/* * Copyright (c) 2016 Qualcomm Atheros, Inc * * GPL v2 * * Based on net/sched/sch_fq_codel.c */ #ifndef __NET_SCHED_FQ_H #define __NET_SCHED_FQ_H struct fq_tin; /** * struct fq_flow - per traffic flow queue * * @tin: owner of this flow. Used to manage collisions, i.e. when a packet * hashes to an index which points to a flow that is already owned by a * different tin the packet is destined to. In such case the implementer * must provide a fallback flow * @flowchain: can be linked to fq_tin's new_flows or old_flows. Used for DRR++ * (deficit round robin) based round robin queuing similar to the one * found in net/sched/sch_fq_codel.c * @backlogchain: can be linked to other fq_flow and fq. Used to keep track of * fat flows and efficient head-dropping if packet limit is reached * @queue: sk_buff queue to hold packets * @backlog: number of bytes pending in the queue. The number of packets can be * found in @queue.qlen * @deficit: used for DRR++ */ struct fq_flow { struct fq_tin *tin; struct list_head flowchain; struct list_head backlogchain; struct sk_buff_head queue; u32 backlog; int deficit; }; /** * struct fq_tin - a logical container of fq_flows * * Used to group fq_flows into a logical aggregate. DRR++ scheme is used to * pull interleaved packets out of the associated flows. * * @new_flows: linked list of fq_flow * @old_flows: linked list of fq_flow */ struct fq_tin { struct list_head new_flows; struct list_head old_flows; u32 backlog_bytes; u32 backlog_packets; u32 overlimit; u32 collisions; u32 flows; u32 tx_bytes; u32 tx_packets; }; /** * struct fq - main container for fair queuing purposes * * @backlogs: linked to fq_flows. Used to maintain fat flows for efficient * head-dropping when @backlog reaches @limit * @limit: max number of packets that can be queued across all flows * @backlog: number of packets queued across all flows */ struct fq { struct fq_flow *flows; struct list_head backlogs; spinlock_t lock; u32 flows_cnt; u32 perturbation; u32 limit; u32 memory_limit; u32 memory_usage; u32 quantum; u32 backlog; u32 overlimit; u32 overmemory; u32 collisions; }; typedef struct sk_buff *fq_tin_dequeue_t(struct fq *, struct fq_tin *, struct fq_flow *flow); typedef void fq_skb_free_t(struct fq *, struct fq_tin *, struct fq_flow *, struct sk_buff *); typedef struct fq_flow *fq_flow_get_default_t(struct fq *, struct fq_tin *, int idx, struct sk_buff *); #endif alue='committer'>committer
path: root/include/soc/at91/atmel-secumod.h
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authorLuis R. Rodriguez <mcgrof@kernel.org>2017-01-25 10:31:52 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-01-27 09:19:48 +0100
commit191e885a2e130e639bb0c8ee350d7047294f2ce6 (patch)
tree9bf9f9b4971df55a46e0a6750d3f6cd37bf1d9f0 /include/soc/at91/atmel-secumod.h
parent49def1853334396f948dcb4cedb9347abb318df5 (diff)
firmware: fix NULL pointer dereference in __fw_load_abort()
Since commit 5d47ec02c37ea6 ("firmware: Correct handling of fw_state_wait() return value") fw_load_abort() could be called twice and lead us to a kernel crash. This happens only when the firmware fallback mechanism (regular or custom) is used. The fallback mechanism exposes a sysfs interface for userspace to upload a file and notify the kernel when the file is loaded and ready, or to cancel an upload by echo'ing -1 into on the loading file: echo -n "-1" > /sys/$DEVPATH/loading This will call fw_load_abort(). Some distributions actually have a udev rule in place to *always* immediately cancel all firmware fallback mechanism requests (Debian), they have: $ cat /lib/udev/rules.d/50-firmware.rules # stub for immediately telling the kernel that userspace firmware loading # failed; necessary to avoid long timeouts with CONFIG_FW_LOADER_USER_HELPER=y SUBSYSTEM=="firmware", ACTION=="add", ATTR{loading}="-1 Distributions with this udev rule would run into this crash only if the fallback mechanism is used. Since most distributions disable by default using the fallback mechanism (CONFIG_FW_LOADER_USER_HELPER_FALLBACK), this would typicaly mean only 2 drivers which *require* the fallback mechanism could typically incur a crash: drivers/firmware/dell_rbu.c and the drivers/leds/leds-lp55xx-common.c driver. Distributions enabling CONFIG_FW_LOADER_USER_HELPER_FALLBACK by default are obviously more exposed to this crash. The crash happens because after commit 5b029624948d ("firmware: do not use fw_lock for fw_state protection") and subsequent fix commit 5d47ec02c37ea6 ("firmware: Correct handling of fw_state_wait() return value") a race can happen between this cancelation and the firmware fw_state_wait_timeout() being woken up after a state change with which fw_load_abort() as that calls swake_up(). Upon error fw_state_wait_timeout() will also again call fw_load_abort() and trigger a null reference. At first glance we could just fix this with a !buf check on fw_load_abort() before accessing buf->fw_st, however there is a logical issue in having a state machine used for the fallback mechanism and preventing access from it once we abort as its inside the buf (buf->fw_st). The firmware_class.c code is setting the buf to NULL to annotate an abort has occurred. Replace this mechanism by simply using the state check instead. All the other code in place already uses similar checks for aborting as well so no further changes are needed. An oops can be reproduced with the new fw_fallback.sh fallback mechanism cancellation test. Either cancelling the fallback mechanism or the custom fallback mechanism triggers a crash. mcgrof@piggy ~/linux-next/tools/testing/selftests/firmware (git::20170111-fw-fixes)$ sudo ./fw_fallback.sh ./fw_fallback.sh: timeout works ./fw_fallback.sh: firmware comparison works ./fw_fallback.sh: fallback mechanism works [ this then sits here when it is trying the cancellation test ] Kernel log: test_firmware: loading 'nope-test-firmware.bin' misc test_firmware: Direct firmware load for nope-test-firmware.bin failed with error -2 misc test_firmware: Falling back to user helper BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 IP: _request_firmware+0xa27/0xad0 PGD 0 Oops: 0000 [#1] SMP Modules linked in: test_firmware(E) ... etc ... CPU: 1 PID: 1396 Comm: fw_fallback.sh Tainted: G W E 4.10.0-rc3-next-20170111+ #30 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 task: ffff9740b27f4340 task.stack: ffffbb15c0bc8000 RIP: 0010:_request_firmware+0xa27/0xad0 RSP: 0018:ffffbb15c0bcbd10 EFLAGS: 00010246 RAX: 00000000fffffffe RBX: ffff9740afe5aa80 RCX: 0000000000000000 RDX: ffff9740b27f4340 RSI: 0000000000000283 RDI: 0000000000000000 RBP: ffffbb15c0bcbd90 R08: ffffbb15c0bcbcd8 R09: 0000000000000000 R10: 0000000894a0d4b1 R11: 000000000000008c R12: ffffffffc0312480 R13: 0000000000000005 R14: ffff9740b1c32400 R15: 00000000000003e8 FS: 00007f8604422700(0000) GS:ffff9740bfc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 000000012164c000 CR4: 00000000000006e0 Call Trace: request_firmware+0x37/0x50 trigger_request_store+0x79/0xd0 [test_firmware] dev_attr_store+0x18/0x30 sysfs_kf_write+0x37/0x40 kernfs_fop_write+0x110/0x1a0 __vfs_write+0x37/0x160 ? _cond_resched+0x1a/0x50 vfs_write+0xb5/0x1a0 SyS_write+0x55/0xc0 ? trace_do_page_fault+0x37/0xd0 entry_SYSCALL_64_fastpath+0x1e/0xad RIP: 0033:0x7f8603f49620 RSP: 002b:00007fff6287b788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055c307b110a0 RCX: 00007f8603f49620 RDX: 0000000000000016 RSI: 000055c3084d8a90 RDI: 0000000000000001 RBP: 0000000000000016 R08: 000000000000c0ff R09: 000055c3084d6336 R10: 000055c307b108b0 R11: 0000000000000246 R12: 000055c307b13c80 R13: 000055c3084d6320 R14: 0000000000000000 R15: 00007fff6287b950 Code: 9f 64 84 e8 9c 61 fe ff b8 f4 ff ff ff e9 6b f9 ff ff 48 c7 c7 40 6b 8d 84 89 45 a8 e8 43 84 18 00 49 8b be 00 03 00 00 8b 45 a8 <83> 7f 38 02 74 08 e8 6e ec ff ff 8b 45 a8 49 c7 86 00 03 00 00 RIP: _request_firmware+0xa27/0xad0 RSP: ffffbb15c0bcbd10 CR2: 0000000000000038 ---[ end trace 6d94ac339c133e6f ]--- Fixes: 5d47ec02c37e ("firmware: Correct handling of fw_state_wait() return value") Reported-and-Tested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reported-and-Tested-by: Patrick Bruenn <p.bruenn@beckhoff.com> Reported-by: Chris Wilson <chris@chris-wilson.co.uk> CC: <stable@vger.kernel.org> [3.10+] Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/soc/at91/atmel-secumod.h')