{"vulnerability": "CVE-2024-47716", "sightings": [{"uuid": "d590bd04-bee7-4770-b8fb-d7b9ed07080e", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2024-47716", "type": "published-proof-of-concept", "source": "https://t.me/cvedetector/8473", "content": "{\n  \"Source\": \"CVE FEED\",\n  \"Title\": \"CVE-2024-47716 - Raspberry Pi ARM VFP Use-After-Free Memory Corruption\", \n  \"Content\": \"CVE ID : CVE-2024-47716 \nPublished : Oct. 21, 2024, 12:15 p.m. | 41\u00a0minutes ago \nDescription : In the Linux kernel, the following vulnerability has been resolved:  \n  \nARM: 9410/1: vfp: Use asm volatile in fmrx/fmxr macros  \n  \nFloating point instructions in userspace can crash some arm kernels  \nbuilt with clang/LLD 17.0.6:  \n  \n    BUG: unsupported FP instruction in kernel mode  \n    FPEXC == 0xc0000780  \n    Internal error: Oops - undefined instruction: 0 [#1] ARM  \n    CPU: 0 PID: 196 Comm: vfp-reproducer Not tainted 6.10.0 #1  \n    Hardware name: BCM2835  \n    PC is at vfp_support_entry+0xc8/0x2cc  \n    LR is at do_undefinstr+0xa8/0x250  \n    pc : []    lr : []    psr: a0000013  \n    sp : dc8d1f68  ip : 60000013  fp : bedea19c  \n    r10: ec532b17  r9 : 00000010  r8 : 0044766c  \n    r7 : c0000780  r6 : ec532b17  r5 : c1c13800  r4 : dc8d1fb0  \n    r3 : c10072c4  r2 : c0101c88  r1 : ec532b17  r0 : 0044766c  \n    Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none  \n    Control: 00c5387d  Table: 0251c008  DAC: 00000051  \n    Register r0 information: non-paged memory  \n    Register r1 information: vmalloc memory  \n    Register r2 information: non-slab/vmalloc memory  \n    Register r3 information: non-slab/vmalloc memory  \n    Register r4 information: 2-page vmalloc region  \n    Register r5 information: slab kmalloc-cg-2k  \n    Register r6 information: vmalloc memory  \n    Register r7 information: non-slab/vmalloc memory  \n    Register r8 information: non-paged memory  \n    Register r9 information: zero-size pointer  \n    Register r10 information: vmalloc memory  \n    Register r11 information: non-paged memory  \n    Register r12 information: non-paged memory  \n    Process vfp-reproducer (pid: 196, stack limit = 0x61aaaf8b)  \n    Stack: (0xdc8d1f68 to 0xdc8d2000)  \n    1f60:                   0000081f b6f69300 0000000f c10073f4 c10072c4 dc8d1fb0  \n    1f80: ec532b17 0c532b17 0044766c b6f9ccd8 00000000 c010a80c 00447670 60000010  \n    1fa0: ffffffff c1c13800 00c5387d c0100f10 b6f68af8 00448fc0 00000000 bedea188  \n    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c  \n    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff 00000000 00000000  \n    Call trace:  \n    [] (vfp_support_entry) from [] (do_undefinstr+0xa8/0x250)  \n    [] (do_undefinstr) from [] (__und_usr+0x70/0x80)  \n    Exception stack(0xdc8d1fb0 to 0xdc8d1ff8)  \n    1fa0:                                     b6f68af8 00448fc0 00000000 bedea188  \n    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c  \n    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff  \n    Code: 0a000061 e3877202 e594003c e3a09010 (eef16a10)  \n    ---[ end trace 0000000000000000 ]---  \n    Kernel panic - not syncing: Fatal exception in interrupt  \n    ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---  \n  \nThis is a minimal userspace reproducer on a Raspberry Pi Zero W:  \n  \n    #include   \n    #include   \n  \n    int main(void)  \n    {  \n            double v = 1.0;  \n            printf(\"%fn\", NAN + *(volatile double *)&v);  \n            return 0;  \n    }  \n  \nAnother way to consistently trigger the oops is:  \n  \n    calvin@raspberry-pi-zero-w ~$ python -c \"import json\"  \n  \nThe bug reproduces only when the kernel is built with DYNAMIC_DEBUG=n,  \nbecause the pr_debug() calls act as barriers even when not activated.  \n  \nThis is the output from the same kernel source built with the same  \ncompiler and DYNAMIC_DEBUG=y, where the userspace reproducer works as  \nexpected:  \n  \n    VFP: bounce: trigger ec532b17 fpexc c0000780  \n    VFP: emulate: INST=0xee377b06 SCR=0x00000000  \n    VFP: bounce: trigger eef1fa10 fpexc c0000780  \n    VFP: emulate: INST=0xeeb40b40 SCR=0x00000000  \n    VFP: raising exceptions 30000000  \n  \n    calvin@raspberry-pi-zero-w ~$ ./vfp-reproducer  \n    nan  \n  \nCrudely grepping for vmsr/vmrs instruct[...]", "creation_timestamp": "2024-10-21T15:10:01.000000Z"}]}