CVE-2024-41065

In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries: Whitelist dtl slub object for copying to userspace Reading the dispatch trace log from /sys/kernel/debug/powerpc/dtl/cpu-* results in a BUG() when the config CONFIG_HARDENED_USERCOPY is enabled as shown below. kernel BUG at mm/usercopy.c:102! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: xfs libcrc32c dm_service_time sd_mod t10_pi sg ibmvfc scsi_transport_fc ibmveth pseries_wdt dm_multipath dm_mirror dm_region_hash dm_log dm_mod fuse CPU: 27 PID: 1815 Comm: python3 Not tainted 6.10.0-rc3 #85 Hardware name: IBM,9040-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_042) hv:phyp pSeries NIP: c0000000005d23d4 LR: c0000000005d23d0 CTR: 00000000006ee6f8 REGS: c000000120c078c0 TRAP: 0700 Not tainted (6.10.0-rc3) MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 2828220f XER: 0000000e CFAR: c0000000001fdc80 IRQMASK: 0 [ ... GPRs omitted ... ] NIP [c0000000005d23d4] usercopy_abort+0x78/0xb0 LR [c0000000005d23d0] usercopy_abort+0x74/0xb0 Call Trace: usercopy_abort+0x74/0xb0 (unreliable) __check_heap_object+0xf8/0x120 check_heap_object+0x218/0x240 __check_object_size+0x84/0x1a4 dtl_file_read+0x17c/0x2c4 full_proxy_read+0x8c/0x110 vfs_read+0xdc/0x3a0 ksys_read+0x84/0x144 system_call_exception+0x124/0x330 system_call_vectored_common+0x15c/0x2ec --- interrupt: 3000 at 0x7fff81f3ab34 Commit 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0") requires that only whitelisted areas in slab/slub objects can be copied to userspace when usercopy hardening is enabled using CONFIG_HARDENED_USERCOPY. Dtl contains hypervisor dispatch events which are expected to be read by privileged users. Hence mark this safe for user access. Specify useroffset=0 and usersize=DISPATCH_LOG_BYTES to whitelist the entire object.

It was discovered that the CIFS network file system implementation in the Linux kernel did not properly validate certain SMB messages, leading to an out-of-bounds read vulnerability. An attacker could use this to cause a denial of service or possibly expose sensitive information. Supraja Sridhara, Benedict Schlüter, Mark Kuhne, Andrin Bertschi, and Shweta Shinde discovered that the Confidential Computing framework in the Linux kernel for x86 platforms did not properly handle 32-bit emulation on TDX and SEV. An attacker with access to the VMM could use this to cause a denial of service or possibly execute arbitrary code.