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-rw-r--r--kernel/module/decompress.c2
-rw-r--r--kernel/module/kallsyms.c28
-rw-r--r--kernel/module/main.c124
-rw-r--r--kernel/module/stats.c4
4 files changed, 103 insertions, 55 deletions
diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c
index e97232b125eb..8a5d6d63b06c 100644
--- a/kernel/module/decompress.c
+++ b/kernel/module/decompress.c
@@ -257,7 +257,7 @@ static ssize_t module_zstd_decompress(struct load_info *info,
do {
struct page *page = module_get_next_page(info);
- if (!IS_ERR(page)) {
+ if (IS_ERR(page)) {
retval = PTR_ERR(page);
goto out;
}
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
index c550d7d45f2f..ef73ae7c8909 100644
--- a/kernel/module/kallsyms.c
+++ b/kernel/module/kallsyms.c
@@ -381,34 +381,6 @@ out:
return -ERANGE;
}
-int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
- unsigned long *offset, char *modname, char *name)
-{
- struct module *mod;
-
- preempt_disable();
- list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- if (within_module(addr, mod)) {
- const char *sym;
-
- sym = find_kallsyms_symbol(mod, addr, size, offset);
- if (!sym)
- goto out;
- if (modname)
- strscpy(modname, mod->name, MODULE_NAME_LEN);
- if (name)
- strscpy(name, sym, KSYM_NAME_LEN);
- preempt_enable();
- return 0;
- }
- }
-out:
- preempt_enable();
- return -ERANGE;
-}
-
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
char *name, char *module_name, int *exported)
{
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 044aa2c9e3cb..834de86ebe35 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -820,10 +820,8 @@ static struct module_attribute modinfo_refcnt =
void __module_get(struct module *module)
{
if (module) {
- preempt_disable();
atomic_inc(&module->refcnt);
trace_module_get(module, _RET_IP_);
- preempt_enable();
}
}
EXPORT_SYMBOL(__module_get);
@@ -833,15 +831,12 @@ bool try_module_get(struct module *module)
bool ret = true;
if (module) {
- preempt_disable();
/* Note: here, we can fail to get a reference */
if (likely(module_is_live(module) &&
atomic_inc_not_zero(&module->refcnt) != 0))
trace_module_get(module, _RET_IP_);
else
ret = false;
-
- preempt_enable();
}
return ret;
}
@@ -852,11 +847,9 @@ void module_put(struct module *module)
int ret;
if (module) {
- preempt_disable();
ret = atomic_dec_if_positive(&module->refcnt);
WARN_ON(ret < 0); /* Failed to put refcount */
trace_module_put(module, _RET_IP_);
- preempt_enable();
}
}
EXPORT_SYMBOL(module_put);
@@ -1521,14 +1514,14 @@ static void __layout_sections(struct module *mod, struct load_info *info, bool i
MOD_RODATA,
MOD_RO_AFTER_INIT,
MOD_DATA,
- MOD_INVALID, /* This is needed to match the masks array */
+ MOD_DATA,
};
static const int init_m_to_mem_type[] = {
MOD_INIT_TEXT,
MOD_INIT_RODATA,
MOD_INVALID,
MOD_INIT_DATA,
- MOD_INVALID, /* This is needed to match the masks array */
+ MOD_INIT_DATA,
};
for (m = 0; m < ARRAY_SIZE(masks); ++m) {
@@ -3057,26 +3050,83 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
return load_module(&info, uargs, 0);
}
-SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
+struct idempotent {
+ const void *cookie;
+ struct hlist_node entry;
+ struct completion complete;
+ int ret;
+};
+
+#define IDEM_HASH_BITS 8
+static struct hlist_head idem_hash[1 << IDEM_HASH_BITS];
+static DEFINE_SPINLOCK(idem_lock);
+
+static bool idempotent(struct idempotent *u, const void *cookie)
{
+ int hash = hash_ptr(cookie, IDEM_HASH_BITS);
+ struct hlist_head *head = idem_hash + hash;
+ struct idempotent *existing;
+ bool first;
+
+ u->ret = 0;
+ u->cookie = cookie;
+ init_completion(&u->complete);
+
+ spin_lock(&idem_lock);
+ first = true;
+ hlist_for_each_entry(existing, head, entry) {
+ if (existing->cookie != cookie)
+ continue;
+ first = false;
+ break;
+ }
+ hlist_add_head(&u->entry, idem_hash + hash);
+ spin_unlock(&idem_lock);
+
+ return !first;
+}
+
+/*
+ * We were the first one with 'cookie' on the list, and we ended
+ * up completing the operation. We now need to walk the list,
+ * remove everybody - which includes ourselves - fill in the return
+ * value, and then complete the operation.
+ */
+static void idempotent_complete(struct idempotent *u, int ret)
+{
+ const void *cookie = u->cookie;
+ int hash = hash_ptr(cookie, IDEM_HASH_BITS);
+ struct hlist_head *head = idem_hash + hash;
+ struct hlist_node *next;
+ struct idempotent *pos;
+
+ spin_lock(&idem_lock);
+ hlist_for_each_entry_safe(pos, next, head, entry) {
+ if (pos->cookie != cookie)
+ continue;
+ hlist_del(&pos->entry);
+ pos->ret = ret;
+ complete(&pos->complete);
+ }
+ spin_unlock(&idem_lock);
+}
+
+static int init_module_from_file(struct file *f, const char __user * uargs, int flags)
+{
+ struct idempotent idem;
struct load_info info = { };
void *buf = NULL;
- int len;
- int err;
+ int len, ret;
- err = may_init_module();
- if (err)
- return err;
-
- pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
+ if (!f || !(f->f_mode & FMODE_READ))
+ return -EBADF;
- if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
- |MODULE_INIT_IGNORE_VERMAGIC
- |MODULE_INIT_COMPRESSED_FILE))
- return -EINVAL;
+ if (idempotent(&idem, file_inode(f))) {
+ wait_for_completion(&idem.complete);
+ return idem.ret;
+ }
- len = kernel_read_file_from_fd(fd, 0, &buf, INT_MAX, NULL,
- READING_MODULE);
+ len = kernel_read_file(f, 0, &buf, INT_MAX, NULL, READING_MODULE);
if (len < 0) {
mod_stat_inc(&failed_kreads);
mod_stat_add_long(len, &invalid_kread_bytes);
@@ -3084,7 +3134,7 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
}
if (flags & MODULE_INIT_COMPRESSED_FILE) {
- err = module_decompress(&info, buf, len);
+ int err = module_decompress(&info, buf, len);
vfree(buf); /* compressed data is no longer needed */
if (err) {
mod_stat_inc(&failed_decompress);
@@ -3096,7 +3146,31 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
info.len = len;
}
- return load_module(&info, uargs, flags);
+ ret = load_module(&info, uargs, flags);
+ idempotent_complete(&idem, ret);
+ return ret;
+}
+
+SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
+{
+ int err;
+ struct fd f;
+
+ err = may_init_module();
+ if (err)
+ return err;
+
+ pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
+
+ if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
+ |MODULE_INIT_IGNORE_VERMAGIC
+ |MODULE_INIT_COMPRESSED_FILE))
+ return -EINVAL;
+
+ f = fdget(fd);
+ err = init_module_from_file(f.file, uargs, flags);
+ fdput(f);
+ return err;
}
/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
diff --git a/kernel/module/stats.c b/kernel/module/stats.c
index ad7b6ada29f2..6ab2c94d6bc3 100644
--- a/kernel/module/stats.c
+++ b/kernel/module/stats.c
@@ -276,6 +276,7 @@ static ssize_t read_file_mod_stats(struct file *file, char __user *user_buf,
struct mod_fail_load *mod_fail;
unsigned int len, size, count_failed = 0;
char *buf;
+ int ret;
u32 live_mod_count, fkreads, fdecompress, fbecoming, floads;
unsigned long total_size, text_size, ikread_bytes, ibecoming_bytes,
idecompress_bytes, imod_bytes, total_virtual_lost;
@@ -390,8 +391,9 @@ static ssize_t read_file_mod_stats(struct file *file, char __user *user_buf,
out_unlock:
mutex_unlock(&module_mutex);
out:
+ ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
kfree(buf);
- return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+ return ret;
}
#undef MAX_PREAMBLE
#undef MAX_FAILED_MOD_PRINT
generated by cgit (git 2.34.1) at 2024-06-13 22:15:13 +0000