msm: adsprpc: Handle UAF in fastrpc debugfs read

Use lock to protect maps amongst multiple
threads to avoid race condition.

Change-Id: Ib0c83dd38ea8e5acb54a1478d10b02385c27ba31
Signed-off-by: Swathi K <quic_c_kataka@quicinc.com>
This commit is contained in:
Swathi K 2022-01-08 00:33:20 +05:30 • committed by Gerrit - the friendly Code Review server
commit da2bdbc797

View file

@ -5350,6 +5350,7 @@ static ssize_t fastrpc_debugfs_read(struct file *filp, char __user *buffer,
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%s%s%s%s%s\n", single_line, single_line,
single_line, single_line, single_line);
spin_lock(&me->hlock);
hlist_for_each_entry_safe(gmaps, n, &me->maps, hn) {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20d|0x%-18llX|0x%-18X|0x%-20lX\n\n",
@ -5357,18 +5358,21 @@ static ssize_t fastrpc_debugfs_read(struct file *filp, char __user *buffer,
(uint32_t)gmaps->size,
gmaps->va);
}
spin_unlock(&me->hlock);
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20s|%-20s|%-20s|%-20s\n",
"len", "refs", "raddr", "flags");
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%s%s%s%s%s\n", single_line, single_line,
single_line, single_line, single_line);
spin_lock(&me->hlock);
hlist_for_each_entry_safe(gmaps, n, &me->maps, hn) {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"0x%-18X|%-20d|%-20lu|%-20u\n",
(uint32_t)gmaps->len, gmaps->refs,
gmaps->raddr, gmaps->flags);
}
spin_unlock(&me->hlock);
} else {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"\n%s %13s %d\n", "cid", ":", fl->cid);
@ -5410,12 +5414,14 @@ static ssize_t fastrpc_debugfs_read(struct file *filp, char __user *buffer,
"%s%s%s%s%s\n",
single_line, single_line, single_line,
single_line, single_line);
mutex_lock(&fl->map_mutex);
hlist_for_each_entry_safe(map, n, &fl->maps, hn) {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"0x%-20lX|0x%-20llX|0x%-20zu\n\n",
map->va, map->phys,
map->size);
}
mutex_unlock(&fl->map_mutex);
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20s|%-20s|%-20s|%-20s\n",
"len", "refs",
@ -5424,24 +5430,27 @@ static ssize_t fastrpc_debugfs_read(struct file *filp, char __user *buffer,
"%s%s%s%s%s\n",
single_line, single_line, single_line,
single_line, single_line);
mutex_lock(&fl->map_mutex);
hlist_for_each_entry_safe(map, n, &fl->maps, hn) {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20zu|%-20d|0x%-20lX|%-20d\n\n",
map->len, map->refs, map->raddr,
map->uncached);
}
mutex_unlock(&fl->map_mutex);
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20s|%-20s\n", "secure", "attr");
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%s%s%s%s%s\n",
single_line, single_line, single_line,
single_line, single_line);
mutex_lock(&fl->map_mutex);
hlist_for_each_entry_safe(map, n, &fl->maps, hn) {
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"%-20d|0x%-20lX\n\n",
map->secure, map->attr);
}
mutex_unlock(&fl->map_mutex);
len += scnprintf(fileinfo + len, DEBUGFS_SIZE - len,
"\n======%s %s %s======\n", title,
" LIST OF BUFS ", title);