From: Christoph Hellwig <hch(a)lst.de>
[ Upstream commit bf4c89fc8797f5c0964a0c3d561fbe7e8483b62f ]
Commit b222dd2fdd53 ("block: call bio_uninit in bio_endio") added a call
to bio_uninit in bio_endio to work around callers that use bio_init but
fail to call bio_uninit after they are done to release the resources.
While this is an abuse of the bio_init API we still have quite a few of
those left. But this early uninit causes a problem for integrity data,
as at least some users need the bio_integrity_payload. Right now the
only one is the NVMe passthrough which archives this by adding a special
case to skip the freeing if the BIP_INTEGRITY_USER flag is set.
Sort this out by only putting bi_blkg in bio_endio as that is the cause
of the actual leaks - the few users of the crypto context and integrity
data all properly call bio_uninit, usually through bio_put for
dynamically allocated bios.
Signed-off-by: Christoph Hellwig <hch(a)lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen(a)oracle.com>
Link: https://lore.kernel.org/r/20240702151047.1746127-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
block/bio.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index e9e809a63c597..c7a4bc05c43e7 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1630,8 +1630,18 @@ void bio_endio(struct bio *bio)
goto again;
}
- /* release cgroup info */
- bio_uninit(bio);
+#ifdef CONFIG_BLK_CGROUP
+ /*
+ * Release cgroup info. We shouldn't have to do this here, but quite
+ * a few callers of bio_init fail to call bio_uninit, so we cover up
+ * for that here at least for now.
+ */
+ if (bio->bi_blkg) {
+ blkg_put(bio->bi_blkg);
+ bio->bi_blkg = NULL;
+ }
+#endif
+
if (bio->bi_end_io)
bio->bi_end_io(bio);
}
--
2.43.0
On the off chance that clock value ends up being too high (by means
of skl_ddi_calculate_wrpll() having benn called with big enough
value of crtc_state->port_clock * 1000), one possible consequence
may be that the result will not be able to fit into signed int.
Fix this issue by moving conversion of clock parameter from kHz to Hz
into the body of skl_ddi_calculate_wrpll(), as well as casting the
same parameter to u64 type while calculating the value for AFE clock.
This both mitigates the overflow problem and avoids possible erroneous
integer promotion mishaps.
Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.
Fixes: fe70b262e781 ("drm/i915: Move a bunch of stuff into rodata from the stack")
Cc: stable(a)vger.kernel.org
Signed-off-by: Nikita Zhandarovich <n.zhandarovich(a)fintech.ru>
---
v2: instead of double casting of 'clock' with (u64)(u32), convert
'clock' to Hz inside skl_ddi_calculate_wrpll() and cast it only
to u64 to mitigate the issue. Per Jani's <jani.nikula(a)linux.intel.com>
helpful suggestion made here:
https://lore.kernel.org/all/87ed7gzhin.fsf@intel.com/
Also, change commit description accordingly.
v1: https://lore.kernel.org/all/20240724184911.12250-1-n.zhandarovich@fintech.r…
drivers/gpu/drm/i915/display/intel_dpll_mgr.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dpll_mgr.c b/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
index 90998b037349..292d163036b1 100644
--- a/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
+++ b/drivers/gpu/drm/i915/display/intel_dpll_mgr.c
@@ -1658,7 +1658,7 @@ static void skl_wrpll_params_populate(struct skl_wrpll_params *params,
}
static int
-skl_ddi_calculate_wrpll(int clock /* in Hz */,
+skl_ddi_calculate_wrpll(int clock,
int ref_clock,
struct skl_wrpll_params *wrpll_params)
{
@@ -1683,7 +1683,7 @@ skl_ddi_calculate_wrpll(int clock /* in Hz */,
};
unsigned int dco, d, i;
unsigned int p0, p1, p2;
- u64 afe_clock = clock * 5; /* AFE Clock is 5x Pixel clock */
+ u64 afe_clock = (u64)clock * 1000 * 5; /* AFE Clock is 5x Pixel clock, in Hz */
for (d = 0; d < ARRAY_SIZE(dividers); d++) {
for (dco = 0; dco < ARRAY_SIZE(dco_central_freq); dco++) {
@@ -1808,7 +1808,7 @@ static int skl_ddi_hdmi_pll_dividers(struct intel_crtc_state *crtc_state)
struct skl_wrpll_params wrpll_params = {};
int ret;
- ret = skl_ddi_calculate_wrpll(crtc_state->port_clock * 1000,
+ ret = skl_ddi_calculate_wrpll(crtc_state->port_clock,
i915->display.dpll.ref_clks.nssc, &wrpll_params);
if (ret)
return ret;
commit 11a1f4bc47362700fcbde717292158873fb847ed upstream.
Keith reports a use-after-free when a DPC event occurs concurrently to
hot-removal of the same portion of the hierarchy:
The dpc_handler() awaits readiness of the secondary bus below the
Downstream Port where the DPC event occurred. To do so, it polls the
config space of the first child device on the secondary bus. If that
child device is concurrently removed, accesses to its struct pci_dev
cause the kernel to oops.
That's because pci_bridge_wait_for_secondary_bus() neglects to hold a
reference on the child device. Before v6.3, the function was only
called on resume from system sleep or on runtime resume. Holding a
reference wasn't necessary back then because the pciehp IRQ thread
could never run concurrently. (On resume from system sleep, IRQs are
not enabled until after the resume_noirq phase. And runtime resume is
always awaited before a PCI device is removed.)
However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also
called on a DPC event. Commit 53b54ad074de ("PCI/DPC: Await readiness
of secondary bus after reset"), which introduced that, failed to
appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a
reference on the child device because dpc_handler() and pciehp may
indeed run concurrently. The commit was backported to v5.10+ stable
kernels, so that's the oldest one affected.
Add the missing reference acquisition.
Abridged stack trace:
BUG: unable to handle page fault for address: 00000000091400c0
CPU: 15 PID: 2464 Comm: irq/53-pcie-dpc 6.9.0
RIP: pci_bus_read_config_dword+0x17/0x50
pci_dev_wait()
pci_bridge_wait_for_secondary_bus()
dpc_reset_link()
pcie_do_recovery()
dpc_handler()
Fixes: 53b54ad074de ("PCI/DPC: Await readiness of secondary bus after reset")
Closes: https://lore.kernel.org/r/20240612181625.3604512-3-kbusch@meta.com/
Link: https://lore.kernel.org/linux-pci/8e4bcd4116fd94f592f2bf2749f168099c480ddf.…
Reported-by: Keith Busch <kbusch(a)kernel.org>
Tested-by: Keith Busch <kbusch(a)kernel.org>
Signed-off-by: Lukas Wunner <lukas(a)wunner.de>
Signed-off-by: Krzysztof Wilczyński <kwilczynski(a)kernel.org>
Reviewed-by: Keith Busch <kbusch(a)kernel.org>
Reviewed-by: Mika Westerberg <mika.westerberg(a)linux.intel.com>
Cc: stable(a)vger.kernel.org # v5.10+
---
drivers/pci/pci.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 67216f4ea215..a88909f2ae65 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4916,7 +4916,7 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type,
int timeout)
{
struct pci_dev *child;
- int delay;
+ int delay, ret = 0;
if (pci_dev_is_disconnected(dev))
return 0;
@@ -4944,8 +4944,8 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type,
return 0;
}
- child = list_first_entry(&dev->subordinate->devices, struct pci_dev,
- bus_list);
+ child = pci_dev_get(list_first_entry(&dev->subordinate->devices,
+ struct pci_dev, bus_list));
up_read(&pci_bus_sem);
/*
@@ -4955,7 +4955,7 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type,
if (!pci_is_pcie(dev)) {
pci_dbg(dev, "waiting %d ms for secondary bus\n", 1000 + delay);
msleep(1000 + delay);
- return 0;
+ goto put_child;
}
/*
@@ -4976,7 +4976,7 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type,
* until the timeout expires.
*/
if (!pcie_downstream_port(dev))
- return 0;
+ goto put_child;
if (pcie_get_speed_cap(dev) <= PCIE_SPEED_5_0GT) {
pci_dbg(dev, "waiting %d ms for downstream link\n", delay);
@@ -4987,11 +4987,16 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type,
if (!pcie_wait_for_link_delay(dev, true, delay)) {
/* Did not train, no need to wait any further */
pci_info(dev, "Data Link Layer Link Active not set in 1000 msec\n");
- return -ENOTTY;
+ ret = -ENOTTY;
+ goto put_child;
}
}
- return pci_dev_wait(child, reset_type, timeout - delay);
+ ret = pci_dev_wait(child, reset_type, timeout - delay);
+
+put_child:
+ pci_dev_put(child);
+ return ret;
}
void pci_reset_secondary_bus(struct pci_dev *dev)
--
2.43.0