kernel/linux.git/drivers/char/hw_random, branch v6.1.2

hwrng: geode - Fix PCI device refcount leak

2022-12-31T12:32:37+00:00

[ Upstream commit 9f6ec8dc574efb7f4f3d7ee9cd59ae307e78f445 ] for_each_pci_dev() is implemented by pci_get_device(). The comment of pci_get_device() says that it will increase the reference count for the returned pci_dev and also decrease the reference count for the input pci_dev @from if it is not NULL. If we break for_each_pci_dev() loop with pdev not NULL, we need to call pci_dev_put() to decrease the reference count. We add a new struct 'amd_geode_priv' to record pointer of the pci_dev and membase, and then add missing pci_dev_put() for the normal and error path. Fixes: ef5d862734b8 ("[PATCH] Add Geode HW RNG driver") Signed-off-by: Xiongfeng Wang Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

hwrng: amd - Fix PCI device refcount leak

2022-12-31T12:32:37+00:00

[ Upstream commit ecadb5b0111ea19fc7c240bb25d424a94471eb7d ] for_each_pci_dev() is implemented by pci_get_device(). The comment of pci_get_device() says that it will increase the reference count for the returned pci_dev and also decrease the reference count for the input pci_dev @from if it is not NULL. If we break for_each_pci_dev() loop with pdev not NULL, we need to call pci_dev_put() to decrease the reference count. Add the missing pci_dev_put() for the normal and error path. Fixes: 96d63c0297cc ("[PATCH] Add AMD HW RNG driver") Signed-off-by: Xiongfeng Wang Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

hwrng: bcm2835 - use hwrng_msleep() instead of cpu_relax()

2022-10-14T11:03:09+00:00

Rather than busy looping, yield back to the scheduler and sleep for a bit in the event that there's no data. This should hopefully prevent the stalls that Mark reported: <6>[ 3.362859] Freeing initrd memory: 16196K <3>[ 23.160131] rcu: INFO: rcu_sched self-detected stall on CPU <3>[ 23.166057] rcu: 0-....: (2099 ticks this GP) idle=03b4/1/0x40000002 softirq=28/28 fqs=1050 <4>[ 23.174895] (t=2101 jiffies g=-1147 q=2353 ncpus=4) <4>[ 23.180203] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 <4>[ 23.186125] Hardware name: BCM2835 <4>[ 23.189837] PC is at bcm2835_rng_read+0x30/0x6c <4>[ 23.194709] LR is at hwrng_fillfn+0x71/0xf4 <4>[ 23.199218] pc : [] lr : [] psr: 40000033 <4>[ 23.205840] sp : f093df70 ip : 00000000 fp : 00000000 <4>[ 23.211404] r10: c3c7e800 r9 : 00000000 r8 : c17e6b20 <4>[ 23.216968] r7 : c17e6b64 r6 : c18b0a74 r5 : c07ccd99 r4 : c3f171c0 <4>[ 23.223855] r3 : 000fffff r2 : 00000040 r1 : c3c7e800 r0 : c3f171c0 <4>[ 23.230743] Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA Thumb Segment none <4>[ 23.238426] Control: 50c5387d Table: 0020406a DAC: 00000051 <4>[ 23.244519] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 Link: https://lore.kernel.org/all/Y0QJLauamRnCDUef@sirena.org.uk/ Signed-off-by: Jason A. Donenfeld Acked-by: Florian Fainelli Signed-off-by: Herbert Xu

hwrng: core - start hwrng kthread also for untrusted sources

2022-09-30T05:59:12+00:00

Start the hwrng kthread even if the hwrng source has a quality setting of zero. Then, every crng reseed interval, one batch of data from this zero-quality hwrng source will be mixed into the CRNG pool. This patch is based on the assumption that data from a hwrng source will not actively harm the CRNG state. Instead, many hwrng sources (such as TPM devices), even though they are assigend a quality level of zero, actually provide some entropy, which is good enough to mix into the CRNG pool every once in a while. Cc: Herbert Xu Cc: Jason A. Donenfeld Signed-off-by: Dominik Brodowski Signed-off-by: Herbert Xu

hwrng: imx-rngc - Moving IRQ handler registering after imx_rngc_irq_mask_clear()

2022-09-02T10:37:23+00:00

Issue: While servicing interrupt, if the IRQ happens to be because of a SEED_DONE due to a previous boot stage, you end up completing the completion prematurely, hence causing kernel to crash while booting. Fix: Moving IRQ handler registering after imx_rngc_irq_mask_clear() Fixes: 1d5449445bd0 (hwrng: mx-rngc - add a driver for Freescale RNGC) Signed-off-by: Kshitiz Varshney Signed-off-by: Herbert Xu

hwrng: imx-rngc - use devres for hwrng registration

2022-08-26T10:49:10+00:00

Replace hwrng_register with devm_hwrng_register and let devres unregister our hwrng when the device is removed. It's possible to do this now that devres also handles clock disable+uprepare. When we had to disable+unprepare the clock ourselves, we had to unregister the hwrng before this and couldn't use devres. There's nothing left to do for imx_rngc_remove, this function can go. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: imx-rngc - use devm_clk_get_enabled

2022-08-26T10:49:10+00:00

Use the new devm_clk_get_enabled function to get our clock. We don't have to disable and unprepare the clock ourselves any more in error paths and in the remove function. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: imx-rngc - use KBUILD_MODNAME as driver name

2022-08-19T10:39:39+00:00

Use KBUILD_MODNAME instead of hard coding the driver name. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: arm-smccc-trng - fix NO_ENTROPY handling

2022-08-19T10:39:35+00:00

The SMCCC_RET_TRNG_NO_ENTROPY switch arm is never used because the NO_ENTROPY return value is negative and negative values are handled above the switch by immediately returning. Fix by handling errors using a default arm in the switch. Fixes: 0888d04b47a1 ("hwrng: Add Arm SMCCC TRNG based driver") Signed-off-by: James Cowgill Signed-off-by: Herbert Xu

hwrng: core - let sleep be interrupted when unregistering hwrng

2022-08-19T10:39:34+00:00

There are two deadlock scenarios that need addressing, which cause problems when the computer goes to sleep, the interface is set down, and hwrng_unregister() is called. When the deadlock is hit, sleep is delayed for tens of seconds, causing it to fail. These scenarios are: 1) The hwrng kthread can't be stopped while it's sleeping, because it uses msleep_interruptible() which does not react to kthread_stop. 2) A normal user thread can't be interrupted by hwrng_unregister() while it's sleeping, because hwrng_unregister() is called from elsewhere. We solve both issues by add a completion object called dying that fulfils waiters once we have started the process in hwrng_unregister. At the same time, we should cleanup a common and useless dmesg splat in the same area. Cc: Reported-by: Gregory Erwin Fixes: fcd09c90c3c5 ("ath9k: use hw_random API instead of directly dumping into random.c") Link: https://lore.kernel.org/all/CAO+Okf6ZJC5-nTE_EJUGQtd8JiCkiEHytGgDsFGTEjs0c00giw@mail.gmail.com/ Link: https://lore.kernel.org/lkml/CAO+Okf5k+C+SE6pMVfPf-d8MfVPVq4PO7EY8Hys_DVXtent3HA@mail.gmail.com/ Link: https://bugs.archlinux.org/task/75138 Signed-off-by: Jason A. Donenfeld Signed-off-by: Herbert Xu Acked-by: Toke Høiland-Jørgensen Acked-by: Kalle Valo Signed-off-by: Herbert Xu