3rd-party/linux-kernel-module-cheat
1
0
Fork 0
mirror of https://github.com/cirosantilli/linux-kernel-module-cheat.git synced 2026-01-23 02:05:57 +01:00
Code Issues Releases Wiki Activity

Spaces to tabs

Browse Source
This commit is contained in:
Ciro Santilli
2017-06-08 06:26:20 +01:00
parent 41dbf46531
commit 4c1b0e7891
7 changed files with 85 additions and 85 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
kernel_module/debugfs.c
View File

@@ -19,23 +19,23 @@ static u32 value = 42;
static int myinit(void)
{
struct dentry *file;
dir = debugfs_create_dir("lkmc_debugfs", 0);
if (!dir) {
printk(KERN_ALERT "debugfs_create_dir failed");
return -1;
}
file = debugfs_create_u32("myfile", 0666, dir, &value);
if (!file) {
printk(KERN_ALERT "debugfs_create_u32 failed");
return -1;
}
return 0;
struct dentry *file;
dir = debugfs_create_dir("lkmc_debugfs", 0);
if (!dir) {
printk(KERN_ALERT "debugfs_create_dir failed");
return -1;
}
file = debugfs_create_u32("myfile", 0666, dir, &value);
if (!file) {
printk(KERN_ALERT "debugfs_create_u32 failed");
return -1;
}
return 0;
}
static void myexit(void)
{
debugfs_remove_recursive(dir);
debugfs_remove_recursive(dir);
}
module_init(myinit)

52
kernel_module/dep.c
View File

@@ -1,38 +1,38 @@
/*
Exports the lkmc_dep which dep2.ko uses.
insmod /dep.ko
# dmesg => 0
# dmesg => 0
# dmesg => ...
insmod /dep2.ko
# dmesg => 1
# dmesg => 2
# dmesg => ...
rmmod dep
# Fails because dep2 uses it.
rmmod dep2
# Dmesg stops incrementing.
rmmod dep
insmod /dep.ko
# dmesg => 0
# dmesg => 0
# dmesg => ...
insmod /dep2.ko
# dmesg => 1
# dmesg => 2
# dmesg => ...
rmmod dep
# Fails because dep2 uses it.
rmmod dep2
# Dmesg stops incrementing.
rmmod dep
sys visibility:
dmesg -n 1
insmod /dep.ko
insmod /dep2.ko
ls -l /sys/module/dep/holders
# => ../../dep2
cat refcnt
# => 1
dmesg -n 1
insmod /dep.ko
insmod /dep2.ko
ls -l /sys/module/dep/holders
# => ../../dep2
cat refcnt
# => 1
depmod:
grep dep "/lib/module/"*"/depmod"
# extra/dep2.ko: extra/dep.ko
# extra/dep.ko:
modprobe dep
# lsmod
# Both dep and dep2 were loaded.
grep dep "/lib/module/"*"/depmod"
# extra/dep2.ko: extra/dep.ko
# extra/dep.ko:
modprobe dep
# lsmod
# Both dep and dep2 were loaded.
TODO: at what point does buildroot / busybox generate that file?
*/

2
kernel_module/fops.c
View File

@@ -144,7 +144,7 @@ static int myinit(void)
printk(KERN_ALERT "debugfs_create_dir failed");
return -1;
}
file = debugfs_create_file("f", 0666, dir, NULL, &fops);
file = debugfs_create_file("f", 0666, dir, NULL, &fops);
if (!file) {
printk(KERN_ALERT "debugfs_create_file failed");
return -1;

4
kernel_module/irq.c
View File

@@ -13,8 +13,8 @@ MODULE_LICENSE("GPL");
* Return value from kernel docs:*
*
* enum irqreturn
* @IRQ_NON interrupt was not from this device or was not handled
* @IRQ_HANDLED interrupt was handled by this device
* @IRQ_NON interrupt was not from this device or was not handled
* @IRQ_HANDLED interrupt was handled by this device
* @IRQ_WAKE_THREAD handler requests to wake the handler thread
*/
static irqreturn_t handler(int i, void *v)

28
kernel_module/test/myinsmod.c
View File

@@ -12,23 +12,23 @@
int main(int argc, char **argv) {
size_t image_size;
void *image;
int fd;
struct stat st;
int fd;
struct stat st;
if (argc != 2) {
puts("Usage ./prog mymodule.ko");
return EXIT_FAILURE;
}
fd = open(argv[1], O_RDONLY);
fstat(fd, &st);
image_size = st.st_size;
image = malloc(image_size);
read(fd, image, image_size);
close(fd);
if (init_module(image, image_size, "") != 0) {
perror("init_module");
return EXIT_FAILURE;
}
free(image);
return EXIT_SUCCESS;
fd = open(argv[1], O_RDONLY);
fstat(fd, &st);
image_size = st.st_size;
image = malloc(image_size);
read(fd, image, image_size);
close(fd);
if (init_module(image, image_size, "") != 0) {
perror("init_module");
return EXIT_FAILURE;
}
free(image);
return EXIT_SUCCESS;
}

10
kernel_module/test/myrmmod.c
View File

@@ -14,9 +14,9 @@ int main(int argc, char **argv) {
puts("Usage ./prog mymodule");
return EXIT_FAILURE;
}
if (delete_module(argv[1], O_NONBLOCK) != 0) {
perror("delete_module");
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
if (delete_module(argv[1], O_NONBLOCK) != 0) {
perror("delete_module");
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}

48
kernel_module/test/poll.c
View File

@@ -6,29 +6,29 @@
#include <unistd.h> /* read */
int main(int argc, char **argv) {
char buf[1024], path[1024];
int fd, i, n;
short revents;
struct pollfd pfd;
char buf[1024], path[1024];
int fd, i, n;
short revents;
struct pollfd pfd;
fd = open(argv[1], O_RDONLY | O_NONBLOCK);
if (fd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
pfd.fd = fd;
pfd.events = POLLIN;
while (1) {
puts("loop");
i = poll(&pfd, 1, -1);
if (i == -1) {
perror("poll");
exit(EXIT_FAILURE);
}
revents = pfd.revents;
if (revents & POLLIN) {
n = read(pfd.fd, buf, sizeof(buf));
printf("POLLIN n=%d buf=%.*s\n", n, n, buf);
}
}
fd = open(argv[1], O_RDONLY | O_NONBLOCK);
if (fd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
pfd.fd = fd;
pfd.events = POLLIN;
while (1) {
puts("loop");
i = poll(&pfd, 1, -1);
if (i == -1) {
perror("poll");
exit(EXIT_FAILURE);
}
revents = pfd.revents;
if (revents & POLLIN) {
n = read(pfd.fd, buf, sizeof(buf));
printf("POLLIN n=%d buf=%.*s\n", n, n, buf);
}
}
}