{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: mcast: wait for previous gc cycles when removing port\n\nsyzbot hit a use-after-free[1] which is caused because the bridge doesn't\nmake sure that all previous garbage has been collected when removing a\nport. What happens is:\n      CPU 1                   CPU 2\n start gc cycle           remove port\n                         acquire gc lock first\n wait for lock\n                         call br_multicasg_gc() directly\n acquire lock now but    free port\n the port can be freed\n while grp timers still\n running\n\nMake sure all previous gc cycles have finished by using flush_work before\nfreeing the port.\n\n[1]\n  BUG: KASAN: slab-use-after-free in br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861\n  Read of size 8 at addr ffff888071d6d000 by task syz.5.1232/9699\n\n  CPU: 1 PID: 9699 Comm: syz.5.1232 Not tainted 6.10.0-rc5-syzkaller-00021-g24ca36a562d6 #0\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024\n  Call Trace:\n   <IRQ>\n   __dump_stack lib/dump_stack.c:88 [inline]\n   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114\n   print_address_description mm/kasan/report.c:377 [inline]\n   print_report+0xc3/0x620 mm/kasan/report.c:488\n   kasan_report+0xd9/0x110 mm/kasan/report.c:601\n   br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861\n   call_timer_fn+0x1a3/0x610 kernel/time/timer.c:1792\n   expire_timers kernel/time/timer.c:1843 [inline]\n   __run_timers+0x74b/0xaf0 kernel/time/timer.c:2417\n   __run_timer_base kernel/time/timer.c:2428 [inline]\n   __run_timer_base kernel/time/timer.c:2421 [inline]\n   run_timer_base+0x111/0x190 kernel/time/timer.c:2437"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "net/bridge/br_multicast.c"
               ],
               "versions": [
                  {
                     "version": "e12cec65b554",
                     "lessThan": "1e16828020c6",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e12cec65b554",
                     "lessThan": "0d8b26e10e68",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e12cec65b554",
                     "lessThan": "e3145ca904fa",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e12cec65b554",
                     "lessThan": "b2f794b168cf",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "e12cec65b554",
                     "lessThan": "92c4ee25208d",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "net/bridge/br_multicast.c"
               ],
               "versions": [
                  {
                     "version": "5.10",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.10",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.165",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.1.105",
                     "lessThanOrEqual": "6.1.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.6.46",
                     "lessThanOrEqual": "6.6.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.10.5",
                     "lessThanOrEqual": "6.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.11",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/1e16828020c674b3be85f52685e8b80f9008f50f"
            },
            {
               "url": "https://git.kernel.org/stable/c/0d8b26e10e680c01522d7cc14abe04c3265a928f"
            },
            {
               "url": "https://git.kernel.org/stable/c/e3145ca904fa8dbfd1a5bf0187905bc117b0efce"
            },
            {
               "url": "https://git.kernel.org/stable/c/b2f794b168cf560682ff976b255aa6d29d14a658"
            },
            {
               "url": "https://git.kernel.org/stable/c/92c4ee25208d0f35dafc3213cdf355fbe449e078"
            }
         ],
         "title": "net: bridge: mcast: wait for previous gc cycles when removing port",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-44934",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}