Answer in brief
CVE-2024-56693 records a High severity (CVSS 7.8) vulnerability in brd: defer automatic disk creation until module initialization succeeds. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <41219c147df8bbd6591f59af5d695fb6c9a1cbff || >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <259bf925583ec9e3781df778cadf00594095090d || >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <410896624db639500f24f46478b4bfa05c76bf56 || >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <c0c2744cd2939ec5999c51dbaf2af16886548b7b || >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <63dfd728b30f79495dacc886127695a379805152 || >=7f9b348cb5e94259acdcbafbcaed55d3bb515304 <826cc42adf44930a633d11a5993676d85ddb0842 | 41219c147df8bbd6591f59af5d695fb6c9a1cbff, 259bf925583ec9e3781df778cadf00594095090d, 410896624db639500f24f46478b4bfa05c76bf56, c0c2744cd2939ec5999c51dbaf2af16886548b7b, 63dfd728b30f79495dacc886127695a379805152, 826cc42adf44930a633d11a5993676d85ddb0842 |
| Linux/Linuxgeneric | 5.14 | Not reported |
Published upstream
Dec 28, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: brd: defer automatic disk creation until module initialization succeeds My colleague Wupeng found the following problems during fault injection: BUG: unable to handle page fault for address: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Call Trace: <TASK> blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() is calling loop_add() after __register_blkdev() succeeds and is ignoring disk_add() failure from loop_add(), for loop_add() failure is not fatal and successfully created disks are already visible to bdev_open(). brd_init() is currently calling brd_alloc() before __register_blkdev() succeeds and is releasing successfully created disks when brd_init() returns an error. This can cause UAF for the latter two case: case 1: T1: modprobe brd brd_init brd_alloc(0) // success add_disk disk_scan_partitions bdev_file_open_by_dev // alloc file fput // won't free until back to userspace brd_alloc(1) // failed since mem alloc error inject // error path for modprobe will release code segment // back to userspace __fput blkdev_release bdev_release blkdev_put_whole bdev->bd_disk->fops->release // fops is freed now, UAF! case 2: T1: T2: modprobe brd brd_init brd_alloc(0) // success open(/dev/ram0) brd_alloc(1) // fail // error path for modprobe close(/dev/ram0) ... /* UAF! */ bdev->bd_disk->fops->release Fix this problem by following what loop_init() does. Besides, reintroduce brd_devices_mutex to help serialize modifications to brd_list.
Quoted source text, attributed separately from HOL analysis.