Pentium 4's which are INTEL_P4_PRESCOTT (model 0x03) and later have
a constant TSC. This was correctly captured until commit fadb6f569b10
("x86/cpu/intel: Limit the non-architectural constant_tsc model checks").
In that commit, an error was introduced while selecting the last P4
model (0x06) as the upper bound. Model 0x06 was transposed to
INTEL_P4_WILLAMETTE, which is just plain wrong. That was presumably a
simple typo, probably just copying and pasting the wrong P4 model.
Fix the constant TSC logic to cover all later P4 models. End at
INTEL_P4_CEDARMILL which accurately corresponds to the last P4 model.
Fixes: fadb6f569b10 ("x86/cpu/intel: Limit the non-architectural constant_tsc model checks")
Cc: <stable(a)vger.kernel.org> # v6.15
Reviewed-by: Sohil Mehta <sohil.mehta(a)intel.com>
Signed-off-by: Suchit Karunakaran <suchitkarunakaran(a)gmail.com>
---
Changes since v4:
- Updated the patch based on review suggestions
Changes since v3:
- Refined changelog
Changes since v2:
- Improved commit message
Changes since v1:
- Fixed incorrect logic
arch/x86/kernel/cpu/intel.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 076eaa41b8c8..98ae4c37c93e 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -262,7 +262,7 @@ static void early_init_intel(struct cpuinfo_x86 *c)
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
- } else if ((c->x86_vfm >= INTEL_P4_PRESCOTT && c->x86_vfm <= INTEL_P4_WILLAMETTE) ||
+ } else if ((c->x86_vfm >= INTEL_P4_PRESCOTT && c->x86_vfm <= INTEL_P4_CEDARMILL) ||
(c->x86_vfm >= INTEL_CORE_YONAH && c->x86_vfm <= INTEL_IVYBRIDGE)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
}
--
2.50.1
Dear stable team,
I'd like to have the following commit backported to v6.16 and v6.15:
e40fc1160d49 ("mfd: cros_ec: Separate charge-control probing from USB-PD")
It fixes probing issues for the cros-charge-control driver, for details
see the commit message.
As far as I can see, the commit also was marked for -stable backporting
from the beginning. Somehow this doesn't seem to have worked.
Thanks for your consideration,
Thomas
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081509-uncrown-janitor-adad@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas(a)wunner.de>
Date: Sun, 13 Jul 2025 16:31:01 +0200
Subject: [PATCH] PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable
ports
pci_bridge_d3_possible() is called from both pcie_portdrv_probe() and
pcie_portdrv_remove() to determine whether runtime power management shall
be enabled (on probe) or disabled (on remove) on a PCIe port.
The underlying assumption is that pci_bridge_d3_possible() always returns
the same value, else a runtime PM reference imbalance would occur. That
assumption is not given if the PCIe port is inaccessible on remove due to
hot-unplug: pci_bridge_d3_possible() calls pciehp_is_native(), which
accesses Config Space to determine whether the port is Hot-Plug Capable.
An inaccessible port returns "all ones", which is converted to "all
zeroes" by pcie_capability_read_dword(). Hence the port no longer seems
Hot-Plug Capable on remove even though it was on probe.
The resulting runtime PM ref imbalance causes warning messages such as:
pcieport 0000:02:04.0: Runtime PM usage count underflow!
Avoid the Config Space access (and thus the runtime PM ref imbalance) by
caching the Hot-Plug Capable bit in struct pci_dev.
The struct already contains an "is_hotplug_bridge" flag, which however is
not only set on Hot-Plug Capable PCIe ports, but also Conventional PCI
Hot-Plug bridges and ACPI slots. The flag identifies bridges which are
allocated additional MMIO and bus number resources to allow for hierarchy
expansion.
The kernel is somewhat sloppily using "is_hotplug_bridge" in a number of
places to identify Hot-Plug Capable PCIe ports, even though the flag
encompasses other devices. Subsequent commits replace these occurrences
with the new flag to clearly delineate Hot-Plug Capable PCIe ports from
other kinds of hotplug bridges.
Document the existing "is_hotplug_bridge" and the new "is_pciehp" flag
and document the (non-obvious) requirement that pci_bridge_d3_possible()
always returns the same value across the entire lifetime of a bridge,
including its hot-removal.
Fixes: 5352a44a561d ("PCI: pciehp: Make pciehp_is_native() stricter")
Reported-by: Laurent Bigonville <bigon(a)bigon.be>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220216
Reported-by: Mario Limonciello <mario.limonciello(a)amd.com>
Closes: https://lore.kernel.org/r/20250609020223.269407-3-superm1@kernel.org/
Link: https://lore.kernel.org/all/20250620025535.3425049-3-superm1@kernel.org/T/#u
Signed-off-by: Lukas Wunner <lukas(a)wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
Acked-by: Rafael J. Wysocki <rafael(a)kernel.org>
Cc: stable(a)vger.kernel.org # v4.18+
Link: https://patch.msgid.link/fe5dcc3b2e62ee1df7905d746bde161eb1b3291c.175239010…
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index b78e0e417324..efe478e5073e 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -816,13 +816,11 @@ int pci_acpi_program_hp_params(struct pci_dev *dev)
bool pciehp_is_native(struct pci_dev *bridge)
{
const struct pci_host_bridge *host;
- u32 slot_cap;
if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
return false;
- pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
- if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
+ if (!bridge->is_pciehp)
return false;
if (pcie_ports_native)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e9448d55113b..23d8fe98ddf9 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3030,8 +3030,12 @@ static const struct dmi_system_id bridge_d3_blacklist[] = {
* pci_bridge_d3_possible - Is it possible to put the bridge into D3
* @bridge: Bridge to check
*
- * This function checks if it is possible to move the bridge to D3.
* Currently we only allow D3 for some PCIe ports and for Thunderbolt.
+ *
+ * Return: Whether it is possible to move the bridge to D3.
+ *
+ * The return value is guaranteed to be constant across the entire lifetime
+ * of the bridge, including its hot-removal.
*/
bool pci_bridge_d3_possible(struct pci_dev *bridge)
{
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 4b8693ec9e4c..cf50be63bf5f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1678,7 +1678,7 @@ void set_pcie_hotplug_bridge(struct pci_dev *pdev)
pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
if (reg32 & PCI_EXP_SLTCAP_HPC)
- pdev->is_hotplug_bridge = 1;
+ pdev->is_hotplug_bridge = pdev->is_pciehp = 1;
}
static void set_pcie_thunderbolt(struct pci_dev *dev)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 05e68f35f392..d56d0dd80afb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -328,6 +328,11 @@ struct rcec_ea;
* determined (e.g., for Root Complex Integrated
* Endpoints without the relevant Capability
* Registers).
+ * @is_hotplug_bridge: Hotplug bridge of any kind (e.g. PCIe Hot-Plug Capable,
+ * Conventional PCI Hot-Plug, ACPI slot).
+ * Such bridges are allocated additional MMIO and bus
+ * number resources to allow for hierarchy expansion.
+ * @is_pciehp: PCIe Hot-Plug Capable bridge.
*/
struct pci_dev {
struct list_head bus_list; /* Node in per-bus list */
@@ -451,6 +456,7 @@ struct pci_dev {
unsigned int is_physfn:1;
unsigned int is_virtfn:1;
unsigned int is_hotplug_bridge:1;
+ unsigned int is_pciehp:1;
unsigned int shpc_managed:1; /* SHPC owned by shpchp */
unsigned int is_thunderbolt:1; /* Thunderbolt controller */
/*
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 3f66ccbaaef3a0c5bd844eab04e3207b4061c546
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081543-myself-easiest-be00@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3f66ccbaaef3a0c5bd844eab04e3207b4061c546 Mon Sep 17 00:00:00 2001
From: Damien Le Moal <dlemoal(a)kernel.org>
Date: Wed, 25 Jun 2025 18:33:23 +0900
Subject: [PATCH] block: Make REQ_OP_ZONE_FINISH a write operation
REQ_OP_ZONE_FINISH is defined as "12", which makes
op_is_write(REQ_OP_ZONE_FINISH) return false, despite the fact that a
zone finish operation is an operation that modifies a zone (transition
it to full) and so should be considered as a write operation (albeit
one that does not transfer any data to the device).
Fix this by redefining REQ_OP_ZONE_FINISH to be an odd number (13), and
redefine REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL using sequential
odd numbers from that new value.
Fixes: 6c1b1da58f8c ("block: add zone open, close and finish operations")
Cc: stable(a)vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal(a)kernel.org>
Reviewed-by: Bart Van Assche <bvanassche(a)acm.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn(a)wdc.com>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Link: https://lore.kernel.org/r/20250625093327.548866-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 3d1577f07c1c..930daff207df 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -350,11 +350,11 @@ enum req_op {
/* Close a zone */
REQ_OP_ZONE_CLOSE = (__force blk_opf_t)11,
/* Transition a zone to full */
- REQ_OP_ZONE_FINISH = (__force blk_opf_t)12,
+ REQ_OP_ZONE_FINISH = (__force blk_opf_t)13,
/* reset a zone write pointer */
- REQ_OP_ZONE_RESET = (__force blk_opf_t)13,
+ REQ_OP_ZONE_RESET = (__force blk_opf_t)15,
/* reset all the zone present on the device */
- REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)15,
+ REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)17,
/* Driver private requests */
REQ_OP_DRV_IN = (__force blk_opf_t)34,
Hello,
Status summary for stable/linux-6.6.y
Dashboard:
https://d.kernelci.org/c/stable/linux-6.6.y/bb9c90ab9c5a1a933a0dfd302a3fde7…
giturl: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
branch: linux-6.6.y
commit hash: bb9c90ab9c5a1a933a0dfd302a3fde73642b2b06
origin: maestro
test start time: 2025-08-15 10:52:19.705000+00:00
Builds: 45 ✅ 0 ❌ 0 ⚠️
Boots: 60 ✅ 0 ❌ 42 ⚠️
Tests: 3948 ✅ 607 ❌ 1617 ⚠️
### POSSIBLE REGRESSIONS
No possible regressions observed.
### FIXED REGRESSIONS
No fixed regressions observed.
### UNSTABLE TESTS
Hardware: bcm2711-rpi-4-b
- boot (defconfig+lab-setup+kselftest)
last run: https://d.kernelci.org/test/maestro:689f184b233e484a3f986be3
history: > ✅ > ✅ > ⚠️
Hardware: dell-latitude-3445-7520c-skyrim
- boot (cros://chromeos-6.6/x86_64/chromeos-amd-stoneyridge.flavour.config+lab-setup+x86-board+CONFIG_MODULE_COMPRESS=n+CONFIG_MODULE_COMPRESS_NONE=y)
last run: https://d.kernelci.org/test/maestro:689f24dd233e484a3f98e2c2
history: > ⚠️ > ⚠️
Sent every day if there were changes in the past 24 hours.
Legend: ✅ PASS ❌ FAIL ⚠️ INCONCLUSIVE
--
This is an experimental report format. Please send feedback in!
Talk to us at kernelci(a)lists.linux.dev
Made with love by the KernelCI team - https://kernelci.org
Hello,
Status summary for stable/linux-6.1.y
Dashboard:
https://d.kernelci.org/c/stable/linux-6.1.y/0bc96de781b4da716c8dbd248af4b26…
giturl: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
branch: linux-6.1.y
commit hash: 0bc96de781b4da716c8dbd248af4b26d8d8341f5
origin: maestro
test start time: 2025-08-15 10:52:19.284000+00:00
Builds: 44 ✅ 1 ❌ 0 ⚠️
Boots: 35 ✅ 0 ❌ 24 ⚠️
Tests: 1994 ✅ 166 ❌ 1054 ⚠️
### POSSIBLE REGRESSIONS
No possible regressions observed.
### FIXED REGRESSIONS
No fixed regressions observed.
### UNSTABLE TESTS
Hardware: bcm2711-rpi-4-b
- boot (defconfig+lab-setup+kselftest)
last run: https://d.kernelci.org/test/maestro:689f28a2233e484a3f98e9a8
history: > ✅ > ✅ > ⚠️
Sent every day if there were changes in the past 24 hours.
Legend: ✅ PASS ❌ FAIL ⚠️ INCONCLUSIVE
--
This is an experimental report format. Please send feedback in!
Talk to us at kernelci(a)lists.linux.dev
Made with love by the KernelCI team - https://kernelci.org
Using device_find_child() and of_find_device_by_node() to locate
devices could cause an imbalance in the device's reference count.
device_find_child() and of_find_device_by_node() both call
get_device() to increment the reference count of the found device
before returning the pointer. In mtk_drm_get_all_drm_priv(), these
references are never released through put_device(), resulting in
permanent reference count increments. Additionally, the
for_each_child_of_node() iterator fails to release node references in
all code paths. This leaks device node references when loop
termination occurs before reaching MAX_CRTC. These reference count
leaks may prevent device/node resources from being properly released
during driver unbind operations.
As comment of device_find_child() says, 'NOTE: you will need to drop
the reference with put_device() after use'.
Found by code review.
Cc: stable(a)vger.kernel.org
Fixes: 1ef7ed48356c ("drm/mediatek: Modify mediatek-drm for mt8195 multi mmsys support")
Signed-off-by: Ma Ke <make24(a)iscas.ac.cn>
---
Changes in v2:
- added goto labels as suggestions.
---
drivers/gpu/drm/mediatek/mtk_drm_drv.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index d5e6bab36414..f8a817689e16 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -387,19 +387,19 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev)
of_id = of_match_node(mtk_drm_of_ids, node);
if (!of_id)
- continue;
+ goto next_put_node;
pdev = of_find_device_by_node(node);
if (!pdev)
- continue;
+ goto next_put_node;
drm_dev = device_find_child(&pdev->dev, NULL, mtk_drm_match);
if (!drm_dev)
- continue;
+ goto next_put_device_pdev_dev;
temp_drm_priv = dev_get_drvdata(drm_dev);
if (!temp_drm_priv)
- continue;
+ goto next_put_device_drm_dev;
if (temp_drm_priv->data->main_len)
all_drm_priv[CRTC_MAIN] = temp_drm_priv;
@@ -411,10 +411,17 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev)
if (temp_drm_priv->mtk_drm_bound)
cnt++;
- if (cnt == MAX_CRTC) {
- of_node_put(node);
+next_put_device_drm_dev:
+ put_device(drm_dev);
+
+next_put_device_pdev_dev:
+ put_device(&pdev->dev);
+
+next_put_node:
+ of_node_put(node);
+
+ if (cnt == MAX_CRTC)
break;
- }
}
if (drm_priv->data->mmsys_dev_num == cnt) {
--
2.25.1
The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081508-ultra-derived-f72d@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6cff20ce3b92ffbf2fc5eb9e5a030b3672aa414a Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas(a)wunner.de>
Date: Sun, 13 Jul 2025 16:31:01 +0200
Subject: [PATCH] PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable
ports
pci_bridge_d3_possible() is called from both pcie_portdrv_probe() and
pcie_portdrv_remove() to determine whether runtime power management shall
be enabled (on probe) or disabled (on remove) on a PCIe port.
The underlying assumption is that pci_bridge_d3_possible() always returns
the same value, else a runtime PM reference imbalance would occur. That
assumption is not given if the PCIe port is inaccessible on remove due to
hot-unplug: pci_bridge_d3_possible() calls pciehp_is_native(), which
accesses Config Space to determine whether the port is Hot-Plug Capable.
An inaccessible port returns "all ones", which is converted to "all
zeroes" by pcie_capability_read_dword(). Hence the port no longer seems
Hot-Plug Capable on remove even though it was on probe.
The resulting runtime PM ref imbalance causes warning messages such as:
pcieport 0000:02:04.0: Runtime PM usage count underflow!
Avoid the Config Space access (and thus the runtime PM ref imbalance) by
caching the Hot-Plug Capable bit in struct pci_dev.
The struct already contains an "is_hotplug_bridge" flag, which however is
not only set on Hot-Plug Capable PCIe ports, but also Conventional PCI
Hot-Plug bridges and ACPI slots. The flag identifies bridges which are
allocated additional MMIO and bus number resources to allow for hierarchy
expansion.
The kernel is somewhat sloppily using "is_hotplug_bridge" in a number of
places to identify Hot-Plug Capable PCIe ports, even though the flag
encompasses other devices. Subsequent commits replace these occurrences
with the new flag to clearly delineate Hot-Plug Capable PCIe ports from
other kinds of hotplug bridges.
Document the existing "is_hotplug_bridge" and the new "is_pciehp" flag
and document the (non-obvious) requirement that pci_bridge_d3_possible()
always returns the same value across the entire lifetime of a bridge,
including its hot-removal.
Fixes: 5352a44a561d ("PCI: pciehp: Make pciehp_is_native() stricter")
Reported-by: Laurent Bigonville <bigon(a)bigon.be>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220216
Reported-by: Mario Limonciello <mario.limonciello(a)amd.com>
Closes: https://lore.kernel.org/r/20250609020223.269407-3-superm1@kernel.org/
Link: https://lore.kernel.org/all/20250620025535.3425049-3-superm1@kernel.org/T/#u
Signed-off-by: Lukas Wunner <lukas(a)wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
Acked-by: Rafael J. Wysocki <rafael(a)kernel.org>
Cc: stable(a)vger.kernel.org # v4.18+
Link: https://patch.msgid.link/fe5dcc3b2e62ee1df7905d746bde161eb1b3291c.175239010…
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index b78e0e417324..efe478e5073e 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -816,13 +816,11 @@ int pci_acpi_program_hp_params(struct pci_dev *dev)
bool pciehp_is_native(struct pci_dev *bridge)
{
const struct pci_host_bridge *host;
- u32 slot_cap;
if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
return false;
- pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
- if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
+ if (!bridge->is_pciehp)
return false;
if (pcie_ports_native)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e9448d55113b..23d8fe98ddf9 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3030,8 +3030,12 @@ static const struct dmi_system_id bridge_d3_blacklist[] = {
* pci_bridge_d3_possible - Is it possible to put the bridge into D3
* @bridge: Bridge to check
*
- * This function checks if it is possible to move the bridge to D3.
* Currently we only allow D3 for some PCIe ports and for Thunderbolt.
+ *
+ * Return: Whether it is possible to move the bridge to D3.
+ *
+ * The return value is guaranteed to be constant across the entire lifetime
+ * of the bridge, including its hot-removal.
*/
bool pci_bridge_d3_possible(struct pci_dev *bridge)
{
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 4b8693ec9e4c..cf50be63bf5f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1678,7 +1678,7 @@ void set_pcie_hotplug_bridge(struct pci_dev *pdev)
pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
if (reg32 & PCI_EXP_SLTCAP_HPC)
- pdev->is_hotplug_bridge = 1;
+ pdev->is_hotplug_bridge = pdev->is_pciehp = 1;
}
static void set_pcie_thunderbolt(struct pci_dev *dev)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 05e68f35f392..d56d0dd80afb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -328,6 +328,11 @@ struct rcec_ea;
* determined (e.g., for Root Complex Integrated
* Endpoints without the relevant Capability
* Registers).
+ * @is_hotplug_bridge: Hotplug bridge of any kind (e.g. PCIe Hot-Plug Capable,
+ * Conventional PCI Hot-Plug, ACPI slot).
+ * Such bridges are allocated additional MMIO and bus
+ * number resources to allow for hierarchy expansion.
+ * @is_pciehp: PCIe Hot-Plug Capable bridge.
*/
struct pci_dev {
struct list_head bus_list; /* Node in per-bus list */
@@ -451,6 +456,7 @@ struct pci_dev {
unsigned int is_physfn:1;
unsigned int is_virtfn:1;
unsigned int is_hotplug_bridge:1;
+ unsigned int is_pciehp:1;
unsigned int shpc_managed:1; /* SHPC owned by shpchp */
unsigned int is_thunderbolt:1; /* Thunderbolt controller */
/*
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 3f66ccbaaef3a0c5bd844eab04e3207b4061c546
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081543-graffiti-nastily-6e2b@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3f66ccbaaef3a0c5bd844eab04e3207b4061c546 Mon Sep 17 00:00:00 2001
From: Damien Le Moal <dlemoal(a)kernel.org>
Date: Wed, 25 Jun 2025 18:33:23 +0900
Subject: [PATCH] block: Make REQ_OP_ZONE_FINISH a write operation
REQ_OP_ZONE_FINISH is defined as "12", which makes
op_is_write(REQ_OP_ZONE_FINISH) return false, despite the fact that a
zone finish operation is an operation that modifies a zone (transition
it to full) and so should be considered as a write operation (albeit
one that does not transfer any data to the device).
Fix this by redefining REQ_OP_ZONE_FINISH to be an odd number (13), and
redefine REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL using sequential
odd numbers from that new value.
Fixes: 6c1b1da58f8c ("block: add zone open, close and finish operations")
Cc: stable(a)vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal(a)kernel.org>
Reviewed-by: Bart Van Assche <bvanassche(a)acm.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn(a)wdc.com>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Link: https://lore.kernel.org/r/20250625093327.548866-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 3d1577f07c1c..930daff207df 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -350,11 +350,11 @@ enum req_op {
/* Close a zone */
REQ_OP_ZONE_CLOSE = (__force blk_opf_t)11,
/* Transition a zone to full */
- REQ_OP_ZONE_FINISH = (__force blk_opf_t)12,
+ REQ_OP_ZONE_FINISH = (__force blk_opf_t)13,
/* reset a zone write pointer */
- REQ_OP_ZONE_RESET = (__force blk_opf_t)13,
+ REQ_OP_ZONE_RESET = (__force blk_opf_t)15,
/* reset all the zone present on the device */
- REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)15,
+ REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)17,
/* Driver private requests */
REQ_OP_DRV_IN = (__force blk_opf_t)34,
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x b41c1d8d07906786c60893980d52688f31d114a6
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081514-salad-crumpet-f125@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b41c1d8d07906786c60893980d52688f31d114a6 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers(a)kernel.org>
Date: Fri, 4 Jul 2025 00:03:22 -0700
Subject: [PATCH] fscrypt: Don't use problematic non-inline crypto engines
Make fscrypt no longer use Crypto API drivers for non-inline crypto
engines, even when the Crypto API prioritizes them over CPU-based code
(which unfortunately it often does). These drivers tend to be really
problematic, especially for fscrypt's workload. This commit has no
effect on inline crypto engines, which are different and do work well.
Specifically, exclude drivers that have CRYPTO_ALG_KERN_DRIVER_ONLY or
CRYPTO_ALG_ALLOCATES_MEMORY set. (Later, CRYPTO_ALG_ASYNC should be
excluded too. That's omitted for now to keep this commit backportable,
since until recently some CPU-based code had CRYPTO_ALG_ASYNC set.)
There are two major issues with these drivers: bugs and performance.
First, these drivers tend to be buggy. They're fundamentally much more
error-prone and harder to test than the CPU-based code. They often
don't get tested before kernel releases, and even if they do, the crypto
self-tests don't properly test these drivers. Released drivers have
en/decrypted or hashed data incorrectly. These bugs cause issues for
fscrypt users who often didn't even want to use these drivers, e.g.:
- https://github.com/google/fscryptctl/issues/32
- https://github.com/google/fscryptctl/issues/9
- https://lore.kernel.org/r/PH0PR02MB731916ECDB6C613665863B6CFFAA2@PH0PR02MB7…
These drivers have also similarly caused issues for dm-crypt users,
including data corruption and deadlocks. Since Linux v5.10, dm-crypt
has disabled most of them by excluding CRYPTO_ALG_ALLOCATES_MEMORY.
Second, these drivers tend to be *much* slower than the CPU-based code.
This may seem counterintuitive, but benchmarks clearly show it. There's
a *lot* of overhead associated with going to a hardware driver, off the
CPU, and back again. To prove this, I gathered as many systems with
this type of crypto engine as I could, and I measured synchronous
encryption of 4096-byte messages (which matches fscrypt's workload):
Intel Emerald Rapids server:
AES-256-XTS:
xts-aes-vaes-avx512 16171 MB/s [CPU-based, Vector AES]
qat_aes_xts 289 MB/s [Offload, Intel QuickAssist]
Qualcomm SM8650 HDK:
AES-256-XTS:
xts-aes-ce 4301 MB/s [CPU-based, ARMv8 Crypto Extensions]
xts-aes-qce 73 MB/s [Offload, Qualcomm Crypto Engine]
i.MX 8M Nano LPDDR4 EVK:
AES-256-XTS:
xts-aes-ce 647 MB/s [CPU-based, ARMv8 Crypto Extensions]
xts(ecb-aes-caam) 20 MB/s [Offload, CAAM]
AES-128-CBC-ESSIV:
essiv(cbc-aes-caam,sha256-lib) 23 MB/s [Offload, CAAM]
STM32MP157F-DK2:
AES-256-XTS:
xts-aes-neonbs 13.2 MB/s [CPU-based, ARM NEON]
xts(stm32-ecb-aes) 3.1 MB/s [Offload, STM32 crypto engine]
AES-128-CBC-ESSIV:
essiv(cbc-aes-neonbs,sha256-lib)
14.7 MB/s [CPU-based, ARM NEON]
essiv(stm32-cbc-aes,sha256-lib)
3.2 MB/s [Offload, STM32 crypto engine]
Adiantum:
adiantum(xchacha12-arm,aes-arm,nhpoly1305-neon)
52.8 MB/s [CPU-based, ARM scalar + NEON]
So, there was no case in which the crypto engine was even *close* to
being faster. On the first three, which have AES instructions in the
CPU, the CPU was 30 to 55 times faster (!). Even on STM32MP157F-DK2
which has a Cortex-A7 CPU that doesn't have AES instructions, AES was
over 4 times faster on the CPU. And Adiantum encryption, which is what
actually should be used on CPUs like that, was over 17 times faster.
Other justifications that have been given for these non-inline crypto
engines (almost always coming from the hardware vendors, not actual
users) don't seem very plausible either:
- The crypto engine throughput could be improved by processing
multiple requests concurrently. Currently irrelevant to fscrypt,
since it doesn't do that. This would also be complex, and unhelpful
in many cases. 2 of the 4 engines I tested even had only one queue.
- Some of the engines, e.g. STM32, support hardware keys. Also
currently irrelevant to fscrypt, since it doesn't support these.
Interestingly, the STM32 driver itself doesn't support this either.
- Free up CPU for other tasks and/or reduce energy usage. Not very
plausible considering the "short" message length, driver overhead,
and scheduling overhead. There's just very little time for the CPU
to do something else like run another task or enter low-power state,
before the message finishes and it's time to process the next one.
- Some of these engines resist power analysis and electromagnetic
attacks, while the CPU-based crypto generally does not. In theory,
this sounds great. In practice, if this benefit requires the use of
an off-CPU offload that massively regresses performance and has a
low-quality, buggy driver, the price for this hardening (which is
not relevant to most fscrypt users, and tends to be incomplete) is
just too high. Inline crypto engines are much more promising here,
as are on-CPU solutions like RISC-V High Assurance Cryptography.
Fixes: b30ab0e03407 ("ext4 crypto: add ext4 encryption facilities")
Cc: stable(a)vger.kernel.org
Acked-by: Ard Biesheuvel <ardb(a)kernel.org>
Link: https://lore.kernel.org/r/20250704070322.20692-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)kernel.org>
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
index f63791641c1d..696a5844bfa3 100644
--- a/Documentation/filesystems/fscrypt.rst
+++ b/Documentation/filesystems/fscrypt.rst
@@ -147,9 +147,8 @@ However, these ioctls have some limitations:
were wiped. To partially solve this, you can add init_on_free=1 to
your kernel command line. However, this has a performance cost.
-- Secret keys might still exist in CPU registers, in crypto
- accelerator hardware (if used by the crypto API to implement any of
- the algorithms), or in other places not explicitly considered here.
+- Secret keys might still exist in CPU registers or in other places
+ not explicitly considered here.
Full system compromise
~~~~~~~~~~~~~~~~~~~~~~
@@ -406,9 +405,12 @@ the work is done by XChaCha12, which is much faster than AES when AES
acceleration is unavailable. For more information about Adiantum, see
`the Adiantum paper <https://eprint.iacr.org/2018/720.pdf>`_.
-The (AES-128-CBC-ESSIV, AES-128-CBC-CTS) pair exists only to support
-systems whose only form of AES acceleration is an off-CPU crypto
-accelerator such as CAAM or CESA that does not support XTS.
+The (AES-128-CBC-ESSIV, AES-128-CBC-CTS) pair was added to try to
+provide a more efficient option for systems that lack AES instructions
+in the CPU but do have a non-inline crypto engine such as CAAM or CESA
+that supports AES-CBC (and not AES-XTS). This is deprecated. It has
+been shown that just doing AES on the CPU is actually faster.
+Moreover, Adiantum is faster still and is recommended on such systems.
The remaining mode pairs are the "national pride ciphers":
@@ -1318,22 +1320,13 @@ this by validating all top-level encryption policies prior to access.
Inline encryption support
=========================
-By default, fscrypt uses the kernel crypto API for all cryptographic
-operations (other than HKDF, which fscrypt partially implements
-itself). The kernel crypto API supports hardware crypto accelerators,
-but only ones that work in the traditional way where all inputs and
-outputs (e.g. plaintexts and ciphertexts) are in memory. fscrypt can
-take advantage of such hardware, but the traditional acceleration
-model isn't particularly efficient and fscrypt hasn't been optimized
-for it.
-
-Instead, many newer systems (especially mobile SoCs) have *inline
-encryption hardware* that can encrypt/decrypt data while it is on its
-way to/from the storage device. Linux supports inline encryption
-through a set of extensions to the block layer called *blk-crypto*.
-blk-crypto allows filesystems to attach encryption contexts to bios
-(I/O requests) to specify how the data will be encrypted or decrypted
-in-line. For more information about blk-crypto, see
+Many newer systems (especially mobile SoCs) have *inline encryption
+hardware* that can encrypt/decrypt data while it is on its way to/from
+the storage device. Linux supports inline encryption through a set of
+extensions to the block layer called *blk-crypto*. blk-crypto allows
+filesystems to attach encryption contexts to bios (I/O requests) to
+specify how the data will be encrypted or decrypted in-line. For more
+information about blk-crypto, see
:ref:`Documentation/block/inline-encryption.rst <inline_encryption>`.
On supported filesystems (currently ext4 and f2fs), fscrypt can use
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index c1d92074b65c..6e7164530a1e 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -45,6 +45,23 @@
*/
#undef FSCRYPT_MAX_KEY_SIZE
+/*
+ * This mask is passed as the third argument to the crypto_alloc_*() functions
+ * to prevent fscrypt from using the Crypto API drivers for non-inline crypto
+ * engines. Those drivers have been problematic for fscrypt. fscrypt users
+ * have reported hangs and even incorrect en/decryption with these drivers.
+ * Since going to the driver, off CPU, and back again is really slow, such
+ * drivers can be over 50 times slower than the CPU-based code for fscrypt's
+ * workload. Even on platforms that lack AES instructions on the CPU, using the
+ * offloads has been shown to be slower, even staying with AES. (Of course,
+ * Adiantum is faster still, and is the recommended option on such platforms...)
+ *
+ * Note that fscrypt also supports inline crypto engines. Those don't use the
+ * Crypto API and work much better than the old-style (non-inline) engines.
+ */
+#define FSCRYPT_CRYPTOAPI_MASK \
+ (CRYPTO_ALG_ALLOCATES_MEMORY | CRYPTO_ALG_KERN_DRIVER_ONLY)
+
#define FSCRYPT_CONTEXT_V1 1
#define FSCRYPT_CONTEXT_V2 2
diff --git a/fs/crypto/hkdf.c b/fs/crypto/hkdf.c
index 5c095c8aa3b5..b1ef506cd341 100644
--- a/fs/crypto/hkdf.c
+++ b/fs/crypto/hkdf.c
@@ -58,7 +58,7 @@ int fscrypt_init_hkdf(struct fscrypt_hkdf *hkdf, const u8 *master_key,
u8 prk[HKDF_HASHLEN];
int err;
- hmac_tfm = crypto_alloc_shash(HKDF_HMAC_ALG, 0, 0);
+ hmac_tfm = crypto_alloc_shash(HKDF_HMAC_ALG, 0, FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(hmac_tfm)) {
fscrypt_err(NULL, "Error allocating " HKDF_HMAC_ALG ": %ld",
PTR_ERR(hmac_tfm));
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index a67e20d126c9..74d4a2e1ad23 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -104,7 +104,8 @@ fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key,
struct crypto_skcipher *tfm;
int err;
- tfm = crypto_alloc_skcipher(mode->cipher_str, 0, 0);
+ tfm = crypto_alloc_skcipher(mode->cipher_str, 0,
+ FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(tfm)) {
if (PTR_ERR(tfm) == -ENOENT) {
fscrypt_warn(inode,
diff --git a/fs/crypto/keysetup_v1.c b/fs/crypto/keysetup_v1.c
index b70521c55132..158ceae8a5bc 100644
--- a/fs/crypto/keysetup_v1.c
+++ b/fs/crypto/keysetup_v1.c
@@ -52,7 +52,8 @@ static int derive_key_aes(const u8 *master_key,
struct skcipher_request *req = NULL;
DECLARE_CRYPTO_WAIT(wait);
struct scatterlist src_sg, dst_sg;
- struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
+ struct crypto_skcipher *tfm =
+ crypto_alloc_skcipher("ecb(aes)", 0, FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(tfm)) {
res = PTR_ERR(tfm);
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x b41c1d8d07906786c60893980d52688f31d114a6
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081512-filter-droop-370f@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b41c1d8d07906786c60893980d52688f31d114a6 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers(a)kernel.org>
Date: Fri, 4 Jul 2025 00:03:22 -0700
Subject: [PATCH] fscrypt: Don't use problematic non-inline crypto engines
Make fscrypt no longer use Crypto API drivers for non-inline crypto
engines, even when the Crypto API prioritizes them over CPU-based code
(which unfortunately it often does). These drivers tend to be really
problematic, especially for fscrypt's workload. This commit has no
effect on inline crypto engines, which are different and do work well.
Specifically, exclude drivers that have CRYPTO_ALG_KERN_DRIVER_ONLY or
CRYPTO_ALG_ALLOCATES_MEMORY set. (Later, CRYPTO_ALG_ASYNC should be
excluded too. That's omitted for now to keep this commit backportable,
since until recently some CPU-based code had CRYPTO_ALG_ASYNC set.)
There are two major issues with these drivers: bugs and performance.
First, these drivers tend to be buggy. They're fundamentally much more
error-prone and harder to test than the CPU-based code. They often
don't get tested before kernel releases, and even if they do, the crypto
self-tests don't properly test these drivers. Released drivers have
en/decrypted or hashed data incorrectly. These bugs cause issues for
fscrypt users who often didn't even want to use these drivers, e.g.:
- https://github.com/google/fscryptctl/issues/32
- https://github.com/google/fscryptctl/issues/9
- https://lore.kernel.org/r/PH0PR02MB731916ECDB6C613665863B6CFFAA2@PH0PR02MB7…
These drivers have also similarly caused issues for dm-crypt users,
including data corruption and deadlocks. Since Linux v5.10, dm-crypt
has disabled most of them by excluding CRYPTO_ALG_ALLOCATES_MEMORY.
Second, these drivers tend to be *much* slower than the CPU-based code.
This may seem counterintuitive, but benchmarks clearly show it. There's
a *lot* of overhead associated with going to a hardware driver, off the
CPU, and back again. To prove this, I gathered as many systems with
this type of crypto engine as I could, and I measured synchronous
encryption of 4096-byte messages (which matches fscrypt's workload):
Intel Emerald Rapids server:
AES-256-XTS:
xts-aes-vaes-avx512 16171 MB/s [CPU-based, Vector AES]
qat_aes_xts 289 MB/s [Offload, Intel QuickAssist]
Qualcomm SM8650 HDK:
AES-256-XTS:
xts-aes-ce 4301 MB/s [CPU-based, ARMv8 Crypto Extensions]
xts-aes-qce 73 MB/s [Offload, Qualcomm Crypto Engine]
i.MX 8M Nano LPDDR4 EVK:
AES-256-XTS:
xts-aes-ce 647 MB/s [CPU-based, ARMv8 Crypto Extensions]
xts(ecb-aes-caam) 20 MB/s [Offload, CAAM]
AES-128-CBC-ESSIV:
essiv(cbc-aes-caam,sha256-lib) 23 MB/s [Offload, CAAM]
STM32MP157F-DK2:
AES-256-XTS:
xts-aes-neonbs 13.2 MB/s [CPU-based, ARM NEON]
xts(stm32-ecb-aes) 3.1 MB/s [Offload, STM32 crypto engine]
AES-128-CBC-ESSIV:
essiv(cbc-aes-neonbs,sha256-lib)
14.7 MB/s [CPU-based, ARM NEON]
essiv(stm32-cbc-aes,sha256-lib)
3.2 MB/s [Offload, STM32 crypto engine]
Adiantum:
adiantum(xchacha12-arm,aes-arm,nhpoly1305-neon)
52.8 MB/s [CPU-based, ARM scalar + NEON]
So, there was no case in which the crypto engine was even *close* to
being faster. On the first three, which have AES instructions in the
CPU, the CPU was 30 to 55 times faster (!). Even on STM32MP157F-DK2
which has a Cortex-A7 CPU that doesn't have AES instructions, AES was
over 4 times faster on the CPU. And Adiantum encryption, which is what
actually should be used on CPUs like that, was over 17 times faster.
Other justifications that have been given for these non-inline crypto
engines (almost always coming from the hardware vendors, not actual
users) don't seem very plausible either:
- The crypto engine throughput could be improved by processing
multiple requests concurrently. Currently irrelevant to fscrypt,
since it doesn't do that. This would also be complex, and unhelpful
in many cases. 2 of the 4 engines I tested even had only one queue.
- Some of the engines, e.g. STM32, support hardware keys. Also
currently irrelevant to fscrypt, since it doesn't support these.
Interestingly, the STM32 driver itself doesn't support this either.
- Free up CPU for other tasks and/or reduce energy usage. Not very
plausible considering the "short" message length, driver overhead,
and scheduling overhead. There's just very little time for the CPU
to do something else like run another task or enter low-power state,
before the message finishes and it's time to process the next one.
- Some of these engines resist power analysis and electromagnetic
attacks, while the CPU-based crypto generally does not. In theory,
this sounds great. In practice, if this benefit requires the use of
an off-CPU offload that massively regresses performance and has a
low-quality, buggy driver, the price for this hardening (which is
not relevant to most fscrypt users, and tends to be incomplete) is
just too high. Inline crypto engines are much more promising here,
as are on-CPU solutions like RISC-V High Assurance Cryptography.
Fixes: b30ab0e03407 ("ext4 crypto: add ext4 encryption facilities")
Cc: stable(a)vger.kernel.org
Acked-by: Ard Biesheuvel <ardb(a)kernel.org>
Link: https://lore.kernel.org/r/20250704070322.20692-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)kernel.org>
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
index f63791641c1d..696a5844bfa3 100644
--- a/Documentation/filesystems/fscrypt.rst
+++ b/Documentation/filesystems/fscrypt.rst
@@ -147,9 +147,8 @@ However, these ioctls have some limitations:
were wiped. To partially solve this, you can add init_on_free=1 to
your kernel command line. However, this has a performance cost.
-- Secret keys might still exist in CPU registers, in crypto
- accelerator hardware (if used by the crypto API to implement any of
- the algorithms), or in other places not explicitly considered here.
+- Secret keys might still exist in CPU registers or in other places
+ not explicitly considered here.
Full system compromise
~~~~~~~~~~~~~~~~~~~~~~
@@ -406,9 +405,12 @@ the work is done by XChaCha12, which is much faster than AES when AES
acceleration is unavailable. For more information about Adiantum, see
`the Adiantum paper <https://eprint.iacr.org/2018/720.pdf>`_.
-The (AES-128-CBC-ESSIV, AES-128-CBC-CTS) pair exists only to support
-systems whose only form of AES acceleration is an off-CPU crypto
-accelerator such as CAAM or CESA that does not support XTS.
+The (AES-128-CBC-ESSIV, AES-128-CBC-CTS) pair was added to try to
+provide a more efficient option for systems that lack AES instructions
+in the CPU but do have a non-inline crypto engine such as CAAM or CESA
+that supports AES-CBC (and not AES-XTS). This is deprecated. It has
+been shown that just doing AES on the CPU is actually faster.
+Moreover, Adiantum is faster still and is recommended on such systems.
The remaining mode pairs are the "national pride ciphers":
@@ -1318,22 +1320,13 @@ this by validating all top-level encryption policies prior to access.
Inline encryption support
=========================
-By default, fscrypt uses the kernel crypto API for all cryptographic
-operations (other than HKDF, which fscrypt partially implements
-itself). The kernel crypto API supports hardware crypto accelerators,
-but only ones that work in the traditional way where all inputs and
-outputs (e.g. plaintexts and ciphertexts) are in memory. fscrypt can
-take advantage of such hardware, but the traditional acceleration
-model isn't particularly efficient and fscrypt hasn't been optimized
-for it.
-
-Instead, many newer systems (especially mobile SoCs) have *inline
-encryption hardware* that can encrypt/decrypt data while it is on its
-way to/from the storage device. Linux supports inline encryption
-through a set of extensions to the block layer called *blk-crypto*.
-blk-crypto allows filesystems to attach encryption contexts to bios
-(I/O requests) to specify how the data will be encrypted or decrypted
-in-line. For more information about blk-crypto, see
+Many newer systems (especially mobile SoCs) have *inline encryption
+hardware* that can encrypt/decrypt data while it is on its way to/from
+the storage device. Linux supports inline encryption through a set of
+extensions to the block layer called *blk-crypto*. blk-crypto allows
+filesystems to attach encryption contexts to bios (I/O requests) to
+specify how the data will be encrypted or decrypted in-line. For more
+information about blk-crypto, see
:ref:`Documentation/block/inline-encryption.rst <inline_encryption>`.
On supported filesystems (currently ext4 and f2fs), fscrypt can use
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index c1d92074b65c..6e7164530a1e 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -45,6 +45,23 @@
*/
#undef FSCRYPT_MAX_KEY_SIZE
+/*
+ * This mask is passed as the third argument to the crypto_alloc_*() functions
+ * to prevent fscrypt from using the Crypto API drivers for non-inline crypto
+ * engines. Those drivers have been problematic for fscrypt. fscrypt users
+ * have reported hangs and even incorrect en/decryption with these drivers.
+ * Since going to the driver, off CPU, and back again is really slow, such
+ * drivers can be over 50 times slower than the CPU-based code for fscrypt's
+ * workload. Even on platforms that lack AES instructions on the CPU, using the
+ * offloads has been shown to be slower, even staying with AES. (Of course,
+ * Adiantum is faster still, and is the recommended option on such platforms...)
+ *
+ * Note that fscrypt also supports inline crypto engines. Those don't use the
+ * Crypto API and work much better than the old-style (non-inline) engines.
+ */
+#define FSCRYPT_CRYPTOAPI_MASK \
+ (CRYPTO_ALG_ALLOCATES_MEMORY | CRYPTO_ALG_KERN_DRIVER_ONLY)
+
#define FSCRYPT_CONTEXT_V1 1
#define FSCRYPT_CONTEXT_V2 2
diff --git a/fs/crypto/hkdf.c b/fs/crypto/hkdf.c
index 5c095c8aa3b5..b1ef506cd341 100644
--- a/fs/crypto/hkdf.c
+++ b/fs/crypto/hkdf.c
@@ -58,7 +58,7 @@ int fscrypt_init_hkdf(struct fscrypt_hkdf *hkdf, const u8 *master_key,
u8 prk[HKDF_HASHLEN];
int err;
- hmac_tfm = crypto_alloc_shash(HKDF_HMAC_ALG, 0, 0);
+ hmac_tfm = crypto_alloc_shash(HKDF_HMAC_ALG, 0, FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(hmac_tfm)) {
fscrypt_err(NULL, "Error allocating " HKDF_HMAC_ALG ": %ld",
PTR_ERR(hmac_tfm));
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index a67e20d126c9..74d4a2e1ad23 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -104,7 +104,8 @@ fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key,
struct crypto_skcipher *tfm;
int err;
- tfm = crypto_alloc_skcipher(mode->cipher_str, 0, 0);
+ tfm = crypto_alloc_skcipher(mode->cipher_str, 0,
+ FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(tfm)) {
if (PTR_ERR(tfm) == -ENOENT) {
fscrypt_warn(inode,
diff --git a/fs/crypto/keysetup_v1.c b/fs/crypto/keysetup_v1.c
index b70521c55132..158ceae8a5bc 100644
--- a/fs/crypto/keysetup_v1.c
+++ b/fs/crypto/keysetup_v1.c
@@ -52,7 +52,8 @@ static int derive_key_aes(const u8 *master_key,
struct skcipher_request *req = NULL;
DECLARE_CRYPTO_WAIT(wait);
struct scatterlist src_sg, dst_sg;
- struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
+ struct crypto_skcipher *tfm =
+ crypto_alloc_skcipher("ecb(aes)", 0, FSCRYPT_CRYPTOAPI_MASK);
if (IS_ERR(tfm)) {
res = PTR_ERR(tfm);
So we've had this regression in 9p for.. almost a year, which is way too
long, but there was no "easy" reproducer until yesterday (thank you
again!!)
It turned out to be a bug with iov_iter on folios,
iov_iter_get_pages_alloc2() would advance the iov_iter correctly up to
the end edge of a folio and the later copy_to_iter() fails on the
iterate_folioq() bug.
Happy to consider alternative ways of fixing this, now there's a
reproducer it's all much clearer; for the bug to be visible we basically
need to make and IO with non-contiguous folios in the iov_iter which is
not obvious to test with synthetic VMs, with size that triggers a
zero-copy read followed by a non-zero-copy read.
Signed-off-by: Dominique Martinet <asmadeus(a)codewreck.org>
---
Changes in v3:
- convert 'goto next' to a big "if there is valid data in current folio"
Future optimizations can remove it again after making sure this (iov iter
advanced to end of folio) can never happen.
- Link to v2: https://lore.kernel.org/r/20250812-iot_iter_folio-v2-0-f99423309478@codewre…
Changes in v2:
- Fixed 'remain' being used uninitialized in iterate_folioq when going
through the goto
- s/forwarded/advanced in commit message
- Link to v1: https://lore.kernel.org/r/20250811-iot_iter_folio-v1-0-d9c223adf93c@codewre…
---
Dominique Martinet (2):
iov_iter: iterate_folioq: fix handling of offset >= folio size
iov_iter: iov_folioq_get_pages: don't leave empty slot behind
include/linux/iov_iter.h | 20 +++++++++++---------
lib/iov_iter.c | 6 +++---
2 files changed, 14 insertions(+), 12 deletions(-)
---
base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
change-id: 20250811-iot_iter_folio-1b7849f88fed
Best regards,
--
Dominique Martinet <asmadeus(a)codewreck.org>
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 908e4ead7f757504d8b345452730636e298cbf68
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081525-comprised-nastily-418e@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 908e4ead7f757504d8b345452730636e298cbf68 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton(a)kernel.org>
Date: Wed, 4 Jun 2025 12:01:10 -0400
Subject: [PATCH] nfsd: handle get_client_locked() failure in
nfsd4_setclientid_confirm()
Lei Lu recently reported that nfsd4_setclientid_confirm() did not check
the return value from get_client_locked(). a SETCLIENTID_CONFIRM could
race with a confirmed client expiring and fail to get a reference. That
could later lead to a UAF.
Fix this by getting a reference early in the case where there is an
extant confirmed client. If that fails then treat it as if there were no
confirmed client found at all.
In the case where the unconfirmed client is expiring, just fail and
return the result from get_client_locked().
Reported-by: lei lu <llfamsec(a)gmail.com>
Closes: https://lore.kernel.org/linux-nfs/CAEBF3_b=UvqzNKdnfD_52L05Mqrqui9vZ2eFamgA…
Fixes: d20c11d86d8f ("nfsd: Protect session creation and client confirm using client_lock")
Cc: stable(a)vger.kernel.org
Signed-off-by: Jeff Layton <jlayton(a)kernel.org>
Signed-off-by: Chuck Lever <chuck.lever(a)oracle.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index a0e3fa2718c7..95d88555648d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -4690,10 +4690,16 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
}
status = nfs_ok;
if (conf) {
- old = unconf;
- unhash_client_locked(old);
- nfsd4_change_callback(conf, &unconf->cl_cb_conn);
- } else {
+ if (get_client_locked(conf) == nfs_ok) {
+ old = unconf;
+ unhash_client_locked(old);
+ nfsd4_change_callback(conf, &unconf->cl_cb_conn);
+ } else {
+ conf = NULL;
+ }
+ }
+
+ if (!conf) {
old = find_confirmed_client_by_name(&unconf->cl_name, nn);
if (old) {
status = nfserr_clid_inuse;
@@ -4710,10 +4716,14 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
}
trace_nfsd_clid_replaced(&old->cl_clientid);
}
+ status = get_client_locked(unconf);
+ if (status != nfs_ok) {
+ old = NULL;
+ goto out;
+ }
move_to_confirmed(unconf);
conf = unconf;
}
- get_client_locked(conf);
spin_unlock(&nn->client_lock);
if (conf == unconf)
fsnotify_dentry(conf->cl_nfsd_info_dentry, FS_MODIFY);
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 70458f8a6b44daf3ad39f0d9b6d1097c8a7780ed
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081557-glimmer-distill-dc47@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 70458f8a6b44daf3ad39f0d9b6d1097c8a7780ed Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan(a)kernel.org>
Date: Fri, 25 Jul 2025 19:12:10 +0200
Subject: [PATCH] net: enetc: fix device and OF node leak at probe
Make sure to drop the references to the IERB OF node and platform device
taken by of_parse_phandle() and of_find_device_by_node() during probe.
Fixes: e7d48e5fbf30 ("net: enetc: add a mini driver for the Integrated Endpoint Register Block")
Cc: stable(a)vger.kernel.org # 5.13
Cc: Vladimir Oltean <vladimir.oltean(a)nxp.com>
Signed-off-by: Johan Hovold <johan(a)kernel.org>
Reviewed-by: Simon Horman <horms(a)kernel.org>
Link: https://patch.msgid.link/20250725171213.880-3-johan@kernel.org
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index f63a29e2e031..de0fb272c847 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -829,19 +829,29 @@ static int enetc_pf_register_with_ierb(struct pci_dev *pdev)
{
struct platform_device *ierb_pdev;
struct device_node *ierb_node;
+ int ret;
ierb_node = of_find_compatible_node(NULL, NULL,
"fsl,ls1028a-enetc-ierb");
- if (!ierb_node || !of_device_is_available(ierb_node))
+ if (!ierb_node)
return -ENODEV;
+ if (!of_device_is_available(ierb_node)) {
+ of_node_put(ierb_node);
+ return -ENODEV;
+ }
+
ierb_pdev = of_find_device_by_node(ierb_node);
of_node_put(ierb_node);
if (!ierb_pdev)
return -EPROBE_DEFER;
- return enetc_ierb_register_pf(ierb_pdev, pdev);
+ ret = enetc_ierb_register_pf(ierb_pdev, pdev);
+
+ put_device(&ierb_pdev->dev);
+
+ return ret;
}
static const struct enetc_si_ops enetc_psi_ops = {
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 70458f8a6b44daf3ad39f0d9b6d1097c8a7780ed
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081556-icon-nursing-ee42@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 70458f8a6b44daf3ad39f0d9b6d1097c8a7780ed Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan(a)kernel.org>
Date: Fri, 25 Jul 2025 19:12:10 +0200
Subject: [PATCH] net: enetc: fix device and OF node leak at probe
Make sure to drop the references to the IERB OF node and platform device
taken by of_parse_phandle() and of_find_device_by_node() during probe.
Fixes: e7d48e5fbf30 ("net: enetc: add a mini driver for the Integrated Endpoint Register Block")
Cc: stable(a)vger.kernel.org # 5.13
Cc: Vladimir Oltean <vladimir.oltean(a)nxp.com>
Signed-off-by: Johan Hovold <johan(a)kernel.org>
Reviewed-by: Simon Horman <horms(a)kernel.org>
Link: https://patch.msgid.link/20250725171213.880-3-johan@kernel.org
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index f63a29e2e031..de0fb272c847 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -829,19 +829,29 @@ static int enetc_pf_register_with_ierb(struct pci_dev *pdev)
{
struct platform_device *ierb_pdev;
struct device_node *ierb_node;
+ int ret;
ierb_node = of_find_compatible_node(NULL, NULL,
"fsl,ls1028a-enetc-ierb");
- if (!ierb_node || !of_device_is_available(ierb_node))
+ if (!ierb_node)
return -ENODEV;
+ if (!of_device_is_available(ierb_node)) {
+ of_node_put(ierb_node);
+ return -ENODEV;
+ }
+
ierb_pdev = of_find_device_by_node(ierb_node);
of_node_put(ierb_node);
if (!ierb_pdev)
return -EPROBE_DEFER;
- return enetc_ierb_register_pf(ierb_pdev, pdev);
+ ret = enetc_ierb_register_pf(ierb_pdev, pdev);
+
+ put_device(&ierb_pdev->dev);
+
+ return ret;
}
static const struct enetc_si_ops enetc_psi_ops = {
Hi,
Please apply the commit e37617c8e53a1f7fcba6d5e1041f4fd8a2425c27,
it fix the REGRESSION by ada8d7fa0ad49a2a078f97f7f6e02d24d3c357a3
("sched/cpufreq: Rework schedutil governor performance estimation") which
introduced in v6.6.89.
Best Regards
Wentao Guan
The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 65ba2a6e77e9e5c843a591055789050e77b5c65e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081521-dangle-drapery-9a9a@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 65ba2a6e77e9e5c843a591055789050e77b5c65e Mon Sep 17 00:00:00 2001
From: Siddharth Vadapalli <s-vadapalli(a)ti.com>
Date: Mon, 23 Jun 2025 15:36:57 +0530
Subject: [PATCH] arm64: dts: ti: k3-j722s-evm: Fix USB gpio-hog level for
Type-C
According to the "GPIO Expander Map / Table" section of the J722S EVM
Schematic within the Evaluation Module Design Files package [0], the
GPIO Pin P05 located on the GPIO Expander 1 (I2C0/0x23) has to be pulled
down to select the Type-C interface. Since commit under Fixes claims to
enable the Type-C interface, update the property within "p05-hog" from
"output-high" to "output-low", thereby switching from the Type-A
interface to the Type-C interface.
[0]: https://www.ti.com/lit/zip/sprr495
Cc: stable(a)vger.kernel.org
Fixes: 485705df5d5f ("arm64: dts: ti: k3-j722s: Enable PCIe and USB support on J722S-EVM")
Signed-off-by: Siddharth Vadapalli <s-vadapalli(a)ti.com>
Link: https://lore.kernel.org/r/20250623100657.4082031-1-s-vadapalli@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr(a)ti.com>
diff --git a/arch/arm64/boot/dts/ti/k3-j722s-evm.dts b/arch/arm64/boot/dts/ti/k3-j722s-evm.dts
index a47852fdca70..d0533723412a 100644
--- a/arch/arm64/boot/dts/ti/k3-j722s-evm.dts
+++ b/arch/arm64/boot/dts/ti/k3-j722s-evm.dts
@@ -634,7 +634,7 @@ p05-hog {
/* P05 - USB2.0_MUX_SEL */
gpio-hog;
gpios = <5 GPIO_ACTIVE_LOW>;
- output-high;
+ output-low;
};
p01_hog: p01-hog {
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x f2e467a48287c868818085aa35389a224d226732
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025081535-enrage-raging-295b@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f2e467a48287c868818085aa35389a224d226732 Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Fri, 11 Jul 2025 18:33:36 +0200
Subject: [PATCH] eventpoll: Fix semi-unbounded recursion
Ensure that epoll instances can never form a graph deeper than
EP_MAX_NESTS+1 links.
Currently, ep_loop_check_proc() ensures that the graph is loop-free and
does some recursion depth checks, but those recursion depth checks don't
limit the depth of the resulting tree for two reasons:
- They don't look upwards in the tree.
- If there are multiple downwards paths of different lengths, only one of
the paths is actually considered for the depth check since commit
28d82dc1c4ed ("epoll: limit paths").
Essentially, the current recursion depth check in ep_loop_check_proc() just
serves to prevent it from recursing too deeply while checking for loops.
A more thorough check is done in reverse_path_check() after the new graph
edge has already been created; this checks, among other things, that no
paths going upwards from any non-epoll file with a length of more than 5
edges exist. However, this check does not apply to non-epoll files.
As a result, it is possible to recurse to a depth of at least roughly 500,
tested on v6.15. (I am unsure if deeper recursion is possible; and this may
have changed with commit 8c44dac8add7 ("eventpoll: Fix priority inversion
problem").)
To fix it:
1. In ep_loop_check_proc(), note the subtree depth of each visited node,
and use subtree depths for the total depth calculation even when a subtree
has already been visited.
2. Add ep_get_upwards_depth_proc() for similarly determining the maximum
depth of an upwards walk.
3. In ep_loop_check(), use these values to limit the total path length
between epoll nodes to EP_MAX_NESTS edges.
Fixes: 22bacca48a17 ("epoll: prevent creating circular epoll structures")
Cc: stable(a)vger.kernel.org
Signed-off-by: Jann Horn <jannh(a)google.com>
Link: https://lore.kernel.org/20250711-epoll-recursion-fix-v1-1-fb2457c33292@goog…
Signed-off-by: Christian Brauner <brauner(a)kernel.org>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index d4dbffdedd08..44648cc09250 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -218,6 +218,7 @@ struct eventpoll {
/* used to optimize loop detection check */
u64 gen;
struct hlist_head refs;
+ u8 loop_check_depth;
/*
* usage count, used together with epitem->dying to
@@ -2142,23 +2143,24 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
}
/**
- * ep_loop_check_proc - verify that adding an epoll file inside another
- * epoll structure does not violate the constraints, in
- * terms of closed loops, or too deep chains (which can
- * result in excessive stack usage).
+ * ep_loop_check_proc - verify that adding an epoll file @ep inside another
+ * epoll file does not create closed loops, and
+ * determine the depth of the subtree starting at @ep
*
* @ep: the &struct eventpoll to be currently checked.
* @depth: Current depth of the path being checked.
*
- * Return: %zero if adding the epoll @file inside current epoll
- * structure @ep does not violate the constraints, or %-1 otherwise.
+ * Return: depth of the subtree, or INT_MAX if we found a loop or went too deep.
*/
static int ep_loop_check_proc(struct eventpoll *ep, int depth)
{
- int error = 0;
+ int result = 0;
struct rb_node *rbp;
struct epitem *epi;
+ if (ep->gen == loop_check_gen)
+ return ep->loop_check_depth;
+
mutex_lock_nested(&ep->mtx, depth + 1);
ep->gen = loop_check_gen;
for (rbp = rb_first_cached(&ep->rbr); rbp; rbp = rb_next(rbp)) {
@@ -2166,13 +2168,11 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth)
if (unlikely(is_file_epoll(epi->ffd.file))) {
struct eventpoll *ep_tovisit;
ep_tovisit = epi->ffd.file->private_data;
- if (ep_tovisit->gen == loop_check_gen)
- continue;
if (ep_tovisit == inserting_into || depth > EP_MAX_NESTS)
- error = -1;
+ result = INT_MAX;
else
- error = ep_loop_check_proc(ep_tovisit, depth + 1);
- if (error != 0)
+ result = max(result, ep_loop_check_proc(ep_tovisit, depth + 1) + 1);
+ if (result > EP_MAX_NESTS)
break;
} else {
/*
@@ -2186,9 +2186,27 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth)
list_file(epi->ffd.file);
}
}
+ ep->loop_check_depth = result;
mutex_unlock(&ep->mtx);
- return error;
+ return result;
+}
+
+/**
+ * ep_get_upwards_depth_proc - determine depth of @ep when traversed upwards
+ */
+static int ep_get_upwards_depth_proc(struct eventpoll *ep, int depth)
+{
+ int result = 0;
+ struct epitem *epi;
+
+ if (ep->gen == loop_check_gen)
+ return ep->loop_check_depth;
+ hlist_for_each_entry_rcu(epi, &ep->refs, fllink)
+ result = max(result, ep_get_upwards_depth_proc(epi->ep, depth + 1) + 1);
+ ep->gen = loop_check_gen;
+ ep->loop_check_depth = result;
+ return result;
}
/**
@@ -2204,8 +2222,22 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth)
*/
static int ep_loop_check(struct eventpoll *ep, struct eventpoll *to)
{
+ int depth, upwards_depth;
+
inserting_into = ep;
- return ep_loop_check_proc(to, 0);
+ /*
+ * Check how deep down we can get from @to, and whether it is possible
+ * to loop up to @ep.
+ */
+ depth = ep_loop_check_proc(to, 0);
+ if (depth > EP_MAX_NESTS)
+ return -1;
+ /* Check how far up we can go from @ep. */
+ rcu_read_lock();
+ upwards_depth = ep_get_upwards_depth_proc(ep, 0);
+ rcu_read_unlock();
+
+ return (depth+1+upwards_depth > EP_MAX_NESTS) ? -1 : 0;
}
static void clear_tfile_check_list(void)