CVE-2024-56534 isofs: avoid memory leak in iocharset
A memory leak in the Linux kernel's isofs filesystem allows local attackers to exhaust system memory, potentially causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-56534?
CVE-2024-56534 is a medium-severity memory corruption vulnerability in Linux kernel, published on 27 Dec 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
isofs: avoid memory leak in iocharset
A memleak was found as below:
unreferenced object 0xffff0000d10164d8 (size 8): comm "pool-udisksd", pid 108217, jiffies 4295408555 hex dump (first 8 bytes): 75 74 66 38 00 cc cc cc utf8.... backtrace (crc de430d31): [<ffff800081046e6c>] kmemleak_alloc+0xb8/0xc8 [<ffff8000803e6c3c>] __kmalloc_node_track_caller_noprof+0x380/0x474 [<ffff800080363b74>] kstrdup+0x70/0xfc [<ffff80007bb3c6a4>] isofs_parse_param+0x228/0x2c0 [isofs] [<ffff8000804d7f68>] vfs_parse_fs_param+0xf4/0x164 [<ffff8000804d8064>] vfs_parse_fs_string+0x8c/0xd4 [<ffff8000804d815c>] vfs_parse_monolithic_sep+0xb0/0xfc [<ffff8000804d81d8>] generic_parse_monolithic+0x30/0x3c [<ffff8000804d8bfc>] parse_monolithic_mount_data+0x40/0x4c [<ffff8000804b6a64>] path_mount+0x6c4/0x9ec [<ffff8000804b6e38>] do_mount+0xac/0xc4 [<ffff8000804b7494>] __arm64_sys_mount+0x16c/0x2b0 [<ffff80008002b8dc>] invoke_syscall+0x7c/0x104 [<ffff80008002ba44>] el0_svc_common.constprop.1+0xe0/0x104 [<ffff80008002ba94>] do_el0_svc+0x2c/0x38 [<ffff800081041108>] el0_svc+0x3c/0x1b8
The opt->iocharset is freed inside the isofs_fill_super function, But there may be situations where it's not possible to enter this function.
For example, in the get_tree_bdev_flags function,when encountering the situation where "Can't mount, would change RO state," In such a case, isofs_fill_super will not have the opportunity to be called,which means that opt->iocharset will not have the chance to be freed,ultimately leading to a memory leak.
Let's move the memory freeing of opt->iocharset into isofs_free_fc function.
Weakness: CWE-401
Which versions are affected by CVE-2024-56534?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-56534?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2024-56534 being exploited?
There is no known exploitation of CVE-2024-56534 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-56534, DEBIAN-CVE-2024-56534, GHSA-pm64-f9ff-xc6w, UBUNTU-CVE-2024-56534.