| Message ID | 20201207123720.19111-1-lukas.bulwahn@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | bpf: propagate __user annotations properly | expand |
On 12/7/20 4:37 AM, Lukas Bulwahn wrote: > __htab_map_lookup_and_delete_batch() stores a user pointer in the local > variable ubatch and uses that in copy_{from,to}_user(), but ubatch misses a > __user annotation. > > So, sparse warns in the various assignments and uses of ubatch: > > kernel/bpf/hashtab.c:1415:24: warning: incorrect type in initializer > (different address spaces) > kernel/bpf/hashtab.c:1415:24: expected void *ubatch > kernel/bpf/hashtab.c:1415:24: got void [noderef] __user * > > kernel/bpf/hashtab.c:1444:46: warning: incorrect type in argument 2 > (different address spaces) > kernel/bpf/hashtab.c:1444:46: expected void const [noderef] __user *from > kernel/bpf/hashtab.c:1444:46: got void *ubatch > > kernel/bpf/hashtab.c:1608:16: warning: incorrect type in assignment > (different address spaces) > kernel/bpf/hashtab.c:1608:16: expected void *ubatch > kernel/bpf/hashtab.c:1608:16: got void [noderef] __user * > > kernel/bpf/hashtab.c:1609:26: warning: incorrect type in argument 1 > (different address spaces) > kernel/bpf/hashtab.c:1609:26: expected void [noderef] __user *to > kernel/bpf/hashtab.c:1609:26: got void *ubatch > > Add the __user annotation to repair this chain of propagating __user > annotations in __htab_map_lookup_and_delete_batch(). Add fix tag? Fixes: 057996380a42 ("bpf: Add batch ops to all htab bpf map") > > Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Thanks for the fix. LGTM. I guess either bpf or bpf-next tree is fine since this is not a correctness issue. Acked-by: Yonghong Song <yhs@fb.com>
On Mon, Dec 7, 2020 at 5:12 PM Yonghong Song <yhs@fb.com> wrote: > > > > On 12/7/20 4:37 AM, Lukas Bulwahn wrote: > > __htab_map_lookup_and_delete_batch() stores a user pointer in the local > > variable ubatch and uses that in copy_{from,to}_user(), but ubatch misses a > > __user annotation. > > > > So, sparse warns in the various assignments and uses of ubatch: > > > > kernel/bpf/hashtab.c:1415:24: warning: incorrect type in initializer > > (different address spaces) > > kernel/bpf/hashtab.c:1415:24: expected void *ubatch > > kernel/bpf/hashtab.c:1415:24: got void [noderef] __user * > > > > kernel/bpf/hashtab.c:1444:46: warning: incorrect type in argument 2 > > (different address spaces) > > kernel/bpf/hashtab.c:1444:46: expected void const [noderef] __user *from > > kernel/bpf/hashtab.c:1444:46: got void *ubatch > > > > kernel/bpf/hashtab.c:1608:16: warning: incorrect type in assignment > > (different address spaces) > > kernel/bpf/hashtab.c:1608:16: expected void *ubatch > > kernel/bpf/hashtab.c:1608:16: got void [noderef] __user * > > > > kernel/bpf/hashtab.c:1609:26: warning: incorrect type in argument 1 > > (different address spaces) > > kernel/bpf/hashtab.c:1609:26: expected void [noderef] __user *to > > kernel/bpf/hashtab.c:1609:26: got void *ubatch > > > > Add the __user annotation to repair this chain of propagating __user > > annotations in __htab_map_lookup_and_delete_batch(). > > Add fix tag? > > Fixes: 057996380a42 ("bpf: Add batch ops to all htab bpf map") > Fixes tag can be added by the maintainers when they pick it, but I personally am not a fan of adding a Fixes tag for such a minor fix here. It is purely a syntactic change and change for the sparse semantic parser, but it really does not need to be backported and nothing observable in the binary was broken. That is my rationale for not adding a Fixes: tag here. It is your final call. > > > > Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> > > Thanks for the fix. LGTM. I guess either bpf or bpf-next tree is fine > since this is not a correctness issue. > Agree, and it is no functional change, nor a change in the object code. So risks of regressions are very, very low (zero). Thanks for the review, Lukas
Hello: This patch was applied to bpf/bpf-next.git (refs/heads/master): On Mon, 7 Dec 2020 13:37:20 +0100 you wrote: > __htab_map_lookup_and_delete_batch() stores a user pointer in the local > variable ubatch and uses that in copy_{from,to}_user(), but ubatch misses a > __user annotation. > > So, sparse warns in the various assignments and uses of ubatch: > > kernel/bpf/hashtab.c:1415:24: warning: incorrect type in initializer > (different address spaces) > kernel/bpf/hashtab.c:1415:24: expected void *ubatch > kernel/bpf/hashtab.c:1415:24: got void [noderef] __user * > > [...] Here is the summary with links: - bpf: propagate __user annotations properly https://git.kernel.org/bpf/bpf-next/c/2f4b03195fe8 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index fe7a0733a63a..76c791def033 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -1412,7 +1412,7 @@ __htab_map_lookup_and_delete_batch(struct bpf_map *map, void *keys = NULL, *values = NULL, *value, *dst_key, *dst_val; void __user *uvalues = u64_to_user_ptr(attr->batch.values); void __user *ukeys = u64_to_user_ptr(attr->batch.keys); - void *ubatch = u64_to_user_ptr(attr->batch.in_batch); + void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); u32 batch, max_count, size, bucket_size; struct htab_elem *node_to_free = NULL; u64 elem_map_flags, map_flags;
__htab_map_lookup_and_delete_batch() stores a user pointer in the local variable ubatch and uses that in copy_{from,to}_user(), but ubatch misses a __user annotation. So, sparse warns in the various assignments and uses of ubatch: kernel/bpf/hashtab.c:1415:24: warning: incorrect type in initializer (different address spaces) kernel/bpf/hashtab.c:1415:24: expected void *ubatch kernel/bpf/hashtab.c:1415:24: got void [noderef] __user * kernel/bpf/hashtab.c:1444:46: warning: incorrect type in argument 2 (different address spaces) kernel/bpf/hashtab.c:1444:46: expected void const [noderef] __user *from kernel/bpf/hashtab.c:1444:46: got void *ubatch kernel/bpf/hashtab.c:1608:16: warning: incorrect type in assignment (different address spaces) kernel/bpf/hashtab.c:1608:16: expected void *ubatch kernel/bpf/hashtab.c:1608:16: got void [noderef] __user * kernel/bpf/hashtab.c:1609:26: warning: incorrect type in argument 1 (different address spaces) kernel/bpf/hashtab.c:1609:26: expected void [noderef] __user *to kernel/bpf/hashtab.c:1609:26: got void *ubatch Add the __user annotation to repair this chain of propagating __user annotations in __htab_map_lookup_and_delete_batch(). Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> --- applies cleanly on current master (v5.10-rc7) and next-20201204 BPF maintainers, please pick this minor non-urgent clean-up patch. kernel/bpf/hashtab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)