--- /dev/null
+From 6c7cb60bff7aec24b834343ff433125f469886a3 Mon Sep 17 00:00:00 2001
+From: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
+Date: Fri, 11 Mar 2022 17:13:17 +0000
+Subject: ARM: fix Thumb2 regression with Spectre BHB
+
+From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
+
+commit 6c7cb60bff7aec24b834343ff433125f469886a3 upstream.
+
+When building for Thumb2, the vectors make use of a local label. Sadly,
+the Spectre BHB code also uses a local label with the same number which
+results in the Thumb2 reference pointing at the wrong place. Fix this
+by changing the number used for the Spectre BHB local label.
+
+Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround")
+Tested-by: Nathan Chancellor <nathan@kernel.org>
+Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/arm/kernel/entry-armv.S | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/arch/arm/kernel/entry-armv.S
++++ b/arch/arm/kernel/entry-armv.S
+@@ -1043,9 +1043,9 @@ vector_bhb_loop8_\name:
+
+ @ bhb workaround
+ mov r0, #8
+-1: b . + 4
++3: b . + 4
+ subs r0, r0, #1
+- bne 1b
++ bne 3b
+ dsb
+ isb
+ b 2b
mmc-meson-fix-usage-of-meson_mmc_post_req.patch
riscv-fix-auipc-jalr-relocation-range-checks.patch
arm64-dts-marvell-armada-37xx-remap-io-space-to-bus-address-0x0.patch
+virtio-unexport-virtio_finalize_features.patch
+virtio-acknowledge-all-features-before-access.patch
+watch_queue-pipe-free-watchqueue-state-after-clearing-pipe-ring.patch
+watch_queue-fix-to-release-page-in-release.patch
+watch_queue-fix-to-always-request-a-pow-of-2-pipe-ring-size.patch
+watch_queue-fix-the-alloc-bitmap-size-to-reflect-notes-allocated.patch
+watch_queue-free-the-alloc-bitmap-when-the-watch_queue-is-torn-down.patch
+watch_queue-fix-lack-of-barrier-sync-lock-between-post-and-read.patch
+watch_queue-make-comment-about-setting-defunct-more-accurate.patch
+arm-fix-thumb2-regression-with-spectre-bhb.patch
+watch_queue-fix-filter-limit-check.patch
--- /dev/null
+From 4fa59ede95195f267101a1b8916992cf3f245cdb Mon Sep 17 00:00:00 2001
+From: "Michael S. Tsirkin" <mst@redhat.com>
+Date: Fri, 14 Jan 2022 14:58:41 -0500
+Subject: virtio: acknowledge all features before access
+
+From: Michael S. Tsirkin <mst@redhat.com>
+
+commit 4fa59ede95195f267101a1b8916992cf3f245cdb upstream.
+
+The feature negotiation was designed in a way that
+makes it possible for devices to know which config
+fields will be accessed by drivers.
+
+This is broken since commit 404123c2db79 ("virtio: allow drivers to
+validate features") with fallout in at least block and net. We have a
+partial work-around in commit 2f9a174f918e ("virtio: write back
+F_VERSION_1 before validate") which at least lets devices find out which
+format should config space have, but this is a partial fix: guests
+should not access config space without acknowledging features since
+otherwise we'll never be able to change the config space format.
+
+To fix, split finalize_features from virtio_finalize_features and
+call finalize_features with all feature bits before validation,
+and then - if validation changed any bits - once again after.
+
+Since virtio_finalize_features no longer writes out features
+rename it to virtio_features_ok - since that is what it does:
+checks that features are ok with the device.
+
+As a side effect, this also reduces the amount of hypervisor accesses -
+we now only acknowledge features once unless we are clearing any
+features when validating (which is uncommon).
+
+IRC I think that this was more or less always the intent in the spec but
+unfortunately the way the spec is worded does not say this explicitly, I
+plan to address this at the spec level, too.
+
+Acked-by: Jason Wang <jasowang@redhat.com>
+Cc: stable@vger.kernel.org
+Fixes: 404123c2db79 ("virtio: allow drivers to validate features")
+Fixes: 2f9a174f918e ("virtio: write back F_VERSION_1 before validate")
+Cc: "Halil Pasic" <pasic@linux.ibm.com>
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/virtio/virtio.c | 39 ++++++++++++++++++++++-----------------
+ include/linux/virtio_config.h | 3 ++-
+ 2 files changed, 24 insertions(+), 18 deletions(-)
+
+--- a/drivers/virtio/virtio.c
++++ b/drivers/virtio/virtio.c
+@@ -167,14 +167,13 @@ void virtio_add_status(struct virtio_dev
+ }
+ EXPORT_SYMBOL_GPL(virtio_add_status);
+
+-static int virtio_finalize_features(struct virtio_device *dev)
++/* Do some validation, then set FEATURES_OK */
++static int virtio_features_ok(struct virtio_device *dev)
+ {
+- int ret = dev->config->finalize_features(dev);
+ unsigned status;
++ int ret;
+
+ might_sleep();
+- if (ret)
+- return ret;
+
+ ret = arch_has_restricted_virtio_memory_access();
+ if (ret) {
+@@ -239,17 +238,6 @@ static int virtio_dev_probe(struct devic
+ driver_features_legacy = driver_features;
+ }
+
+- /*
+- * Some devices detect legacy solely via F_VERSION_1. Write
+- * F_VERSION_1 to force LE config space accesses before FEATURES_OK for
+- * these when needed.
+- */
+- if (drv->validate && !virtio_legacy_is_little_endian()
+- && device_features & BIT_ULL(VIRTIO_F_VERSION_1)) {
+- dev->features = BIT_ULL(VIRTIO_F_VERSION_1);
+- dev->config->finalize_features(dev);
+- }
+-
+ if (device_features & (1ULL << VIRTIO_F_VERSION_1))
+ dev->features = driver_features & device_features;
+ else
+@@ -260,13 +248,26 @@ static int virtio_dev_probe(struct devic
+ if (device_features & (1ULL << i))
+ __virtio_set_bit(dev, i);
+
++ err = dev->config->finalize_features(dev);
++ if (err)
++ goto err;
++
+ if (drv->validate) {
++ u64 features = dev->features;
++
+ err = drv->validate(dev);
+ if (err)
+ goto err;
++
++ /* Did validation change any features? Then write them again. */
++ if (features != dev->features) {
++ err = dev->config->finalize_features(dev);
++ if (err)
++ goto err;
++ }
+ }
+
+- err = virtio_finalize_features(dev);
++ err = virtio_features_ok(dev);
+ if (err)
+ goto err;
+
+@@ -437,7 +438,11 @@ int virtio_device_restore(struct virtio_
+ /* We have a driver! */
+ virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);
+
+- ret = virtio_finalize_features(dev);
++ ret = dev->config->finalize_features(dev);
++ if (ret)
++ goto err;
++
++ ret = virtio_features_ok(dev);
+ if (ret)
+ goto err;
+
+--- a/include/linux/virtio_config.h
++++ b/include/linux/virtio_config.h
+@@ -62,8 +62,9 @@ struct virtio_shm_region {
+ * Returns the first 64 feature bits (all we currently need).
+ * @finalize_features: confirm what device features we'll be using.
+ * vdev: the virtio_device
+- * This gives the final feature bits for the device: it can change
++ * This sends the driver feature bits to the device: it can change
+ * the dev->feature bits if it wants.
++ * Note: despite the name this can be called any number of times.
+ * Returns 0 on success or error status
+ * @bus_name: return the bus name associated with the device (optional)
+ * vdev: the virtio_device
--- /dev/null
+From 838d6d3461db0fdbf33fc5f8a69c27b50b4a46da Mon Sep 17 00:00:00 2001
+From: "Michael S. Tsirkin" <mst@redhat.com>
+Date: Fri, 14 Jan 2022 14:56:15 -0500
+Subject: virtio: unexport virtio_finalize_features
+
+From: Michael S. Tsirkin <mst@redhat.com>
+
+commit 838d6d3461db0fdbf33fc5f8a69c27b50b4a46da upstream.
+
+virtio_finalize_features is only used internally within virtio.
+No reason to export it.
+
+Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
+Reviewed-by: Cornelia Huck <cohuck@redhat.com>
+Acked-by: Jason Wang <jasowang@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/virtio/virtio.c | 3 +--
+ include/linux/virtio.h | 1 -
+ 2 files changed, 1 insertion(+), 3 deletions(-)
+
+--- a/drivers/virtio/virtio.c
++++ b/drivers/virtio/virtio.c
+@@ -167,7 +167,7 @@ void virtio_add_status(struct virtio_dev
+ }
+ EXPORT_SYMBOL_GPL(virtio_add_status);
+
+-int virtio_finalize_features(struct virtio_device *dev)
++static int virtio_finalize_features(struct virtio_device *dev)
+ {
+ int ret = dev->config->finalize_features(dev);
+ unsigned status;
+@@ -203,7 +203,6 @@ int virtio_finalize_features(struct virt
+ }
+ return 0;
+ }
+-EXPORT_SYMBOL_GPL(virtio_finalize_features);
+
+ static int virtio_dev_probe(struct device *_d)
+ {
+--- a/include/linux/virtio.h
++++ b/include/linux/virtio.h
+@@ -135,7 +135,6 @@ void virtio_break_device(struct virtio_d
+ void virtio_config_changed(struct virtio_device *dev);
+ void virtio_config_disable(struct virtio_device *dev);
+ void virtio_config_enable(struct virtio_device *dev);
+-int virtio_finalize_features(struct virtio_device *dev);
+ #ifdef CONFIG_PM_SLEEP
+ int virtio_device_freeze(struct virtio_device *dev);
+ int virtio_device_restore(struct virtio_device *dev);
--- /dev/null
+From c993ee0f9f81caf5767a50d1faeba39a0dc82af2 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:23:31 +0000
+Subject: watch_queue: Fix filter limit check
+
+From: David Howells <dhowells@redhat.com>
+
+commit c993ee0f9f81caf5767a50d1faeba39a0dc82af2 upstream.
+
+In watch_queue_set_filter(), there are a couple of places where we check
+that the filter type value does not exceed what the type_filter bitmap
+can hold. One place calculates the number of bits by:
+
+ if (tf[i].type >= sizeof(wfilter->type_filter) * 8)
+
+which is fine, but the second does:
+
+ if (tf[i].type >= sizeof(wfilter->type_filter) * BITS_PER_LONG)
+
+which is not. This can lead to a couple of out-of-bounds writes due to
+a too-large type:
+
+ (1) __set_bit() on wfilter->type_filter
+ (2) Writing more elements in wfilter->filters[] than we allocated.
+
+Fix this by just using the proper WATCH_TYPE__NR instead, which is the
+number of types we actually know about.
+
+The bug may cause an oops looking something like:
+
+ BUG: KASAN: slab-out-of-bounds in watch_queue_set_filter+0x659/0x740
+ Write of size 4 at addr ffff88800d2c66bc by task watch_queue_oob/611
+ ...
+ Call Trace:
+ <TASK>
+ dump_stack_lvl+0x45/0x59
+ print_address_description.constprop.0+0x1f/0x150
+ ...
+ kasan_report.cold+0x7f/0x11b
+ ...
+ watch_queue_set_filter+0x659/0x740
+ ...
+ __x64_sys_ioctl+0x127/0x190
+ do_syscall_64+0x43/0x90
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+
+ Allocated by task 611:
+ kasan_save_stack+0x1e/0x40
+ __kasan_kmalloc+0x81/0xa0
+ watch_queue_set_filter+0x23a/0x740
+ __x64_sys_ioctl+0x127/0x190
+ do_syscall_64+0x43/0x90
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+
+ The buggy address belongs to the object at ffff88800d2c66a0
+ which belongs to the cache kmalloc-32 of size 32
+ The buggy address is located 28 bytes inside of
+ 32-byte region [ffff88800d2c66a0, ffff88800d2c66c0)
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/watch_queue.h | 3 ++-
+ kernel/watch_queue.c | 4 ++--
+ 2 files changed, 4 insertions(+), 3 deletions(-)
+
+--- a/include/linux/watch_queue.h
++++ b/include/linux/watch_queue.h
+@@ -28,7 +28,8 @@ struct watch_type_filter {
+ struct watch_filter {
+ union {
+ struct rcu_head rcu;
+- unsigned long type_filter[2]; /* Bitmask of accepted types */
++ /* Bitmask of accepted types */
++ DECLARE_BITMAP(type_filter, WATCH_TYPE__NR);
+ };
+ u32 nr_filters; /* Number of filters */
+ struct watch_type_filter filters[];
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -320,7 +320,7 @@ long watch_queue_set_filter(struct pipe_
+ tf[i].info_mask & WATCH_INFO_LENGTH)
+ goto err_filter;
+ /* Ignore any unknown types */
+- if (tf[i].type >= sizeof(wfilter->type_filter) * 8)
++ if (tf[i].type >= WATCH_TYPE__NR)
+ continue;
+ nr_filter++;
+ }
+@@ -336,7 +336,7 @@ long watch_queue_set_filter(struct pipe_
+
+ q = wfilter->filters;
+ for (i = 0; i < filter.nr_filters; i++) {
+- if (tf[i].type >= sizeof(wfilter->type_filter) * BITS_PER_LONG)
++ if (tf[i].type >= WATCH_TYPE__NR)
+ continue;
+
+ q->type = tf[i].type;
--- /dev/null
+From 2ed147f015af2b48f41c6f0b6746aa9ea85c19f3 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:24:36 +0000
+Subject: watch_queue: Fix lack of barrier/sync/lock between post and read
+
+From: David Howells <dhowells@redhat.com>
+
+commit 2ed147f015af2b48f41c6f0b6746aa9ea85c19f3 upstream.
+
+There's nothing to synchronise post_one_notification() versus
+pipe_read(). Whilst posting is done under pipe->rd_wait.lock, the
+reader only takes pipe->mutex which cannot bar notification posting as
+that may need to be made from contexts that cannot sleep.
+
+Fix this by setting pipe->head with a barrier in post_one_notification()
+and reading pipe->head with a barrier in pipe_read().
+
+If that's not sufficient, the rd_wait.lock will need to be taken,
+possibly in a ->confirm() op so that it only applies to notifications.
+The lock would, however, have to be dropped before copy_page_to_iter()
+is invoked.
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/pipe.c | 3 ++-
+ kernel/watch_queue.c | 2 +-
+ 2 files changed, 3 insertions(+), 2 deletions(-)
+
+--- a/fs/pipe.c
++++ b/fs/pipe.c
+@@ -252,7 +252,8 @@ pipe_read(struct kiocb *iocb, struct iov
+ */
+ was_full = pipe_full(pipe->head, pipe->tail, pipe->max_usage);
+ for (;;) {
+- unsigned int head = pipe->head;
++ /* Read ->head with a barrier vs post_one_notification() */
++ unsigned int head = smp_load_acquire(&pipe->head);
+ unsigned int tail = pipe->tail;
+ unsigned int mask = pipe->ring_size - 1;
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -113,7 +113,7 @@ static bool post_one_notification(struct
+ buf->offset = offset;
+ buf->len = len;
+ buf->flags = PIPE_BUF_FLAG_WHOLE;
+- pipe->head = head + 1;
++ smp_store_release(&pipe->head, head + 1); /* vs pipe_read() */
+
+ if (!test_and_clear_bit(note, wqueue->notes_bitmap)) {
+ spin_unlock_irq(&pipe->rd_wait.lock);
--- /dev/null
+From 3b4c0371928c17af03e8397ac842346624017ce6 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:24:22 +0000
+Subject: watch_queue: Fix the alloc bitmap size to reflect notes allocated
+
+From: David Howells <dhowells@redhat.com>
+
+commit 3b4c0371928c17af03e8397ac842346624017ce6 upstream.
+
+Currently, watch_queue_set_size() sets the number of notes available in
+wqueue->nr_notes according to the number of notes allocated, but sets
+the size of the bitmap to the unrounded number of notes originally asked
+for.
+
+Fix this by setting the bitmap size to the number of notes we're
+actually going to make available (ie. the number allocated).
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/watch_queue.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -244,6 +244,7 @@ long watch_queue_set_size(struct pipe_in
+ goto error;
+ }
+
++ nr_notes = nr_pages * WATCH_QUEUE_NOTES_PER_PAGE;
+ ret = pipe_resize_ring(pipe, roundup_pow_of_two(nr_notes));
+ if (ret < 0)
+ goto error;
+@@ -269,7 +270,7 @@ long watch_queue_set_size(struct pipe_in
+ wqueue->notes = pages;
+ wqueue->notes_bitmap = bitmap;
+ wqueue->nr_pages = nr_pages;
+- wqueue->nr_notes = nr_pages * WATCH_QUEUE_NOTES_PER_PAGE;
++ wqueue->nr_notes = nr_notes;
+ return 0;
+
+ error_p:
--- /dev/null
+From 96a4d8912b28451cd62825fd7caa0e66e091d938 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:24:08 +0000
+Subject: watch_queue: Fix to always request a pow-of-2 pipe ring size
+
+From: David Howells <dhowells@redhat.com>
+
+commit 96a4d8912b28451cd62825fd7caa0e66e091d938 upstream.
+
+The pipe ring size must always be a power of 2 as the head and tail
+pointers are masked off by AND'ing with the size of the ring - 1.
+watch_queue_set_size(), however, lets you specify any number of notes
+between 1 and 511. This number is passed through to pipe_resize_ring()
+without checking/forcing its alignment.
+
+Fix this by rounding the number of slots required up to the nearest
+power of two. The request is meant to guarantee that at least that many
+notifications can be generated before the queue is full, so rounding
+down isn't an option, but, alternatively, it may be better to give an
+error if we aren't allowed to allocate that much ring space.
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/watch_queue.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -244,7 +244,7 @@ long watch_queue_set_size(struct pipe_in
+ goto error;
+ }
+
+- ret = pipe_resize_ring(pipe, nr_notes);
++ ret = pipe_resize_ring(pipe, roundup_pow_of_two(nr_notes));
+ if (ret < 0)
+ goto error;
+
--- /dev/null
+From c1853fbadcba1497f4907971e7107888e0714c81 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:23:46 +0000
+Subject: watch_queue: Fix to release page in ->release()
+
+From: David Howells <dhowells@redhat.com>
+
+commit c1853fbadcba1497f4907971e7107888e0714c81 upstream.
+
+When a pipe ring descriptor points to a notification message, the
+refcount on the backing page is incremented by the generic get function,
+but the release function, which marks the bitmap, doesn't drop the page
+ref.
+
+Fix this by calling generic_pipe_buf_release() at the end of
+watch_queue_pipe_buf_release().
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/watch_queue.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -54,6 +54,7 @@ static void watch_queue_pipe_buf_release
+ bit += page->index;
+
+ set_bit(bit, wqueue->notes_bitmap);
++ generic_pipe_buf_release(pipe, buf);
+ }
+
+ // No try_steal function => no stealing
--- /dev/null
+From 7ea1a0124b6da246b5bc8c66cddaafd36acf3ecb Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:24:29 +0000
+Subject: watch_queue: Free the alloc bitmap when the watch_queue is torn down
+
+From: David Howells <dhowells@redhat.com>
+
+commit 7ea1a0124b6da246b5bc8c66cddaafd36acf3ecb upstream.
+
+Free the watch_queue note allocation bitmap when the watch_queue is
+destroyed.
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/watch_queue.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -373,6 +373,7 @@ static void __put_watch_queue(struct kre
+
+ for (i = 0; i < wqueue->nr_pages; i++)
+ __free_page(wqueue->notes[i]);
++ bitmap_free(wqueue->notes_bitmap);
+
+ wfilter = rcu_access_pointer(wqueue->filter);
+ if (wfilter)
--- /dev/null
+From 4edc0760412b0c4ecefc7e02cb855b310b122825 Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:24:47 +0000
+Subject: watch_queue: Make comment about setting ->defunct more accurate
+
+From: David Howells <dhowells@redhat.com>
+
+commit 4edc0760412b0c4ecefc7e02cb855b310b122825 upstream.
+
+watch_queue_clear() has a comment stating that setting ->defunct to true
+preventing new additions as well as preventing notifications. Whilst
+the latter is true, the first bit is superfluous since at the time this
+function is called, the pipe cannot be accessed to add new event
+sources.
+
+Remove the "new additions" bit from the comment.
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/watch_queue.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/kernel/watch_queue.c
++++ b/kernel/watch_queue.c
+@@ -569,7 +569,7 @@ void watch_queue_clear(struct watch_queu
+ rcu_read_lock();
+ spin_lock_bh(&wqueue->lock);
+
+- /* Prevent new additions and prevent notifications from happening */
++ /* Prevent new notifications from being stored. */
+ wqueue->defunct = true;
+
+ while (!hlist_empty(&wqueue->watches)) {
--- /dev/null
+From db8facfc9fafacefe8a835416a6b77c838088f8b Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Fri, 11 Mar 2022 13:23:38 +0000
+Subject: watch_queue, pipe: Free watchqueue state after clearing pipe ring
+
+From: David Howells <dhowells@redhat.com>
+
+commit db8facfc9fafacefe8a835416a6b77c838088f8b upstream.
+
+In free_pipe_info(), free the watchqueue state after clearing the pipe
+ring as each pipe ring descriptor has a release function, and in the
+case of a notification message, this is watch_queue_pipe_buf_release()
+which tries to mark the allocation bitmap that was previously released.
+
+Fix this by moving the put of the pipe's ref on the watch queue to after
+the ring has been cleared. We still need to call watch_queue_clear()
+before doing that to make sure that the pipe is disconnected from any
+notification sources first.
+
+Fixes: c73be61cede5 ("pipe: Add general notification queue support")
+Reported-by: Jann Horn <jannh@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/pipe.c | 8 +++++---
+ 1 file changed, 5 insertions(+), 3 deletions(-)
+
+--- a/fs/pipe.c
++++ b/fs/pipe.c
+@@ -830,10 +830,8 @@ void free_pipe_info(struct pipe_inode_in
+ int i;
+
+ #ifdef CONFIG_WATCH_QUEUE
+- if (pipe->watch_queue) {
++ if (pipe->watch_queue)
+ watch_queue_clear(pipe->watch_queue);
+- put_watch_queue(pipe->watch_queue);
+- }
+ #endif
+
+ (void) account_pipe_buffers(pipe->user, pipe->nr_accounted, 0);
+@@ -843,6 +841,10 @@ void free_pipe_info(struct pipe_inode_in
+ if (buf->ops)
+ pipe_buf_release(pipe, buf);
+ }
++#ifdef CONFIG_WATCH_QUEUE
++ if (pipe->watch_queue)
++ put_watch_queue(pipe->watch_queue);
++#endif
+ if (pipe->tmp_page)
+ __free_page(pipe->tmp_page);
+ kfree(pipe->bufs);
projects / thirdparty / kernel / stable-queue.git / commitdiff
