| { |
| "containers": { |
| "cna": { |
| "providerMetadata": { |
| "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038" |
| }, |
| "descriptions": [ |
| { |
| "lang": "en", |
| "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nibmvnic: fix race between xmit and reset\n\nThere is a race between reset and the transmit paths that can lead to\nibmvnic_xmit() accessing an scrq after it has been freed in the reset\npath. It can result in a crash like:\n\n\tKernel attempted to read user page (0) - exploit attempt? (uid: 0)\n\tBUG: Kernel NULL pointer dereference on read at 0x00000000\n\tFaulting instruction address: 0xc0080000016189f8\n\tOops: Kernel access of bad area, sig: 11 [#1]\n\t...\n\tNIP [c0080000016189f8] ibmvnic_xmit+0x60/0xb60 [ibmvnic]\n\tLR [c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\tCall Trace:\n\t[c008000001618f08] ibmvnic_xmit+0x570/0xb60 [ibmvnic] (unreliable)\n\t[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\t[c000000000c9cfcc] sch_direct_xmit+0xec/0x330\n\t[c000000000bfe640] __dev_xmit_skb+0x3a0/0x9d0\n\t[c000000000c00ad4] __dev_queue_xmit+0x394/0x730\n\t[c008000002db813c] __bond_start_xmit+0x254/0x450 [bonding]\n\t[c008000002db8378] bond_start_xmit+0x40/0xc0 [bonding]\n\t[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\t[c000000000c00ca4] __dev_queue_xmit+0x564/0x730\n\t[c000000000cf97e0] neigh_hh_output+0xd0/0x180\n\t[c000000000cfa69c] ip_finish_output2+0x31c/0x5c0\n\t[c000000000cfd244] __ip_queue_xmit+0x194/0x4f0\n\t[c000000000d2a3c4] __tcp_transmit_skb+0x434/0x9b0\n\t[c000000000d2d1e0] __tcp_retransmit_skb+0x1d0/0x6a0\n\t[c000000000d2d984] tcp_retransmit_skb+0x34/0x130\n\t[c000000000d310e8] tcp_retransmit_timer+0x388/0x6d0\n\t[c000000000d315ec] tcp_write_timer_handler+0x1bc/0x330\n\t[c000000000d317bc] tcp_write_timer+0x5c/0x200\n\t[c000000000243270] call_timer_fn+0x50/0x1c0\n\t[c000000000243704] __run_timers.part.0+0x324/0x460\n\t[c000000000243894] run_timer_softirq+0x54/0xa0\n\t[c000000000ea713c] __do_softirq+0x15c/0x3e0\n\t[c000000000166258] __irq_exit_rcu+0x158/0x190\n\t[c000000000166420] irq_exit+0x20/0x40\n\t[c00000000002853c] timer_interrupt+0x14c/0x2b0\n\t[c000000000009a00] decrementer_common_virt+0x210/0x220\n\t--- interrupt: 900 at plpar_hcall_norets_notrace+0x18/0x2c\n\nThe immediate cause of the crash is the access of tx_scrq in the following\nsnippet during a reset, where the tx_scrq can be either NULL or an address\nthat will soon be invalid:\n\n\tibmvnic_xmit()\n\t{\n\t\t...\n\t\ttx_scrq = adapter->tx_scrq[queue_num];\n\t\ttxq = netdev_get_tx_queue(netdev, queue_num);\n\t\tind_bufp = &tx_scrq->ind_buf;\n\n\t\tif (test_bit(0, &adapter->resetting)) {\n\t\t...\n\t}\n\nBut beyond that, the call to ibmvnic_xmit() itself is not safe during a\nreset and the reset path attempts to avoid this by stopping the queue in\nibmvnic_cleanup(). However just after the queue was stopped, an in-flight\nibmvnic_complete_tx() could have restarted the queue even as the reset is\nprogressing.\n\nSince the queue was restarted we could get a call to ibmvnic_xmit() which\ncan then access the bad tx_scrq (or other fields).\n\nWe cannot however simply have ibmvnic_complete_tx() check the ->resetting\nbit and skip starting the queue. This can race at the \"back-end\" of a good\nreset which just restarted the queue but has not cleared the ->resetting\nbit yet. If we skip restarting the queue due to ->resetting being true,\nthe queue would remain stopped indefinitely potentially leading to transmit\ntimeouts.\n\nIOW ->resetting is too broad for this purpose. Instead use a new flag\nthat indicates whether or not the queues are active. Only the open/\nreset paths control when the queues are active. ibmvnic_complete_tx()\nand others wake up the queue only if the queue is marked active.\n\nSo we will have:\n\tA. reset/open thread in ibmvnic_cleanup() and __ibmvnic_open()\n\n\t\t->resetting = true\n\t\t->tx_queues_active = false\n\t\tdisable tx queues\n\t\t...\n\t\t->tx_queues_active = true\n\t\tstart tx queues\n\n\tB. Tx interrupt in ibmvnic_complete_tx():\n\n\t\tif (->tx_queues_active)\n\t\t\tnetif_wake_subqueue();\n\nTo ensure that ->tx_queues_active and state of the queues are consistent,\nwe need a lock which:\n\n\t- must also be taken in the interrupt path (ibmvnic_complete_tx())\n\t- shared across the multiple\n---truncated---" |
| } |
| ], |
| "affected": [ |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "unaffected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "drivers/net/ethernet/ibm/ibmvnic.c", |
| "drivers/net/ethernet/ibm/ibmvnic.h" |
| ], |
| "versions": [ |
| { |
| "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", |
| "lessThan": "1bd58abf595b6cf1ba6dd47ec887c4c009155fc9", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", |
| "lessThan": "475f9cce98b63bc145b4efa66fa51175d4cb345f", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", |
| "lessThan": "8507c6ade73cdbbbda5c3d31d67f52f2e1cf03fe", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", |
| "lessThan": "4219196d1f662cb10a462eb9e076633a3fc31a15", |
| "status": "affected", |
| "versionType": "git" |
| } |
| ] |
| }, |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "affected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "drivers/net/ethernet/ibm/ibmvnic.c", |
| "drivers/net/ethernet/ibm/ibmvnic.h" |
| ], |
| "versions": [ |
| { |
| "version": "5.4", |
| "status": "affected" |
| }, |
| { |
| "version": "0", |
| "lessThan": "5.4", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.15.33", |
| "lessThanOrEqual": "5.15.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.16.19", |
| "lessThanOrEqual": "5.16.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.17.2", |
| "lessThanOrEqual": "5.17.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.18", |
| "lessThanOrEqual": "*", |
| "status": "unaffected", |
| "versionType": "original_commit_for_fix" |
| } |
| ] |
| } |
| ], |
| "cpeApplicability": [ |
| { |
| "nodes": [ |
| { |
| "operator": "OR", |
| "negate": false, |
| "cpeMatch": [ |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.4", |
| "versionEndExcluding": "5.15.33" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.4", |
| "versionEndExcluding": "5.16.19" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.4", |
| "versionEndExcluding": "5.17.2" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "5.4", |
| "versionEndExcluding": "5.18" |
| } |
| ] |
| } |
| ] |
| } |
| ], |
| "references": [ |
| { |
| "url": "https://git.kernel.org/stable/c/1bd58abf595b6cf1ba6dd47ec887c4c009155fc9" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/475f9cce98b63bc145b4efa66fa51175d4cb345f" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/8507c6ade73cdbbbda5c3d31d67f52f2e1cf03fe" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/4219196d1f662cb10a462eb9e076633a3fc31a15" |
| } |
| ], |
| "title": "ibmvnic: fix race between xmit and reset", |
| "x_generator": { |
| "engine": "bippy-1.2.0" |
| } |
| } |
| }, |
| "cveMetadata": { |
| "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038", |
| "cveID": "CVE-2022-49201", |
| "requesterUserId": "gregkh@kernel.org", |
| "serial": "1", |
| "state": "PUBLISHED" |
| }, |
| "dataType": "CVE_RECORD", |
| "dataVersion": "5.0" |
| } |
