct vusb_connect_string_descriptor {
uint32_t len;
char* str;
} __attribute__((packed));
struct vusb_connect_descriptors {
uint32_t qual_len;
char* qual;
uint32_t bos_len;
char* bos;
uint32_t strs_len;
struct vusb_connect_string_descriptor strs[0];
} __attribute__((packed));
static const char default_string[] = {8, USB_DT_STRING, 's', 0, 'y', 0, 'z', 0};
static const char default_lang_id[] = {4, USB_DT_STRING, 0x09, 0x04};
static bool lookup_connect_response_in(
int fd,
const struct vusb_connect_descriptors* descs,
const struct usb_ctrlrequest* ctrl,
struct usb_qualifier_descriptor* qual,
char** response_data,
uint32_t* response_length) {
struct usb_device_index* index = lookup_usb_index(fd);
uint8_t str_idx;
if (!index)
return false;
switch (ctrl->bRequestType & USB_TYPE_MASK) {
case USB_TYPE_STANDARD:
switch (ctrl->bRequest) {
case USB_REQ_GET_DESCRIPTOR:
switch (ctrl->wValue >> 8) {
case USB_DT_DEVICE:
*response_data = (char*)index->dev;
*response_length = sizeof(*index->dev);
return true;
case USB_DT_CONFIG:
*response_data = (char*)index->config;
*response_length = index->config_length;
return true;
case USB_DT_STRING:
str_idx = (uint8_t)ctrl->wValue;
if (descs && str_idx < descs->strs_len) {
*response_data = descs->strs[str_idx].str;
*response_length = descs->strs[str_idx].len;
return true;
}
if (str_idx == 0) {
*response_data = (char*)&default_lang_id[0];
*response_length = default_lang_id[0];
return true;
}
*response_data = (char*)&default_string[0];
*response_length = default_string[0];
return true;
case USB_DT_BOS:
*response_data = descs->bos;
*response_length = descs->bos_len;
return true;
case USB_DT_DEVICE_QUALIFIER:
if (!descs->qual) {
qual->bLength = sizeof(*qual);
qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
qual->bcdUSB = index->dev->bcdUSB;
qual->bDeviceClass = index->dev->bDeviceClass;
qual->bDeviceSubClass = index->dev->bDeviceSubClass;
qual->bDeviceProtocol = index->dev->bDeviceProtocol;
qual->bMaxPacketSize0 = index->dev->bMaxPacketSize0;
qual->bNumConfigurations = index->dev->bNumConfigurations;
qual->bRESERVED = 0;
*response_data = (char*)qual;
*response_length = sizeof(*qual);
return true;
}
*response_data = descs->qual;
*response_length = descs->qual_len;
return true;
default:
break;
}
break;
default:
break;
}
break;
default:
break;
}
return false;
}
typedef bool (*lookup_connect_out_response_t)(
int fd,
const struct vusb_connect_descriptors* descs,
const struct usb_ctrlrequest* ctrl,
bool* done);
static bool lookup_connect_response_out_generic(
int fd,
const struct vusb_connect_descriptors* descs,
const struct usb_ctrlrequest* ctrl,
bool* done) {
switch (ctrl->bRequestType & USB_TYPE_MASK) {
case USB_TYPE_STANDARD:
switch (ctrl->bRequest) {
case USB_REQ_SET_CONFIGURATION:
*done = true;
return true;
default:
break;
}
break;
}
return false;
}
struct vusb_descriptor {
uint8_t req_type;
uint8_t desc_type;
uint32_t len;
char data[0];
} __attribute__((packed));
struct vusb_descriptors {
uint32_t len;
struct vusb_descriptor* generic;
struct vusb_descriptor* descs[0];
} __attribute__((packed));
struct vusb_response {
uint8_t type;
uint8_t req;
uint32_t len;
char data[0];
} __attribute__((packed));
struct vusb_responses {
uint32_t len;
struct vusb_response* generic;
struct vusb_response* resps[0];
} __attribute__((packed));
static bool lookup_control_response(const struct vusb_descriptors* descs,
const struct vusb_responses* resps,
struct usb_ctrlrequest* ctrl,
char** response_data,
uint32_t* response_length) {
int descs_num = 0;
int resps_num = 0;
if (descs)
descs_num = (descs->len - offsetof(struct vusb_descriptors, descs)) /
sizeof(descs->descs[0]);
if (resps)
resps_num = (resps->len - offsetof(struct vusb_responses, resps)) /
sizeof(resps->resps[0]);
uint8_t req = ctrl->bRequest;
uint8_t req_type = ctrl->bRequestType & USB_TYPE_MASK;
uint8_t desc_type = ctrl->wValue >> 8;
if (req == USB_REQ_GET_DESCRIPTOR) {
int i;
for (i = 0; i < descs_num; i++) {
struct vusb_descriptor* desc = descs->descs[i];
if (!desc)
continue;
if (desc->req_type == req_type && desc->desc_type == desc_type) {
*response_length = desc->len;
if (*response_length != 0)
*response_data = &desc->data[0];
else
*response_data = NULL;
return true;
}
}
if (descs && descs->generic) {
*response_data = &descs->generic->data[0];
*response_length = descs->generic->len;
return true;
}
} else {
int i;
for (i = 0; i < resps_num; i++) {
struct vusb_response* resp = resps->resps[i];
if (!resp)
continue;
if (resp->type == req_type && resp->req == req) {
*response_length = resp->len;
if (*response_length != 0)
*response_data = &resp->data[0];
else
*response_data = NULL;
return true;
}
}
if (resps && resps->generic) {
*response_data = &resps->generic->data[0];
*response_length = resps->generic->len;
return true;
}
}
return false;
}
#define UDC_NAME_LENGTH_MAX 128
struct usb_raw_init {
__u8 driver_name[UDC_NAME_LENGTH_MAX];
__u8 device_name[UDC_NAME_LENGTH_MAX];
__u8 speed;
};
enum usb_raw_event_type {
USB_RAW_EVENT_INVALID = 0,
USB_RAW_EVENT_CONNECT = 1,
USB_RAW_EVENT_CONTROL = 2,
};
struct usb_raw_event {
__u32 type;
__u32 length;
__u8 data[0];
};
struct usb_raw_ep_io {
__u16 ep;
__u16 flags;
__u32 length;
__u8 data[0];
};
#define USB_RAW_EPS_NUM_MAX 30
#define USB_RAW_EP_NAME_MAX 16
#define USB_RAW_EP_ADDR_ANY 0xff
struct usb_raw_ep_caps {
__u32 type_control : 1;
__u32 type_iso : 1;
__u32 type_bulk : 1;
__u32 type_int : 1;
__u32 dir_in : 1;
__u32 dir_out : 1;
};
struct usb_raw_ep_limits {
__u16 maxpacket_limit;
__u16 max_streams;
__u32 reserved;
};
struct usb_raw_ep_info {
__u8 name[USB_RAW_EP_NAME_MAX];
__u32 addr;
struct usb_raw_ep_caps caps;
struct usb_raw_ep_limits limits;
};
struct usb_raw_eps_info {
struct usb_raw_ep_info eps[USB_RAW_EPS_NUM_MAX];
};
#define USB_RAW_IOCTL_INIT _IOW('U', 0, struct usb_raw_init)
#define USB_RAW_IOCTL_RUN _IO('U', 1)
#define USB_RAW_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_raw_event)
#define USB_RAW_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP0_READ _IOWR('U', 4, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor)
#define USB_RAW_IOCTL_EP_DISABLE _IOW('U', 6, __u32)
#define USB_RAW_IOCTL_EP_WRITE _IOW('U', 7, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP_READ _IOWR('U', 8, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_CONFIGURE _IO('U', 9)
#define USB_RAW_IOCTL_VBUS_DRAW _IOW('U', 10, __u32)
#define USB_RAW_IOCTL_EPS_INFO _IOR('U', 11, struct usb_raw_eps_info)
#define USB_RAW_IOCTL_EP0_STALL _IO('U', 12)
#define USB_RAW_IOCTL_EP_SET_HALT _IOW('U', 13, __u32)
#define USB_RAW_IOCTL_EP_CLEAR_HALT _IOW('U', 14, __u32)
#define USB_RAW_IOCTL_EP_SET_WEDGE _IOW('U', 15, __u32)
static int usb_raw_open() {
return open("/dev/raw-gadget", O_RDWR);
}
static int usb_raw_init(int fd,
uint32_t speed,
const char* driver,
const char* device) {
struct usb_raw_init arg;
strncpy((char*)&arg.driver_name[0], driver, sizeof(arg.driver_name));
strncpy((char*)&arg.device_name[0], device, sizeof(arg.device_name));
arg.speed = speed;
return ioctl(fd, USB_RAW_IOCTL_INIT, &arg);
}
static int usb_raw_run(int fd) {
return ioctl(fd, USB_RAW_IOCTL_RUN, 0);
}
static int usb_raw_configure(int fd) {
return ioctl(fd, USB_RAW_IOCTL_CONFIGURE, 0);
}
static int usb_raw_vbus_draw(int fd, uint32_t power) {
return ioctl(fd, USB_RAW_IOCTL_VBUS_DRAW, power);
}
static int usb_raw_ep0_write(int fd, struct usb_raw_ep_io* io) {
return ioctl(fd, USB_RAW_IOCTL_EP0_WRITE, io);
}
static int usb_raw_ep0_read(int fd, struct usb_raw_ep_io* io) {
return ioctl(fd, USB_RAW_IOCTL_EP0_READ, io);
}
static int usb_raw_event_fetch(int fd, struct usb_raw_event* event) {
return ioctl(fd, USB_RAW_IOCTL_EVENT_FETCH, event);
}
static int usb_raw_ep_enable(int fd, struct usb_endpoint_descriptor* desc) {
return ioctl(fd, USB_RAW_IOCTL_EP_ENABLE, desc);
}
static int usb_raw_ep_disable(int fd, int ep) {
return ioctl(fd, USB_RAW_IOCTL_EP_DISABLE, ep);
}
static int usb_raw_ep0_stall(int fd) {
return ioctl(fd, USB_RAW_IOCTL_EP0_STALL, 0);
}
static int lookup_interface(int fd,
uint8_t bInterfaceNumber,
uint8_t bAlternateSetting) {
struct usb_device_index* index = lookup_usb_index(fd);
if (!index)
return -1;
for (int i = 0; i < index->ifaces_num; i++) {
if (index->ifaces[i].bInterfaceNumber == bInterfaceNumber &&
index->ifaces[i].bAlternateSetting == bAlternateSetting)
return i;
}
return -1;
}
#define USB_MAX_PACKET_SIZE 4096
struct usb_raw_control_event {
struct usb_raw_event inner;
struct usb_ctrlrequest ctrl;
char data[USB_MAX_PACKET_SIZE];
};
struct usb_raw_ep_io_data {
struct usb_raw_ep_io inner;
char data[USB_MAX_PACKET_SIZE];
};
static void set_interface(int fd, int n) {
struct usb_device_index* index = lookup_usb_index(fd);
if (!index)
return;
if (index->iface_cur >= 0 && index->iface_cur < index->ifaces_num) {
for (int ep = 0; ep < index->ifaces[index->iface_cur].eps_num; ep++) {
int rv = usb_raw_ep_disable(
fd, index->ifaces[index->iface_cur].eps[ep].handle);
if (rv < 0) {
} else {
}
}
}
if (n >= 0 && n < index->ifaces_num) {
for (int ep = 0; ep < index->ifaces[n].eps_num; ep++) {
int rv = usb_raw_ep_enable(fd, &index->ifaces[n].eps[ep].desc);
if (rv < 0) {
} else {
index->ifaces[n].eps[ep].handle = rv;
}
}
index->iface_cur = n;
}
}
static int configure_device(int fd) {
struct usb_device_index* index = lookup_usb_index(fd);
if (!index)
return -1;
int rv = usb_raw_vbus_draw(fd, index->bMaxPower);
if (rv < 0) {
return rv;
}
rv = usb_raw_configure(fd);
if (rv < 0) {
return rv;
}
set_interface(fd, 0);
return 0;
}
static volatile long syz_usb_connect_impl(
uint64_t speed,
uint64_t dev_len,
const char* dev,
const struct vusb_connect_descriptors* descs,
lookup_connect_out_response_t lookup_connect_response_out) {
if (!dev) {
return -1;
}
int fd = usb_raw_open();
if (fd < 0) {
return fd;
}
if (fd >= MAX_FDS) {
close(fd);
return -1;
}
struct usb_device_index* index = add_usb_index(fd, dev, dev_len);
if (!index) {
return -1;
}
char device[32];
sprintf(&device[0], "dummy_udc.%llu", procid);
int rv = usb_raw_init(fd, speed, "dummy_udc", &device[0]);
if (rv < 0) {
return rv;
}
rv = usb_raw_run(fd);
if (rv < 0) {
return rv;
}
bool done = false;
while (!done) {
struct usb_raw_control_event event;
event.inner.type = 0;
event.inner.length = sizeof(event.ctrl);
rv = usb_raw_event_fetch(fd, (struct usb_raw_event*)&event);
if (rv < 0) {
return rv;
}
if (event.inner.type != USB_RAW_EVENT_CONTROL)
continue;
char* response_data = NULL;
uint32_t response_length = 0;
struct usb_qualifier_descriptor qual;
if (event.ctrl.bRequestType & USB_DIR_IN) {
if (!lookup_connect_response_in(fd, descs, &event.ctrl, &qual,
&response_data, &response_length)) {
usb_raw_ep0_stall(fd);
continue;
}
} else {
if (!lookup_connect_response_out(fd, descs, &event.ctrl, &done)) {
usb_raw_ep0_stall(fd);
continue;
}
response_data = NULL;
response_length = event.ctrl.wLength;
}
if ((event.ctrl.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
event.ctrl.bRequest == USB_REQ_SET_CONFIGURATION) {
rv = configure_device(fd);
if (rv < 0) {
return rv;
}
}
struct usb_raw_ep_io_data response;
response.inner.ep = 0;
response.inner.flags = 0;
if (response_length > sizeof(response.data))
response_length = 0;
if (event.ctrl.wLength < response_length)
response_length = event.ctrl.wLength;
response.inner.length = response_length;
if (response_data)
memcpy(&response.data[0], response_data, response_length);
else
memset(&response.data[0], 0, response_length);
if (event.ctrl.bRequestType & USB_DIR_IN) {
rv = usb_raw_ep0_write(fd, (struct usb_raw_ep_io*)&response);
} else {
rv = usb_raw_ep0_read(fd, (struct usb_raw_ep_io*)&response);
}
if (rv < 0) {
return rv;
}
}
sleep_ms(200);
return fd;
}
static volatile long syz_usb_connect(volatile long a0,
volatile long a1,
volatile long a2,
volatile long a3) {
uint64_t speed = a0;
uint64_t dev_len = a1;
const char* dev = (const char*)a2;
const struct vusb_connect_descriptors* descs =
(const struct vusb_connect_descriptors*)a3;
return syz_usb_connect_impl(speed, dev_len, dev, descs,
&lookup_connect_response_out_generic);
}
static volatile long syz_usb_control_io(volatile long a0,
volatile long a1,
volatile long a2) {
int fd = a0;
const struct vusb_descriptors* descs = (const struct vusb_descriptors*)a1;
const struct vusb_responses* resps = (const struct vusb_responses*)a2;
struct usb_raw_control_event event;
event.inner.type = 0;
event.inner.length = USB_MAX_PACKET_SIZE;
int rv = usb_raw_event_fetch(fd, (struct usb_raw_event*)&event);
if (rv < 0) {
return rv;
}
if (event.inner.type != USB_RAW_EVENT_CONTROL) {
return -1;
}
char* response_data = NULL;
uint32_t response_length = 0;
if ((event.ctrl.bRequestType & USB_DIR_IN) && event.ctrl.wLength) {
if (!lookup_control_response(descs, resps, &event.ctrl, &response_data,
&response_length)) {
usb_raw_ep0_stall(fd);
return -1;
}
} else {
if ((event.ctrl.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD ||
event.ctrl.bRequest == USB_REQ_SET_INTERFACE) {
int iface_num = event.ctrl.wIndex;
int alt_set = event.ctrl.wValue;
int iface_index = lookup_interface(fd, iface_num, alt_set);
if (iface_index < 0) {
} else {
set_interface(fd, iface_index);
}
}
response_length = event.ctrl.wLength;
}
struct usb_raw_ep_io_data response;
response.inner.ep = 0;
response.inner.flags = 0;
if (response_length > sizeof(response.data))
response_length = 0;
if (event.ctrl.wLength < response_length)
response_length = event.ctrl.wLength;
if ((event.ctrl.bRequestType & USB_DIR_IN) && !event.ctrl.wLength) {
response_length = USB_MAX_PACKET_SIZE;
}
response.inner.length = response_length;
if (response_data)
memcpy(&response.data[0], response_data, response_length);
else
memset(&response.data[0], 0, response_length);
if ((event.ctrl.bRequestType & USB_DIR_IN) && event.ctrl.wLength) {
rv = usb_raw_ep0_write(fd, (struct usb_raw_ep_io*)&response);
} else {
rv = usb_raw_ep0_read(fd, (struct usb_raw_ep_io*)&response);
}
if (rv < 0) {
return rv;
}
sleep_ms(200);
return 0;
}
uint64_t r[1] = {0xffffffffffffffff};
int main(void) {
syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
intptr_t res = 0;
memcpy((void*)0x20000000,
"\x12\x01\x00\x00\xbc\x61\xb4\x08\xb4\x07\x0a\x01\x02\x01\x00\x00\x00"
"\x01\x09\x02\x24\x00\x01\x00\x00\x00\x5b\x09\x04\x00\x00\x02\x19\xa4"
"\xb4\x00\x09\x05\x0e\x02\x00\x1b\xc4\x00\x00\x09\x05\x82\x02",
49);
res = -1;
res = syz_usb_connect(/*speed=*/0, /*dev_len=*/0x36, /*dev=*/0x20000000,
/*conn_descs=*/0);
if (res != -1)
r[0] = res;
*(uint32_t*)0x20000840 = 0x84;
*(uint64_t*)0x20000844 = 0x20000440;
*(uint8_t*)0x20000440 = 0x20;
*(uint8_t*)0x20000441 = 7;
*(uint32_t*)0x20000442 = 0xba;
memcpy((void*)0x20000446,
"\x26\x15\x91\x55\x33\xe9\x67\xd6\x3c\x01\xba\x52\xb0\x88\xd8\x2d\x33"
"\x31\x9a\x3e\xe5\x79\x49\x03\xde\xd3\xff\x0b\xae\xa8\xb5\xdc\x7b\xbf"
"\x28\x50\x84\x2d\x6c\xcd\xcd\x31\xf7\xfb\xbd\x78\xf4\xac\x80\x16\xc7"
"\xfc\xb6\xb4\xca\x77\x5e\x60\x83\xd1\x1b\x74\x14\x44\x19\xdd\x07\xf6"
"\x9a\x2e\x65\xa5\x57\x1a\xd0\x33\x15\x63\x7a\x0a\x29\x31\x75\x3c\x25"
"\x7f\x8c\x22\x0f\xdb\x24\xdd\x1c\xb8\x66\xaa\xfc\xac\x61\xe7\x84\x10"
"\x33\x27\x12\xaa\x5c\x6a\x21\xbe\xdd\x0b\x2f\x06\x29\xdc\x6c\xe2\x8c"
"\x9a\x1b\xfd\xdf\x71\x15\x31\x5d\x4c\x5a\x1c\x29\x73\x01\x69\x9e\x67"
"\xc3\x27\xa7\x55\xd5\x4a\xe7\xdd\x85\xcc\x1b\xfb\xdf\xba\xa7\x1f\xad"
"\x59\xdb\xde\x04\xc2\xe6\x6a\x52\x9b\x9b\x2d\x47\x59\xf8\x44\xd5\xdd"
"\x37\x52\x31\x4f\x35\xe2\x65\x5b\x78\x6a\x1d\xcd\x9c\xa0\x38\xe8",
186);
*(uint64_t*)0x2000084c = 0;
*(uint64_t*)0x20000854 = 0;
*(uint64_t*)0x2000085c = 0;
*(uint64_t*)0x20000864 = 0;
*(uint64_t*)0x2000086c = 0;
*(uint64_t*)0x20000874 = 0;
*(uint64_t*)0x2000087c = 0;
*(uint64_t*)0x20000884 = 0;
*(uint64_t*)0x2000088c = 0;
*(uint64_t*)0x20000894 = 0;
*(uint64_t*)0x2000089c = 0;
*(uint64_t*)0x200008a4 = 0;
*(uint64_t*)0x200008ac = 0;
*(uint64_t*)0x200008b4 = 0;
*(uint64_t*)0x200008bc = 0;
syz_usb_control_io(/*fd=*/r[0], /*descs=*/0, /*resps=*/0x20000840);
{
int i;
for (i = 0; i < 64; i++) {
syz_usb_control_io(/*fd=*/r[0], /*descs=*/0, /*resps=*/0x20000840);
}
}
return 0;
}
=* repro.txt =*
r0 = syz_usb_connect(0x0, 0x36,
&(0x7f0000000000)=ANY=[@ANYBLOB="12010000bc61b408b4070a0102010000000109022400010000005b090400000219a4b40009050e02001bc4000009058202"],
0x0)
syz_usb_control_io(r0, 0x0, &(0x7f0000000840)={0x84,
&(0x7f0000000440)={0x20, 0x7, 0xba,
"2615915533e967d63c01ba52b088d82d33319a3ee5794903ded3ff0baea8b5dc7bbf2850842d6ccdcd31f7fbbd78f4ac8016c7fcb6b4ca775e6083d11b74144419dd07f69a2e65a5571ad03315637a0a2931753c257f8c220fdb24dd1cb866aafcac61e78410332712aa5c6a21bedd0b2f0629dc6ce28c9a1bfddf7115315d4c5a1c297301699e67c327a755d54ae7dd85cc1bfbdfbaa71fad59dbde04c2e66a529b9b2d4759f844d5dd3752314f35e2655b786a1dcd9ca038e8"},
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0}) (rerun: 64)
See aslo https://gist.github.com/xrivendell7/e2dd691a52c379bbbc3db81fb3f8e0fc.
I hope it helps.
Best regards.
xingwei Lee
On Sun, Mar 17, 2024 at 04:31:01PM +0800, xingwei lee wrote:
> Hello I found a bug in latest upstream titled "divide error in
> alauda_transport", and maybe is realted with usb.
> I comfired in the latest upstream the poc tree can trigger the issue.
>
> If you fix this issue, please add the following tag to the commit:
> Reported-by: xingwei lee <[email protected]>
> Reported-by: yue sun <[email protected]>
>
> kernel: upstream 9187210eee7d87eea37b45ea93454a88681894a4
> config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=1c6662240382da2
> with KASAN enabled
> compiler: gcc (Debian 12.2.0-14) 12.2.0
>
> divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
> CPU: 2 PID: 8229 Comm: usb-storage Not tainted 6.8.0-05202-g9187210eee7d #20
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.16.2-1.fc38 04/01/2014
> RIP: 0010:alauda_read_data drivers/usb/storage/alauda.c:954 [inline]
> RIP: 0010:alauda_transport+0xcaf/0x3830 drivers/usb/storage/alauda.c:1184
Can you please test the patch below?
Alan Stern
Index: usb-devel/drivers/usb/storage/alauda.c
===================================================================
--- usb-devel.orig/drivers/usb/storage/alauda.c
+++ usb-devel/drivers/usb/storage/alauda.c
@@ -951,7 +951,6 @@ static int alauda_read_data(struct us_da
unsigned int lba_offset = lba - (zone * uzonesize);
unsigned int pages;
u16 pba;
- alauda_ensure_map_for_zone(us, zone);
/* Not overflowing capacity? */
if (lba >= max_lba) {
@@ -961,6 +960,8 @@ static int alauda_read_data(struct us_da
break;
}
+ alauda_ensure_map_for_zone(us, zone);
+
/* Find number of pages we can read in this block */
pages = min(sectors, blocksize - page);
len = pages << pageshift;
On Mar 17, 2024, at 23:04, Alan Stern <[email protected]> wrote:
On Sun, Mar 17, 2024 at 04:31:01PM +0800, xingwei lee wrote:
Hello I found a bug in latest upstream titled "divide error in
alauda_transport", and maybe is realted with usb.
I comfired in the latest upstream the poc tree can trigger the issue.
If you fix this issue, please add the following tag to the commit:
Reported-by: xingwei lee <[email protected]>
Reported-by: yue sun <[email protected]>
kernel: upstream 9187210eee7d87eea37b45ea93454a88681894a4
config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=1c6662240382da2
with KASAN enabled
compiler: gcc (Debian 12.2.0-14) 12.2.0
divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 2 PID: 8229 Comm: usb-storage Not tainted 6.8.0-05202-g9187210eee7d #20
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.2-1.fc38 04/01/2014
RIP: 0010:alauda_read_data drivers/usb/storage/alauda.c:954 [inline]
RIP: 0010:alauda_transport+0xcaf/0x3830 drivers/usb/storage/alauda.c:1184
Can you please test the patch below?
Alan Stern
Index: usb-devel/drivers/usb/storage/alauda.c
===================================================================
--- usb-devel.orig/drivers/usb/storage/alauda.c
+++ usb-devel/drivers/usb/storage/alauda.c
@@ -951,7 +951,6 @@ static int alauda_read_data(struct us_da
unsigned int lba_offset = lba - (zone * uzonesize);
unsigned int pages;
u16 pba;
- alauda_ensure_map_for_zone(us, zone);
/* Not overflowing capacity? */
if (lba >= max_lba) {
@@ -961,6 +960,8 @@ static int alauda_read_data(struct us_da
break;
}
+ alauda_ensure_map_for_zone(us, zone);
+
/* Find number of pages we can read in this block */
pages = min(sectors, blocksize - page);
len = pages << pageshift;
Hi Alan
I apply your patch in my upstream commit
9187210eee7d87eea37b45ea93454a88681894a4
diff --git a/drivers/usb/storage/alauda.c b/drivers/usb/storage/alauda.c
index 115f05a6201a..6eccbadcea78 100644
--- a/drivers/usb/storage/alauda.c
+++ b/drivers/usb/storage/alauda.c
@@ -951,7 +951,6 @@ static int alauda_read_data(struct us_data *us,
unsigned long address,
unsigned int lba_offset = lba - (zone * uzonesize);
unsigned int pages;
u16 pba;
- alauda_ensure_map_for_zone(us, zone);
/* Not overflowing capacity? */
if (lba >= max_lba) {
@@ -961,6 +960,8 @@ static int alauda_read_data(struct us_data *us,
unsigned long address,
break;
}
+ alauda_ensure_map_for_zone(us, zone);
+
/* Find number of pages we can read in this block */
pages = min(sectors, blocksize - page);
len = pages << pageshift;
However, the poc still trigger the bug like below:
root@syzkaller:~# ./55a
[ 143.702248][ T29] usb 1-1: new high-speed USB device number 2
using dummy_hcd
[ 143.941971][ T29] usb 1-1: Using ep0 maxpacket: 8
[ 144.062985][ T29] usb 1-1: config 0 interface 0 altsetting 0
endpoint 0xE has invalid maxpacket 6912, setting to 1024
[ 144.066725][ T29] usb 1-1: config 0 interface 0 altsetting 0 bulk
endpoint 0xE has invalid maxpacket 1024
[ 144.069851][ T29] usb 1-1: config 0 interface 0 altsetting 0
endpoint 0x82 has invalid wMaxPacketSize 0
[ 144.073033][ T29] usb 1-1: config 0 interface 0 altsetting 0 bulk
endpoint 0x82 has invalid maxpacket 0
[ 144.076132][ T29] usb 1-1: New USB device found, idVendor=07b4,
idProduct=010a, bcdDevice= 1.02
[ 144.079142][ T29] usb 1-1: New USB device strings: Mfr=0,
Product=0, SerialNumber=0
[ 144.082673][ T4526] systemd-journald[4526]: sd-device: Failed to
chase symlinks in "/sys/dev/char/189:1".
[ 144.086529][ T29] usb 1-1: config 0 descriptor??
[ 144.103215][ T8204] raw-gadget.0 gadget.0: fail, usb_ep_enable returned -22
[ 144.124706][ T29] ums-alauda 1-1:0.0: USB Mass Storage device detected
[ 144.153028][ T29] scsi host2: usb-storage 1-1:0.0
[ 145.216626][ T1020] scsi 2:0:0:0: Direct-Access Olympus
MAUSB-10 (Alauda 0102 PQ: 0 ANSI: 0 CCS
[ 145.219706][ T1020] scsi 2:0:0:1: Direct-Access Olympus
MAUSB-10 (Alauda 0102 PQ: 0 ANSI: 0 CCS
[ 145.234829][ T1020] sd 2:0:0:0: Attached scsi generic sg2 type 0
[ 145.251393][ T1020] sd 2:0:0:1: Attached scsi generic sg3 type 0
[ 145.492274][ T73] sd 2:0:0:0: [sdb] Very big device. Trying to
use READ CAPACITY(16).
[ 145.932043][ T12] sd 2:0:0:1: [sdc] Very big device. Trying to
use READ CAPACITY(16).
[ 145.932844][ T73] sd 2:0:0:0: [sdb] Using 0xffffffff as device size
[ 145.935914][ T12] sd 2:0:0:1: [sdc] Using 0xffffffff as device size
[ 146.141945][ T8215] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
[ 146.143565][ T8215] CPU: 1 PID: 8215 Comm: usb-storage Not tainted
6.8.0-05202-g9187210eee7d-dirty #21
[ 146.145319][ T8215] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS 1.16.2-1.fc38 04/01/2014
[ 146.146720][ T8215] RIP: 0010:alauda_transport+0xc65/0x38b0
[ 146.147977][ T8215] Code: 84 24 08 01 00 00 00 00 00 00 48 c7 84 24
18 01 00 00 00 00 00 00 48 d3 eb 48 89 d9 85 f6 0f 84 5b 12 00 00 31
d2 41 0f b7 c4 <f7> 74 24 40 66 41 39 dc 41 89 c6 0f 83 08 02 00 00 41
81
[ 146.150664][ T8215] RSP: 0018:ffffc9001005fa60 EFLAGS: 00010246
[ 146.151539][ T8215] RAX: 0000000000000000 RBX: 0000000000000000
RCX: 0000000000000000
[ 146.152672][ T8215] RDX: 0000000000000000 RSI: 0000000000000001
RDI: ffff88802d3d5a00
[ 146.153819][ T8215] RBP: 1ffff9200200bf69 R08: 0000000000000001
R09: ffffed1005ed15ad
[ 146.154982][ T8215] R10: ffff88802f68b088 R11: ffff88802f68acb8
R12: 0000000000000000
[ 146.156122][ T8215] R13: 0000000000000000 R14: 0000000000000000
R15: ffff88802d3d5a00
[ 146.157275][ T8215] FS: 0000000000000000(0000)
GS:ffff88823bc00000(0000) knlGS:0000000000000000
[ 146.158578][ T8215] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 146.159536][ T8215] CR2: 000055e7fa9c4770 CR3: 000000000c774000
CR4: 0000000000750ef0
[ 146.160699][ T8215] PKRU: 55555554
[ 146.161232][ T8215] Call Trace:
[ 146.161730][ T8215] <TASK>
[ 146.162173][ T8215] ? die+0x31/0x80
[ 146.162718][ T8215] ? do_trap+0x1b4/0x3c0
[ 146.163355][ T8215] ? alauda_transport+0xc65/0x38b0
[ 146.164115][ T8215] ? do_error_trap+0x9e/0x160
[ 146.164788][ T8215] ? alauda_transport+0xc65/0x38b0
[ 146.165542][ T8215] ? exc_divide_error+0x38/0x50
[ 146.166259][ T8215] ? alauda_transport+0xc65/0x38b0
[ 146.167008][ T8215] ? asm_exc_divide_error+0x1a/0x20
[ 146.167782][ T8215] ? alauda_transport+0xc65/0x38b0
[ 146.168546][ T8215] ? __pfx___lock_acquire+0x10/0x10
[ 146.169309][ T8215] ? __pfx_alauda_transport+0x10/0x10
[ 146.170098][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.170909][ T8215] ? __lock_acquire+0x193f/0x5c00
[ 146.171639][ T8215] usb_stor_invoke_transport+0xea/0x13d0
[ 146.172465][ T8215] ? __pfx_mark_lock+0x10/0x10
[ 146.173179][ T8215] ? __mutex_lock+0x25a/0x1330
[ 146.173893][ T8215] ? __pfx_usb_stor_invoke_transport+0x10/0x10
[ 146.174796][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.175640][ T8215] ? find_held_lock+0x2d/0x110
[ 146.176357][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.177172][ T8215] ? usb_stor_control_thread+0x304/0x980
[ 146.178002][ T8215] ? __pfx_lock_release+0x10/0x10
[ 146.178745][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.179581][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.180406][ T8215] ? mark_held_locks+0x9f/0xe0
[ 146.181114][ T8215] usb_stor_control_thread+0x5d6/0x980
[ 146.181928][ T8215] ? __pfx_usb_stor_control_thread+0x10/0x10
[ 146.182784][ T8215] ? _raw_spin_unlock_irqrestore+0x52/0x80
[ 146.183620][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.184438][ T8215] ? lockdep_hardirqs_on+0x7c/0x100
[ 146.185196][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.186007][ T8215] ? srso_alias_return_thunk+0x5/0xfbef5
[ 146.186808][ T8215] ? __kthread_parkme+0xb5/0x1f0
[ 146.187545][ T8215] ? __pfx_usb_stor_control_thread+0x10/0x10
[ 146.188418][ T8215] kthread+0x2eb/0x3d0
[ 146.189202][ T8215] ? _raw_spin_unlock_irq+0x23/0x50
[ 146.189981][ T8215] ? __pfx_kthread+0x10/0x10
[ 146.190712][ T8215] ret_from_fork+0x2f/0x70
[ 146.191387][ T8215] ? __pfx_kthread+0x10/0x10
[ 146.192065][ T8215] ret_from_fork_asm+0x1a/0x30
[ 146.192765][ T8215] </TASK>
[ 146.193222][ T8215] Modules linked in:
[ 146.193986][ T8215] ---[ end trace 0000000000000000 ]---
[ 146.194815][ T8215] RIP: 0010:alauda_transport+0xc65/0x38b0
[ 146.195724][ T8215] Code: 84 24 08 01 00 00 00 00 00 00 48 c7 84 24
18 01 00 00 00 00 00 00 48 d3 eb 48 89 d9 85 f6 0f 84 5b 12 00 00 31
d2 41 0f b7 c4 <f7> 74 24 40 66 41 39 dc 41 89 c6 0f 83 08 02 00 00 41
81
[ 146.198822][ T8215] RSP: 0018:ffffc9001005fa60 EFLAGS: 00010246
[ 146.199783][ T8215] RAX: 0000000000000000 RBX: 0000000000000000
RCX: 0000000000000000
[ 146.200998][ T8215] RDX: 0000000000000000 RSI: 0000000000000001
RDI: ffff88802d3d5a00
[ 146.202239][ T8215] RBP: 1ffff9200200bf69 R08: 0000000000000001
R09: ffffed1005ed15ad
[ 146.203581][ T8215] R10: ffff88802f68b088 R11: ffff88802f68acb8
R12: 0000000000000000
[ 146.204813][ T8215] R13: 0000000000000000 R14: 0000000000000000
R15: ffff88802d3d5a00
[ 146.206034][ T8215] FS: 0000000000000000(0000)
GS:ffff88823bd00000(0000) knlGS:0000000000000000
[ 146.207351][ T8215] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 146.208325][ T8215] CR2: 000055e7fa9cf2c8 CR3: 0000000027014000
CR4: 0000000000750ef0
[ 146.209490][ T8215] PKRU: 55555554
[ 146.210032][ T8215] Kernel panic - not syncing: Fatal exception
[ 146.211335][ T8215] Kernel Offset: disabled
[ 146.212003][ T8215] Rebooting in 86400 seconds..
Best regards
xingwei Lee
On Sun, Mar 17, 2024 at 11:57:58PM +0800, xingwei lee wrote:
> On Mar 17, 2024, at 23:04, Alan Stern <[email protected]> wrote:
>
> On Sun, Mar 17, 2024 at 04:31:01PM +0800, xingwei lee wrote:
>
> Hello I found a bug in latest upstream titled "divide error in
> alauda_transport", and maybe is realted with usb.
> I comfired in the latest upstream the poc tree can trigger the issue.
>
> If you fix this issue, please add the following tag to the commit:
> Reported-by: xingwei lee <[email protected]>
> Reported-by: yue sun <[email protected]>
>
> kernel: upstream 9187210eee7d87eea37b45ea93454a88681894a4
> config: https://syzkaller.appspot.com/text?tag=KernelConfig&x=1c6662240382da2
> with KASAN enabled
> compiler: gcc (Debian 12.2.0-14) 12.2.0
>
> divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
> CPU: 2 PID: 8229 Comm: usb-storage Not tainted 6.8.0-05202-g9187210eee7d #20
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.16.2-1.fc38 04/01/2014
> RIP: 0010:alauda_read_data drivers/usb/storage/alauda.c:954 [inline]
> RIP: 0010:alauda_transport+0xcaf/0x3830 drivers/usb/storage/alauda.c:1184
> Hi Alan
>
> I apply your patch in my upstream commit
> 9187210eee7d87eea37b45ea93454a88681894a4
> However, the poc still trigger the bug like below:
> [ 146.141945][ T8215] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI
> [ 146.143565][ T8215] CPU: 1 PID: 8215 Comm: usb-storage Not tainted
> 6.8.0-05202-g9187210eee7d-dirty #21
> [ 146.145319][ T8215] Hardware name: QEMU Standard PC (i440FX + PIIX,
> 1996), BIOS 1.16.2-1.fc38 04/01/2014
> [ 146.146720][ T8215] RIP: 0010:alauda_transport+0xc65/0x38b0
The line in your original bug report, alauda.c:954, was a call to
alauda_ensure_map_for_zone(), which my patch moves to a different
location so that a test for overflow can run first. It's hard to tell
whether the divide error occurs before the function call, within the
function, or after.
Furthermore, alauda_ensure_map_for_zone() calls alauda_read_map(), and
it's hard to tell if the divide error occurs before that function call
or within the function.
Can you try adding some pr_info() statements to those places so we can
determine exactly where the error occurs? The only divisions that I see
are by 2 or by uzonesize, which should always be nonzero. Maybe you can
print out the value of uzonesize so we can verify this.
Thanks,
Alan Stern