7.8

CVE-2022-48925

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

RDMA/cma: Do not change route.addr.src_addr outside state checks

If the state is not idle then resolve_prepare_src() should immediately
fail and no change to global state should happen. However, it
unconditionally overwrites the src_addr trying to build a temporary any
address.

For instance if the state is already RDMA_CM_LISTEN then this will corrupt
the src_addr and would cause the test in cma_cancel_operation():

           if (cma_any_addr(cma_src_addr(id_priv)) && !id_priv->cma_dev)

Which would manifest as this trace from syzkaller:

  BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26
  Read of size 8 at addr ffff8881546491e0 by task syz-executor.1/32204

  CPU: 1 PID: 32204 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  Call Trace:
   __dump_stack lib/dump_stack.c:79 [inline]
   dump_stack+0x141/0x1d7 lib/dump_stack.c:120
   print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
   __kasan_report mm/kasan/report.c:399 [inline]
   kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
   __list_add_valid+0x93/0xa0 lib/list_debug.c:26
   __list_add include/linux/list.h:67 [inline]
   list_add_tail include/linux/list.h:100 [inline]
   cma_listen_on_all drivers/infiniband/core/cma.c:2557 [inline]
   rdma_listen+0x787/0xe00 drivers/infiniband/core/cma.c:3751
   ucma_listen+0x16a/0x210 drivers/infiniband/core/ucma.c:1102
   ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
   vfs_write+0x28e/0xa30 fs/read_write.c:603
   ksys_write+0x1ee/0x250 fs/read_write.c:658
   do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
   entry_SYSCALL_64_after_hwframe+0x44/0xae

This is indicating that an rdma_id_private was destroyed without doing
cma_cancel_listens().

Instead of trying to re-use the src_addr memory to indirectly create an
any address derived from the dst build one explicitly on the stack and
bind to that as any other normal flow would do. rdma_bind_addr() will copy
it over the src_addr once it knows the state is valid.

This is similar to commit bc0bdc5afaa7 ("RDMA/cma: Do not change
route.addr.src_addr.ss_family")
Data is provided by the National Vulnerability Database (NVD)
LinuxLinux Kernel Version >= 5.10 < 5.10.103
LinuxLinux Kernel Version >= 5.11 < 5.15.26
LinuxLinux Kernel Version >= 5.16 < 5.16.12
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.03% 0.071
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 7.8 1.8 5.9
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.