Linux Kernel up to 5.16.10 parisc sba_unmap_sg null pointer dereference

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 5.16.10. The affected element is the function sba_unmap_sg of the component parisc. The manipulation results in null pointer dereference. This vulnerability is identified as CVE-2022-48795. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.16.10. Affected is the function sba_unmap_sg of the component parisc. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: parisc: Fix data TLB miss in sba_unmap_sg Rolf Eike Beer reported the following bug: [1274934.746891] Bad Address (null pointer deref?): Code=15 (Data TLB miss fault) at addr 0000004140000018 [1274934.746891] CPU: 3 PID: 5549 Comm: cmake Not tainted 5.15.4-gentoo-parisc64 #4 [1274934.746891] Hardware name: 9000/785/C8000 [1274934.746891] [1274934.746891] YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI [1274934.746891] PSW: 00001000000001001111111000001110 Not tainted [1274934.746891] r00-03 000000ff0804fe0e 0000000040bc9bc0 00000000406760e4 0000004140000000 [1274934.746891] r04-07 0000000040b693c0 0000004140000000 000000004a2b08b0 0000000000000001 [1274934.746891] r08-11 0000000041f98810 0000000000000000 000000004a0a7000 0000000000000001 [1274934.746891] r12-15 0000000040bddbc0 0000000040c0cbc0 0000000040bddbc0 0000000040bddbc0 [1274934.746891] r16-19 0000000040bde3c0 0000000040bddbc0 0000000040bde3c0 0000000000000007 [1274934.746891] r20-23 0000000000000006 000000004a368950 0000000000000000 0000000000000001 [1274934.746891] r24-27 0000000000001fff 000000000800000e 000000004a1710f0 0000000040b693c0 [1274934.746891] r28-31 0000000000000001 0000000041f988b0 0000000041f98840 000000004a171118 [1274934.746891] sr00-03 00000000066e5800 0000000000000000 0000000000000000 00000000066e5800 [1274934.746891] sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [1274934.746891] [1274934.746891] IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000406760e8 00000000406760ec [1274934.746891] IIR: 48780030 ISR: 0000000000000000 IOR: 0000004140000018 [1274934.746891] CPU: 3 CR30: 00000040e3a9c000 CR31: ffffffffffffffff [1274934.746891] ORIG_R28: 0000000040acdd58 [1274934.746891] IAOQ[0]: sba_unmap_sg+0xb0/0x118 [1274934.746891] IAOQ[1]: sba_unmap_sg+0xb4/0x118 [1274934.746891] RP(r2): sba_unmap_sg+0xac/0x118 [1274934.746891] Backtrace: [1274934.746891] [] dma_unmap_sg_attrs+0x6c/0x70 [1274934.746891] [] scsi_dma_unmap+0x54/0x60 [1274934.746891] [] mptscsih_io_done+0x150/0xd70 [1274934.746891] [] mpt_interrupt+0x168/0xa68 [1274934.746891] [] __handle_irq_event_percpu+0xc8/0x278 [1274934.746891] [] handle_irq_event_percpu+0x3c/0xd8 [1274934.746891] [] handle_percpu_irq+0xb4/0xf0 [1274934.746891] [] generic_handle_irq+0x50/0x70 [1274934.746891] [] call_on_stack+0x18/0x24 [1274934.746891] [1274934.746891] Kernel panic - not syncing: Bad Address (null pointer deref?) The bug is caused by overrunning the sglist and incorrectly testing sg_dma_len(sglist) before nents. Normally this doesn't cause a crash, but in this case sglist crossed a page boundary. This occurs in the following code: while (sg_dma_len(sglist) && nents--) { The fix is simply to test nents first and move the decrement of nents into the loop.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2022-48795 since 07/16/2024. The exploitability is told to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 4.9.303, 4.14.268, 4.19.231, 5.4.181, 5.10.102, 5.15.25 or 5.16.11 eliminates this vulnerability. Applying the patch f23f0444ead4/de75676ee99b/867e50231c76/efccc9b0c7e2/f8f519d7df66/8c8e949ae81e/e40ae3133ed8/b7d6f44a0fa7 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.9.302
• 4.14.267
• 4.19.230
• 5.4.180
• 5.10.101
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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