The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learningThere is no fixed version for RHEL:8
bpftool
.
Note: Versions mentioned in the description apply only to the upstream bpftool
package and not the bpftool
package as distributed by RHEL
.
See How to fix?
for RHEL:8
relevant fixed versions and status.
In the Linux kernel, the following vulnerability has been resolved:
null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'
Writing 'power' and 'submit_queues' concurrently will trigger kernel panic:
Test script:
modprobe null_blk nr_devices=0 mkdir -p /sys/kernel/config/nullb/nullb0 while true; do echo 1 > submit_queues; echo 4 > submit_queues; done & while true; do echo 1 > power; echo 0 > power; done
Test result:
BUG: kernel NULL pointer dereference, address: 0000000000000148 Oops: 0000 [#1] PREEMPT SMP RIP: 0010:__lock_acquire+0x41d/0x28f0 Call Trace: <TASK> lock_acquire+0x121/0x450 down_write+0x5f/0x1d0 simple_recursive_removal+0x12f/0x5c0 blk_mq_debugfs_unregister_hctxs+0x7c/0x100 blk_mq_update_nr_hw_queues+0x4a3/0x720 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_submit_queues_store+0x79/0xf0 [null_blk] configfs_write_iter+0x119/0x1e0 vfs_write+0x326/0x730 ksys_write+0x74/0x150
This is because del_gendisk() can concurrent with blk_mq_update_nr_hw_queues():
nullb_device_power_store nullb_apply_submit_queues null_del_dev del_gendisk nullb_update_nr_hw_queues if (!dev->nullb) // still set while gendisk is deleted return 0 blk_mq_update_nr_hw_queues dev->nullb = NULL
Fix this problem by resuing the global mutex to protect nullb_device_power_store() and nullb_update_nr_hw_queues() from configfs.