bpf: Use safer kvmalloc_array() where possible
The kvmalloc_array() function is safer because it has a check for
integer overflows. These sizes come from the user and I was not
able to see any bounds checking so an integer overflow seems like a
realistic concern.
Fixes: 0dcac2725406 ("bpf: Add multi kprobe link")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/Yo9VRVMeHbALyjUH@kili
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 10b157a..7a13e6a 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2263,11 +2263,11 @@ static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32
int err = -ENOMEM;
unsigned int i;
- syms = kvmalloc(cnt * sizeof(*syms), GFP_KERNEL);
+ syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
if (!syms)
goto error;
- buf = kvmalloc(cnt * KSYM_NAME_LEN, GFP_KERNEL);
+ buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
if (!buf)
goto error;
@@ -2464,7 +2464,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
return -EINVAL;
size = cnt * sizeof(*addrs);
- addrs = kvmalloc(size, GFP_KERNEL);
+ addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
if (!addrs)
return -ENOMEM;
@@ -2489,7 +2489,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
if (ucookies) {
- cookies = kvmalloc(size, GFP_KERNEL);
+ cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
if (!cookies) {
err = -ENOMEM;
goto error;
