{ "containers": { "cna": { "providerMetadata": { "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxdp, net: Fix use-after-free in bpf_xdp_link_release\n\nThe problem occurs between dev_get_by_index() and dev_xdp_attach_link().\nAt this point, dev_xdp_uninstall() is called. Then xdp link will not be\ndetached automatically when dev is released. But link->dev already\npoints to dev, when xdp link is released, dev will still be accessed,\nbut dev has been released.\n\ndev_get_by_index() |\nlink->dev = dev |\n | rtnl_lock()\n | unregister_netdevice_many()\n | dev_xdp_uninstall()\n | rtnl_unlock()\nrtnl_lock(); |\ndev_xdp_attach_link() |\nrtnl_unlock(); |\n | netdev_run_todo() // dev released\nbpf_xdp_link_release() |\n /* access dev. |\n use-after-free */ |\n\n[ 45.966867] BUG: KASAN: use-after-free in bpf_xdp_link_release+0x3b8/0x3d0\n[ 45.967619] Read of size 8 at addr ffff00000f9980c8 by task a.out/732\n[ 45.968297]\n[ 45.968502] CPU: 1 PID: 732 Comm: a.out Not tainted 5.13.0+ #22\n[ 45.969222] Hardware name: linux,dummy-virt (DT)\n[ 45.969795] Call trace:\n[ 45.970106] dump_backtrace+0x0/0x4c8\n[ 45.970564] show_stack+0x30/0x40\n[ 45.970981] dump_stack_lvl+0x120/0x18c\n[ 45.971470] print_address_description.constprop.0+0x74/0x30c\n[ 45.972182] kasan_report+0x1e8/0x200\n[ 45.972659] __asan_report_load8_noabort+0x2c/0x50\n[ 45.973273] bpf_xdp_link_release+0x3b8/0x3d0\n[ 45.973834] bpf_link_free+0xd0/0x188\n[ 45.974315] bpf_link_put+0x1d0/0x218\n[ 45.974790] bpf_link_release+0x3c/0x58\n[ 45.975291] __fput+0x20c/0x7e8\n[ 45.975706] ____fput+0x24/0x30\n[ 45.976117] task_work_run+0x104/0x258\n[ 45.976609] do_notify_resume+0x894/0xaf8\n[ 45.977121] work_pending+0xc/0x328\n[ 45.977575]\n[ 45.977775] The buggy address belongs to the page:\n[ 45.978369] page:fffffc00003e6600 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4f998\n[ 45.979522] flags: 0x7fffe0000000000(node=0|zone=0|lastcpupid=0x3ffff)\n[ 45.980349] raw: 07fffe0000000000 fffffc00003e6708 ffff0000dac3c010 0000000000000000\n[ 45.981309] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000\n[ 45.982259] page dumped because: kasan: bad access detected\n[ 45.982948]\n[ 45.983153] Memory state around the buggy address:\n[ 45.983753] ffff00000f997f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc\n[ 45.984645] ffff00000f998000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[ 45.985533] >ffff00000f998080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[ 45.986419] ^\n[ 45.987112] ffff00000f998100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[ 45.988006] ffff00000f998180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n[ 45.988895] ==================================================================\n[ 45.989773] Disabling lock debugging due to kernel taint\n[ 45.990552] Kernel panic - not syncing: panic_on_warn set ...\n[ 45.991166] CPU: 1 PID: 732 Comm: a.out Tainted: G B 5.13.0+ #22\n[ 45.991929] Hardware name: linux,dummy-virt (DT)\n[ 45.992448] Call trace:\n[ 45.992753] dump_backtrace+0x0/0x4c8\n[ 45.993208] show_stack+0x30/0x40\n[ 45.993627] dump_stack_lvl+0x120/0x18c\n[ 45.994113] dump_stack+0x1c/0x34\n[ 45.994530] panic+0x3a4/0x7d8\n[ 45.994930] end_report+0x194/0x198\n[ 45.995380] kasan_report+0x134/0x200\n[ 45.995850] __asan_report_load8_noabort+0x2c/0x50\n[ 45.996453] bpf_xdp_link_release+0x3b8/0x3d0\n[ 45.997007] bpf_link_free+0xd0/0x188\n[ 45.997474] bpf_link_put+0x1d0/0x218\n[ 45.997942] bpf_link_release+0x3c/0x58\n[ 45.998429] __fput+0x20c/0x7e8\n[ 45.998833] ____fput+0x24/0x30\n[ 45.999247] task_work_run+0x104/0x258\n[ 45.999731] do_notify_resume+0x894/0xaf8\n[ 46.000236] work_pending\n---truncated---" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/dev.c" ], "versions": [ { "version": "aa8d3a716b59", "lessThan": "ca9ba1de8f09", "status": "affected", "versionType": "git" }, { "version": "aa8d3a716b59", "lessThan": "a7537dc73e69", "status": "affected", "versionType": "git" }, { "version": "aa8d3a716b59", "lessThan": "5acc7d3e8d34", "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/core/dev.c" ], "versions": [ { "version": "5.9", "status": "affected" }, { "version": "0", "lessThan": "5.9", "status": "unaffected", "versionType": "custom" }, { "version": "5.10.54", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.13.6", "lessThanOrEqual": "5.13.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.14", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ca9ba1de8f09976b45ccc8e655c51c6201992139" }, { "url": "https://git.kernel.org/stable/c/a7537dc73e69ad9c0b67ad24ad3ebee954ed0af6" }, { "url": "https://git.kernel.org/stable/c/5acc7d3e8d342858405fbbc671221f676b547ce7" } ], "title": "xdp, net: Fix use-after-free in bpf_xdp_link_release", "x_generator": { "engine": "bippy-a5840b7849dd" } } }, "cveMetadata": { "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038", "cveID": "CVE-2021-47299", "requesterUserId": "gregkh@kernel.org", "serial": "1", "state": "PUBLISHED" }, "dataType": "CVE_RECORD", "dataVersion": "5.0" }