CVE-2021-47197 net/mlx5e: nullify cq->dbg pointer in mlx5_debug_cq_remove()

2024-04-1018:56:33

Linux

github.com

linux

kernel

vulnerability

fix

nullify

mlx5e

debug

crash

destroy

operations

return

command

AI Score

6.5

Confidence

Low

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

net/mlx5e: nullify cq->dbg pointer in mlx5_debug_cq_remove()

Prior to this patch in case mlx5_core_destroy_cq() failed it proceeds
to rest of destroy operations. mlx5_core_destroy_cq() could be called again
by user and cause additional call of mlx5_debug_cq_remove().
cq->dbg was not nullify in previous call and cause the crash.

Fix it by nullify cq->dbg pointer after removal.

Also proceed to destroy operations only if FW return 0
for MLX5_CMD_OP_DESTROY_CQ command.

general protection fault, probably for non-canonical address 0x2000300004058: 0000 [#1] SMP PTI
CPU: 5 PID: 1228 Comm: python Not tainted 5.15.0-rc5_for_upstream_min_debug_2021_10_14_11_06 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:lockref_get+0x1/0x60
Code: 5d e9 53 ff ff ff 48 8d 7f 70 e8 0a 2e 48 00 c7 85 d0 00 00 00 02
00 00 00 c6 45 70 00 fb 5d c3 c3 cc cc cc cc cc cc cc cc 53 <48> 8b 17
48 89 fb 85 d2 75 3d 48 89 d0 bf 64 00 00 00 48 89 c1 48
RSP: 0018:ffff888137dd7a38 EFLAGS: 00010206
RAX: 0000000000000000 RBX: ffff888107d5f458 RCX: 00000000fffffffe
RDX: 000000000002c2b0 RSI: ffffffff8155e2e0 RDI: 0002000300004058
RBP: ffff888137dd7a88 R08: 0002000300004058 R09: ffff8881144a9f88
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881141d4000
R13: ffff888137dd7c68 R14: ffff888137dd7d58 R15: ffff888137dd7cc0
FS: 00007f4644f2a4c0(0000) GS:ffff8887a2d40000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b4500f4380 CR3: 0000000114f7a003 CR4: 0000000000170ea0
Call Trace:
simple_recursive_removal+0x33/0x2e0
? debugfs_remove+0x60/0x60
debugfs_remove+0x40/0x60
mlx5_debug_cq_remove+0x32/0x70 [mlx5_core]
mlx5_core_destroy_cq+0x41/0x1d0 [mlx5_core]
devx_obj_cleanup+0x151/0x330 [mlx5_ib]
? __pollwait+0xd0/0xd0
? xas_load+0x5/0x70
? xa_load+0x62/0xa0
destroy_hw_idr_uobject+0x20/0x80 [ib_uverbs]
uverbs_destroy_uobject+0x3b/0x360 [ib_uverbs]
uobj_destroy+0x54/0xa0 [ib_uverbs]
ib_uverbs_cmd_verbs+0xaf2/0x1160 [ib_uverbs]
? uverbs_finalize_object+0xd0/0xd0 [ib_uverbs]
ib_uverbs_ioctl+0xc4/0x1b0 [ib_uverbs]
__x64_sys_ioctl+0x3e4/0x8e0

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "4f7bddf8c5c0",
        "lessThan": "471c49289055",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "94b960b9deff",
        "lessThan": "2ae381570806",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "94b960b9deff",
        "lessThan": "76ded29d3fcd",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "drivers/net/ethernet/mellanox/mlx5/core/cq.c",
      "drivers/net/ethernet/mellanox/mlx5/core/debugfs.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "5.15"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "5.15",
        "versionType": "custom"
      },
      {
        "status": "unaffected",
        "version": "5.10.82",
        "versionType": "custom",
        "lessThanOrEqual": "5.10.*"
      },
      {
        "status": "unaffected",
        "version": "5.15.5",
        "versionType": "custom",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "5.16",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "drivers/net/ethernet/mellanox/mlx5/core/cq.c",
      "drivers/net/ethernet/mellanox/mlx5/core/debugfs.c"
    ],
    "defaultStatus": "affected"
  }
]