| Message ID | 20200224212643.30672-1-s-anna@ti.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | f13f09a12cbd0c7b776e083c5d008b6c6a9c4e0b |
| Headers | show |
| Series | virtio_ring: Fix mem leak with vring_new_virtqueue() | expand |
On 2020/2/25 上午5:26, Suman Anna wrote: > The functions vring_new_virtqueue() and __vring_new_virtqueue() are used > with split rings, and any allocations within these functions are managed > outside of the .we_own_ring flag. The commit cbeedb72b97a ("virtio_ring: > allocate desc state for split ring separately") allocates the desc state > within the __vring_new_virtqueue() but frees it only when the .we_own_ring > flag is set. This leads to a memory leak when freeing such allocated > virtqueues with the vring_del_virtqueue() function. > > Fix this by moving the desc_state free code outside the flag and only > for split rings. Issue was discovered during testing with remoteproc > and virtio_rpmsg. > > Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring separately") > Signed-off-by: Suman Anna <s-anna@ti.com> > --- > drivers/virtio/virtio_ring.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 867c7ebd3f10..58b96baa8d48 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) > vq->split.queue_size_in_bytes, > vq->split.vring.desc, > vq->split.queue_dma_addr); > - > - kfree(vq->split.desc_state); > } > } > + if (!vq->packed_ring) > + kfree(vq->split.desc_state); Nitpick, it looks to me it would be more clear if we just free desc_state unconditionally here (and remove the kfree for packed above). Anyway desc_state will be allocated by use even if !we_own_ring. Thanks > list_del(&_vq->list); > kfree(vq); > }
Hi Jason, On 2/24/20 11:39 PM, Jason Wang wrote: > > On 2020/2/25 上午5:26, Suman Anna wrote: >> The functions vring_new_virtqueue() and __vring_new_virtqueue() are used >> with split rings, and any allocations within these functions are managed >> outside of the .we_own_ring flag. The commit cbeedb72b97a ("virtio_ring: >> allocate desc state for split ring separately") allocates the desc state >> within the __vring_new_virtqueue() but frees it only when the >> .we_own_ring >> flag is set. This leads to a memory leak when freeing such allocated >> virtqueues with the vring_del_virtqueue() function. >> >> Fix this by moving the desc_state free code outside the flag and only >> for split rings. Issue was discovered during testing with remoteproc >> and virtio_rpmsg. >> >> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring >> separately") >> Signed-off-by: Suman Anna <s-anna@ti.com> >> --- >> drivers/virtio/virtio_ring.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c >> index 867c7ebd3f10..58b96baa8d48 100644 >> --- a/drivers/virtio/virtio_ring.c >> +++ b/drivers/virtio/virtio_ring.c >> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) >> vq->split.queue_size_in_bytes, >> vq->split.vring.desc, >> vq->split.queue_dma_addr); >> - >> - kfree(vq->split.desc_state); >> } >> } >> + if (!vq->packed_ring) >> + kfree(vq->split.desc_state); > > > Nitpick, it looks to me it would be more clear if we just free > desc_state unconditionally here (and remove the kfree for packed above). OK, are you sure you want that to be folded into this patch? It looks to me a separate cleanup/consolidation patch, and packed desc_state does not suffer this memleak, and need not be backported into stable kernels. regards Suman > Anyway desc_state will be allocated by use even if !we_own_ring. > > Thanks > > >> list_del(&_vq->list); >> kfree(vq); >> } >
On 2020/2/26 上午12:51, Suman Anna wrote: > Hi Jason, > > On 2/24/20 11:39 PM, Jason Wang wrote: >> On 2020/2/25 上午5:26, Suman Anna wrote: >>> The functions vring_new_virtqueue() and __vring_new_virtqueue() are used >>> with split rings, and any allocations within these functions are managed >>> outside of the .we_own_ring flag. The commit cbeedb72b97a ("virtio_ring: >>> allocate desc state for split ring separately") allocates the desc state >>> within the __vring_new_virtqueue() but frees it only when the >>> .we_own_ring >>> flag is set. This leads to a memory leak when freeing such allocated >>> virtqueues with the vring_del_virtqueue() function. >>> >>> Fix this by moving the desc_state free code outside the flag and only >>> for split rings. Issue was discovered during testing with remoteproc >>> and virtio_rpmsg. >>> >>> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring >>> separately") >>> Signed-off-by: Suman Anna<s-anna@ti.com> >>> --- >>> drivers/virtio/virtio_ring.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c >>> index 867c7ebd3f10..58b96baa8d48 100644 >>> --- a/drivers/virtio/virtio_ring.c >>> +++ b/drivers/virtio/virtio_ring.c >>> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) >>> vq->split.queue_size_in_bytes, >>> vq->split.vring.desc, >>> vq->split.queue_dma_addr); >>> - >>> - kfree(vq->split.desc_state); >>> } >>> } >>> + if (!vq->packed_ring) >>> + kfree(vq->split.desc_state); >> Nitpick, it looks to me it would be more clear if we just free >> desc_state unconditionally here (and remove the kfree for packed above). > OK, are you sure you want that to be folded into this patch? It looks to > me a separate cleanup/consolidation patch, and packed desc_state does > not suffer this memleak, and need not be backported into stable kernels. > > regards > Suman Though it's just a small tweak, I'm fine for leaving it for future. So Acked-by: Jason Wang <jasowang@redhat.com> Thanks
On 2/25/20 9:13 PM, Jason Wang wrote: > > On 2020/2/26 上午12:51, Suman Anna wrote: >> Hi Jason, >> >> On 2/24/20 11:39 PM, Jason Wang wrote: >>> On 2020/2/25 上午5:26, Suman Anna wrote: >>>> The functions vring_new_virtqueue() and __vring_new_virtqueue() are >>>> used >>>> with split rings, and any allocations within these functions are >>>> managed >>>> outside of the .we_own_ring flag. The commit cbeedb72b97a >>>> ("virtio_ring: >>>> allocate desc state for split ring separately") allocates the desc >>>> state >>>> within the __vring_new_virtqueue() but frees it only when the >>>> .we_own_ring >>>> flag is set. This leads to a memory leak when freeing such allocated >>>> virtqueues with the vring_del_virtqueue() function. >>>> >>>> Fix this by moving the desc_state free code outside the flag and only >>>> for split rings. Issue was discovered during testing with remoteproc >>>> and virtio_rpmsg. >>>> >>>> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring >>>> separately") >>>> Signed-off-by: Suman Anna<s-anna@ti.com> >>>> --- >>>> drivers/virtio/virtio_ring.c | 4 ++-- >>>> 1 file changed, 2 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/virtio/virtio_ring.c >>>> b/drivers/virtio/virtio_ring.c >>>> index 867c7ebd3f10..58b96baa8d48 100644 >>>> --- a/drivers/virtio/virtio_ring.c >>>> +++ b/drivers/virtio/virtio_ring.c >>>> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) >>>> vq->split.queue_size_in_bytes, >>>> vq->split.vring.desc, >>>> vq->split.queue_dma_addr); >>>> - >>>> - kfree(vq->split.desc_state); >>>> } >>>> } >>>> + if (!vq->packed_ring) >>>> + kfree(vq->split.desc_state); >>> Nitpick, it looks to me it would be more clear if we just free >>> desc_state unconditionally here (and remove the kfree for packed above). >> OK, are you sure you want that to be folded into this patch? It looks to >> me a separate cleanup/consolidation patch, and packed desc_state does >> not suffer this memleak, and need not be backported into stable kernels. >> >> regards >> Suman > > > Though it's just a small tweak, I'm fine for leaving it for future. > > So > > Acked-by: Jason Wang <jasowang@redhat.com> Thanks Jason, will post a patch for the same once this is merged. regards Suman
On 2/25/20 9:13 PM, Jason Wang wrote: > > On 2020/2/26 上午12:51, Suman Anna wrote: >> Hi Jason, >> >> On 2/24/20 11:39 PM, Jason Wang wrote: >>> On 2020/2/25 上午5:26, Suman Anna wrote: >>>> The functions vring_new_virtqueue() and __vring_new_virtqueue() are >>>> used >>>> with split rings, and any allocations within these functions are >>>> managed >>>> outside of the .we_own_ring flag. The commit cbeedb72b97a >>>> ("virtio_ring: >>>> allocate desc state for split ring separately") allocates the desc >>>> state >>>> within the __vring_new_virtqueue() but frees it only when the >>>> .we_own_ring >>>> flag is set. This leads to a memory leak when freeing such allocated >>>> virtqueues with the vring_del_virtqueue() function. >>>> >>>> Fix this by moving the desc_state free code outside the flag and only >>>> for split rings. Issue was discovered during testing with remoteproc >>>> and virtio_rpmsg. >>>> >>>> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring >>>> separately") >>>> Signed-off-by: Suman Anna<s-anna@ti.com> >>>> --- >>>> drivers/virtio/virtio_ring.c | 4 ++-- >>>> 1 file changed, 2 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/virtio/virtio_ring.c >>>> b/drivers/virtio/virtio_ring.c >>>> index 867c7ebd3f10..58b96baa8d48 100644 >>>> --- a/drivers/virtio/virtio_ring.c >>>> +++ b/drivers/virtio/virtio_ring.c >>>> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) >>>> vq->split.queue_size_in_bytes, >>>> vq->split.vring.desc, >>>> vq->split.queue_dma_addr); >>>> - >>>> - kfree(vq->split.desc_state); >>>> } >>>> } >>>> + if (!vq->packed_ring) >>>> + kfree(vq->split.desc_state); >>> Nitpick, it looks to me it would be more clear if we just free >>> desc_state unconditionally here (and remove the kfree for packed above). >> OK, are you sure you want that to be folded into this patch? It looks to >> me a separate cleanup/consolidation patch, and packed desc_state does >> not suffer this memleak, and need not be backported into stable kernels. >> >> regards >> Suman > > > Though it's just a small tweak, I'm fine for leaving it for future. > > So > > Acked-by: Jason Wang <jasowang@redhat.com> > Mike, Ping on this. I don't see the patch in -next yet. Can we get this into the current -rc please? regards Suman
On Thu, Mar 05, 2020 at 06:27:53PM -0600, Suman Anna wrote: > On 2/25/20 9:13 PM, Jason Wang wrote: > > > > On 2020/2/26 上午12:51, Suman Anna wrote: > >> Hi Jason, > >> > >> On 2/24/20 11:39 PM, Jason Wang wrote: > >>> On 2020/2/25 上午5:26, Suman Anna wrote: > >>>> The functions vring_new_virtqueue() and __vring_new_virtqueue() are > >>>> used > >>>> with split rings, and any allocations within these functions are > >>>> managed > >>>> outside of the .we_own_ring flag. The commit cbeedb72b97a > >>>> ("virtio_ring: > >>>> allocate desc state for split ring separately") allocates the desc > >>>> state > >>>> within the __vring_new_virtqueue() but frees it only when the > >>>> .we_own_ring > >>>> flag is set. This leads to a memory leak when freeing such allocated > >>>> virtqueues with the vring_del_virtqueue() function. > >>>> > >>>> Fix this by moving the desc_state free code outside the flag and only > >>>> for split rings. Issue was discovered during testing with remoteproc > >>>> and virtio_rpmsg. > >>>> > >>>> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring > >>>> separately") > >>>> Signed-off-by: Suman Anna<s-anna@ti.com> > >>>> --- > >>>> drivers/virtio/virtio_ring.c | 4 ++-- > >>>> 1 file changed, 2 insertions(+), 2 deletions(-) > >>>> > >>>> diff --git a/drivers/virtio/virtio_ring.c > >>>> b/drivers/virtio/virtio_ring.c > >>>> index 867c7ebd3f10..58b96baa8d48 100644 > >>>> --- a/drivers/virtio/virtio_ring.c > >>>> +++ b/drivers/virtio/virtio_ring.c > >>>> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) > >>>> vq->split.queue_size_in_bytes, > >>>> vq->split.vring.desc, > >>>> vq->split.queue_dma_addr); > >>>> - > >>>> - kfree(vq->split.desc_state); > >>>> } > >>>> } > >>>> + if (!vq->packed_ring) > >>>> + kfree(vq->split.desc_state); > >>> Nitpick, it looks to me it would be more clear if we just free > >>> desc_state unconditionally here (and remove the kfree for packed above). > >> OK, are you sure you want that to be folded into this patch? It looks to > >> me a separate cleanup/consolidation patch, and packed desc_state does > >> not suffer this memleak, and need not be backported into stable kernels. > >> > >> regards > >> Suman > > > > > > Though it's just a small tweak, I'm fine for leaving it for future. > > > > So > > > > Acked-by: Jason Wang <jasowang@redhat.com> > > > > Mike, > Ping on this. I don't see the patch in -next yet. Can we get this into > the current -rc please? > > regards > Suman Yes will queue it shortly, thanks!
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 867c7ebd3f10..58b96baa8d48 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) vq->split.queue_size_in_bytes, vq->split.vring.desc, vq->split.queue_dma_addr); - - kfree(vq->split.desc_state); } } + if (!vq->packed_ring) + kfree(vq->split.desc_state); list_del(&_vq->list); kfree(vq); }
The functions vring_new_virtqueue() and __vring_new_virtqueue() are used with split rings, and any allocations within these functions are managed outside of the .we_own_ring flag. The commit cbeedb72b97a ("virtio_ring: allocate desc state for split ring separately") allocates the desc state within the __vring_new_virtqueue() but frees it only when the .we_own_ring flag is set. This leads to a memory leak when freeing such allocated virtqueues with the vring_del_virtqueue() function. Fix this by moving the desc_state free code outside the flag and only for split rings. Issue was discovered during testing with remoteproc and virtio_rpmsg. Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring separately") Signed-off-by: Suman Anna <s-anna@ti.com> --- drivers/virtio/virtio_ring.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)