| Message ID | 20240730160449.368698-1-dmantipov@yandex.ru (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | net: core: use __counted_by for trailing VLA of struct sock_reuseport | expand |
On 30/07/24 10:04, Dmitry Antipov wrote: > According to '__reuseport_alloc()', annotate trailing VLA 'sock' of `socks` is a flexible-array member[1], not a VLA[2]. > 'struct sock_reuseport' with '__counted_by()' and use convenient > 'struct_size()' to simplify the math used in 'kzalloc()'. > > Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Looks correct. Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> > --- > include/net/sock_reuseport.h | 2 +- > net/core/sock_reuseport.c | 7 +++---- > 2 files changed, 4 insertions(+), 5 deletions(-) > > diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h > index 6ec140b0a61b..6e4faf3ee76f 100644 > --- a/include/net/sock_reuseport.h > +++ b/include/net/sock_reuseport.h > @@ -26,7 +26,7 @@ struct sock_reuseport { > unsigned int bind_inany:1; > unsigned int has_conns:1; > struct bpf_prog __rcu *prog; /* optional BPF sock selector */ > - struct sock *socks[]; /* array of sock pointers */ > + struct sock *socks[] __counted_by(max_socks); > }; > > extern int reuseport_alloc(struct sock *sk, bool bind_inany); > diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c > index 5a165286e4d8..5eea73aaeb0f 100644 > --- a/net/core/sock_reuseport.c > +++ b/net/core/sock_reuseport.c > @@ -173,11 +173,10 @@ static bool __reuseport_detach_closed_sock(struct sock *sk, > > static struct sock_reuseport *__reuseport_alloc(unsigned int max_socks) > { > - unsigned int size = sizeof(struct sock_reuseport) + > - sizeof(struct sock *) * max_socks; > - struct sock_reuseport *reuse = kzalloc(size, GFP_ATOMIC); > + struct sock_reuseport *reuse = > + kzalloc(struct_size(reuse, socks, max_socks), GFP_ATOMIC); > > - if (!reuse) > + if (unlikely(!reuse)) > return NULL; > > reuse->max_socks = max_socks; Thanks -- Gustavo [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html
From: Dmitry Antipov <dmantipov@yandex.ru> Date: Tue, 30 Jul 2024 19:04:49 +0300 > According to '__reuseport_alloc()', annotate trailing VLA 'sock' of > 'struct sock_reuseport' with '__counted_by()' and use convenient > 'struct_size()' to simplify the math used in 'kzalloc()'. > > Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
On Tue, 30 Jul 2024 19:04:49 +0300 Dmitry Antipov wrote: > - unsigned int size = sizeof(struct sock_reuseport) + > - sizeof(struct sock *) * max_socks; > - struct sock_reuseport *reuse = kzalloc(size, GFP_ATOMIC); > + struct sock_reuseport *reuse = > + kzalloc(struct_size(reuse, socks, max_socks), GFP_ATOMIC); > please move the function call out of the init. It doesn't fit on a single line so what's the point.. > - if (!reuse) > + if (unlikely(!reuse)) And why add the unlikely here? Seems unrelated..
diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h index 6ec140b0a61b..6e4faf3ee76f 100644 --- a/include/net/sock_reuseport.h +++ b/include/net/sock_reuseport.h @@ -26,7 +26,7 @@ struct sock_reuseport { unsigned int bind_inany:1; unsigned int has_conns:1; struct bpf_prog __rcu *prog; /* optional BPF sock selector */ - struct sock *socks[]; /* array of sock pointers */ + struct sock *socks[] __counted_by(max_socks); }; extern int reuseport_alloc(struct sock *sk, bool bind_inany); diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index 5a165286e4d8..5eea73aaeb0f 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -173,11 +173,10 @@ static bool __reuseport_detach_closed_sock(struct sock *sk, static struct sock_reuseport *__reuseport_alloc(unsigned int max_socks) { - unsigned int size = sizeof(struct sock_reuseport) + - sizeof(struct sock *) * max_socks; - struct sock_reuseport *reuse = kzalloc(size, GFP_ATOMIC); + struct sock_reuseport *reuse = + kzalloc(struct_size(reuse, socks, max_socks), GFP_ATOMIC); - if (!reuse) + if (unlikely(!reuse)) return NULL; reuse->max_socks = max_socks;
According to '__reuseport_alloc()', annotate trailing VLA 'sock' of 'struct sock_reuseport' with '__counted_by()' and use convenient 'struct_size()' to simplify the math used in 'kzalloc()'. Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> --- include/net/sock_reuseport.h | 2 +- net/core/sock_reuseport.c | 7 +++---- 2 files changed, 4 insertions(+), 5 deletions(-)