CVE-2024-50165

In the Linux kernel, the following vulnerability has been resolved:

bpf: Preserve param->string when parsing mount options

In bpf_parse_param(), keep the value of param->string intact so it can be freed later. Otherwise, the kmalloc area pointed to by param->string will be leaked as shown below:

unreferenced object 0xffff888118c46d20 (size 8): comm new_name, pid 12109, jiffies 4295580214 hex dump (first 8 bytes): 61 6e 79 00 38 c9 5c 7e any.8.~ backtrace (crc e1b7f876): [<00000000c6848ac7>] kmemleak_alloc+0x4b/0x80 [<00000000de9f7d00>] __kmalloc_node_track_caller_noprof+0x36e/0x4a0 [<000000003e29b886>] memdup_user+0x32/0xa0 [<0000000007248326>] strndup_user+0x46/0x60 [<0000000035b3dd29>] __x64_sys_fsconfig+0x368/0x3d0 [<0000000018657927>] x64_sys_call+0xff/0x9f0 [<00000000c0cabc95>] do_syscall_64+0x3b/0xc0 [<000000002f331597>] entry_SYSCALL_64_after_hwframe+0x4b/0x53

Weakness

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/1f97c03f43fadc407de5b5cb01c07755053e1c22
• https://git.kernel.org/stable/c/5d7a0a426540319327309035509cb768a2f5c2c4