| Message ID | 154693980088.104235.16222977463502002037.stgit@buzz |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | net/core/neighbour: tell kmemleak about hash tables | expand |
On 01/08/2019 01:30 AM, Konstantin Khlebnikov wrote: > This fixes false-positive kmemleak reports about leaked neighbour entries: > > unreferenced object 0xffff8885c6e4d0a8 (size 1024): size 1024 object : should have been allocated by kzalloc(), right ? > comm "softirq", pid 0, jiffies 4294922664 (age 167640.804s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 20 2c f3 83 ff ff ff ff ........ ,...... > 08 c0 ef 5f 84 88 ff ff 01 8c 7d 02 01 00 00 00 ..._......}..... > backtrace: > [<00000000748509fe>] ip6_finish_output2+0x887/0x1e40 > [<0000000036d7a0d8>] ip6_output+0x1ba/0x600 > [<0000000027ea7dba>] ip6_send_skb+0x92/0x2f0 > [<00000000d6e2111d>] udp_v6_send_skb.isra.24+0x680/0x15e0 > [<000000000668a8be>] udpv6_sendmsg+0x18c9/0x27a0 > [<000000004bd5fa90>] sock_sendmsg+0xb3/0xf0 > [<000000008227b29f>] ___sys_sendmsg+0x745/0x8f0 > [<000000008698009d>] __sys_sendmsg+0xde/0x170 > [<00000000889dacf1>] do_syscall_64+0x9b/0x400 > [<0000000081cdb353>] entry_SYSCALL_64_after_hwframe+0x49/0xbe > [<000000005767ed39>] 0xffffffffffffffff > > Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> > --- > net/core/neighbour.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/net/core/neighbour.c b/net/core/neighbour.c > index 763a7b08df67..3e27a779f288 100644 > --- a/net/core/neighbour.c > +++ b/net/core/neighbour.c > @@ -18,6 +18,7 @@ > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > #include <linux/slab.h> > +#include <linux/kmemleak.h> > #include <linux/types.h> > #include <linux/kernel.h> > #include <linux/module.h> > @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) > ret = kmalloc(sizeof(*ret), GFP_ATOMIC); > if (!ret) > return NULL; > - if (size <= PAGE_SIZE) > + if (size <= PAGE_SIZE) { > buckets = kzalloc(size, GFP_ATOMIC); > - else > + } else { > buckets = (struct neighbour __rcu **) > __get_free_pages(GFP_ATOMIC | __GFP_ZERO, > get_order(size)); > + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); > + } > if (!buckets) { > kfree(ret); > return NULL; > @@ -468,10 +471,12 @@ static void neigh_hash_free_rcu(struct rcu_head *head) > size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); > struct neighbour __rcu **buckets = nht->hash_buckets; > > - if (size <= PAGE_SIZE) > + if (size <= PAGE_SIZE) { > kfree(buckets); > - else > + } else { > + kmemleak_free(buckets); > free_pages((unsigned long)buckets, get_order(size)); > + } > kfree(nht); > } > >
On 08.01.2019 14:59, Eric Dumazet wrote: > > > On 01/08/2019 01:30 AM, Konstantin Khlebnikov wrote: >> This fixes false-positive kmemleak reports about leaked neighbour entries: >> >> unreferenced object 0xffff8885c6e4d0a8 (size 1024): > > > size 1024 object : should have been allocated by kzalloc(), right ? Yep, neigh_alloc calls kzalloc. Size might be bloated by lockdep. > >> comm "softirq", pid 0, jiffies 4294922664 (age 167640.804s) >> hex dump (first 32 bytes): >> 00 00 00 00 00 00 00 00 20 2c f3 83 ff ff ff ff ........ ,...... >> 08 c0 ef 5f 84 88 ff ff 01 8c 7d 02 01 00 00 00 ..._......}..... >> backtrace: >> [<00000000748509fe>] ip6_finish_output2+0x887/0x1e40 >> [<0000000036d7a0d8>] ip6_output+0x1ba/0x600 >> [<0000000027ea7dba>] ip6_send_skb+0x92/0x2f0 >> [<00000000d6e2111d>] udp_v6_send_skb.isra.24+0x680/0x15e0 >> [<000000000668a8be>] udpv6_sendmsg+0x18c9/0x27a0 >> [<000000004bd5fa90>] sock_sendmsg+0xb3/0xf0 >> [<000000008227b29f>] ___sys_sendmsg+0x745/0x8f0 >> [<000000008698009d>] __sys_sendmsg+0xde/0x170 >> [<00000000889dacf1>] do_syscall_64+0x9b/0x400 >> [<0000000081cdb353>] entry_SYSCALL_64_after_hwframe+0x49/0xbe >> [<000000005767ed39>] 0xffffffffffffffff >> >> Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> >> --- >> net/core/neighbour.c | 13 +++++++++---- >> 1 file changed, 9 insertions(+), 4 deletions(-) >> >> diff --git a/net/core/neighbour.c b/net/core/neighbour.c >> index 763a7b08df67..3e27a779f288 100644 >> --- a/net/core/neighbour.c >> +++ b/net/core/neighbour.c >> @@ -18,6 +18,7 @@ >> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt >> >> #include <linux/slab.h> >> +#include <linux/kmemleak.h> >> #include <linux/types.h> >> #include <linux/kernel.h> >> #include <linux/module.h> >> @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) >> ret = kmalloc(sizeof(*ret), GFP_ATOMIC); >> if (!ret) >> return NULL; >> - if (size <= PAGE_SIZE) >> + if (size <= PAGE_SIZE) { >> buckets = kzalloc(size, GFP_ATOMIC); >> - else >> + } else { >> buckets = (struct neighbour __rcu **) >> __get_free_pages(GFP_ATOMIC | __GFP_ZERO, >> get_order(size)); >> + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); >> + } >> if (!buckets) { >> kfree(ret); >> return NULL; >> @@ -468,10 +471,12 @@ static void neigh_hash_free_rcu(struct rcu_head *head) >> size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); >> struct neighbour __rcu **buckets = nht->hash_buckets; >> >> - if (size <= PAGE_SIZE) >> + if (size <= PAGE_SIZE) { >> kfree(buckets); >> - else >> + } else { >> + kmemleak_free(buckets); >> free_pages((unsigned long)buckets, get_order(size)); >> + } >> kfree(nht); >> } >> >>
From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Date: Tue, 08 Jan 2019 12:30:00 +0300 > This fixes false-positive kmemleak reports about leaked neighbour entries: ... > Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Applied.
On Tue, Jan 8, 2019 at 1:30 AM Konstantin Khlebnikov <khlebnikov@yandex-team.ru> wrote: > @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) > ret = kmalloc(sizeof(*ret), GFP_ATOMIC); > if (!ret) > return NULL; > - if (size <= PAGE_SIZE) > + if (size <= PAGE_SIZE) { > buckets = kzalloc(size, GFP_ATOMIC); > - else > + } else { > buckets = (struct neighbour __rcu **) > __get_free_pages(GFP_ATOMIC | __GFP_ZERO, > get_order(size)); > + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); Why min_count is 0 rather than 1 here?
On Thu, Jan 10, 2019 at 11:45 PM Cong Wang <xiyou.wangcong@gmail.com> wrote: > > On Tue, Jan 8, 2019 at 1:30 AM Konstantin Khlebnikov > <khlebnikov@yandex-team.ru> wrote: > > @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) > > ret = kmalloc(sizeof(*ret), GFP_ATOMIC); > > if (!ret) > > return NULL; > > - if (size <= PAGE_SIZE) > > + if (size <= PAGE_SIZE) { > > buckets = kzalloc(size, GFP_ATOMIC); > > - else > > + } else { > > buckets = (struct neighbour __rcu **) > > __get_free_pages(GFP_ATOMIC | __GFP_ZERO, > > get_order(size)); > > + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); > > Why min_count is 0 rather than 1 here? The api isn't clear and I've misread description. So it should be 1 for reporting leak of hash table itself. But 0 doesn't add any new issues.
On Fri, Jan 11, 2019 at 07:26:09AM +0300, Konstantin Khlebnikov wrote: > On Thu, Jan 10, 2019 at 11:45 PM Cong Wang <xiyou.wangcong@gmail.com> wrote: > > On Tue, Jan 8, 2019 at 1:30 AM Konstantin Khlebnikov > > <khlebnikov@yandex-team.ru> wrote: > > > @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) > > > ret = kmalloc(sizeof(*ret), GFP_ATOMIC); > > > if (!ret) > > > return NULL; > > > - if (size <= PAGE_SIZE) > > > + if (size <= PAGE_SIZE) { > > > buckets = kzalloc(size, GFP_ATOMIC); > > > - else > > > + } else { > > > buckets = (struct neighbour __rcu **) > > > __get_free_pages(GFP_ATOMIC | __GFP_ZERO, > > > get_order(size)); > > > + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); > > > > Why min_count is 0 rather than 1 here? > > The api isn't clear and I've misread description. > So it should be 1 for reporting leak of hash table itself. > But 0 doesn't add any new issues. Correct. I'd say it makes sense to set it to 1 so that you'd have similar behaviour to the kzalloc() allocation.
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 763a7b08df67..3e27a779f288 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -18,6 +18,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/slab.h> +#include <linux/kmemleak.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/module.h> @@ -443,12 +444,14 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) ret = kmalloc(sizeof(*ret), GFP_ATOMIC); if (!ret) return NULL; - if (size <= PAGE_SIZE) + if (size <= PAGE_SIZE) { buckets = kzalloc(size, GFP_ATOMIC); - else + } else { buckets = (struct neighbour __rcu **) __get_free_pages(GFP_ATOMIC | __GFP_ZERO, get_order(size)); + kmemleak_alloc(buckets, size, 0, GFP_ATOMIC); + } if (!buckets) { kfree(ret); return NULL; @@ -468,10 +471,12 @@ static void neigh_hash_free_rcu(struct rcu_head *head) size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); struct neighbour __rcu **buckets = nht->hash_buckets; - if (size <= PAGE_SIZE) + if (size <= PAGE_SIZE) { kfree(buckets); - else + } else { + kmemleak_free(buckets); free_pages((unsigned long)buckets, get_order(size)); + } kfree(nht); }
This fixes false-positive kmemleak reports about leaked neighbour entries: unreferenced object 0xffff8885c6e4d0a8 (size 1024): comm "softirq", pid 0, jiffies 4294922664 (age 167640.804s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 20 2c f3 83 ff ff ff ff ........ ,...... 08 c0 ef 5f 84 88 ff ff 01 8c 7d 02 01 00 00 00 ..._......}..... backtrace: [<00000000748509fe>] ip6_finish_output2+0x887/0x1e40 [<0000000036d7a0d8>] ip6_output+0x1ba/0x600 [<0000000027ea7dba>] ip6_send_skb+0x92/0x2f0 [<00000000d6e2111d>] udp_v6_send_skb.isra.24+0x680/0x15e0 [<000000000668a8be>] udpv6_sendmsg+0x18c9/0x27a0 [<000000004bd5fa90>] sock_sendmsg+0xb3/0xf0 [<000000008227b29f>] ___sys_sendmsg+0x745/0x8f0 [<000000008698009d>] __sys_sendmsg+0xde/0x170 [<00000000889dacf1>] do_syscall_64+0x9b/0x400 [<0000000081cdb353>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<000000005767ed39>] 0xffffffffffffffff Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> --- net/core/neighbour.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)