[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"repo-stars":3,"vuln-DEBIAN-CVE-2021-47544":6},{"stargazers_count":4,"fetched_at":5},7,"2026-06-04T02:53:27.892Z",{"id":7,"descriptions":8,"cisa":9,"weaknesses":10,"exploits":11,"aliases":12,"duplicate_of":9,"upstream":13,"downstream":16,"duplicates":17,"related":18,"reserved_at":9,"published_at":19,"modified_at":20,"state":9,"summary":21,"references_raw":23,"kevs":30,"epss":9,"epss_history":31,"metrics":32,"affected":39},"DEBIAN-CVE-2021-47544","In the Linux kernel, the following vulnerability has been resolved:  tcp: fix page frag corruption on page fault  Steffen reported a TCP stream corruption for HTTP requests served by the apache web-server using a cifs mount-point and memory mapping the relevant file.  The root cause is quite similar to the one addressed by commit 20eb4f29b602 (\"net: fix sk_page_frag() recursion from memory reclaim\"). Here the nested access to the task page frag is caused by a page fault on the (mmapped) user-space memory buffer coming from the cifs file.  The page fault handler performs an smb transaction on a different socket, inside the same process context. Since sk->sk_allaction for such socket does not prevent the usage for the task_frag, the nested allocation modify \"under the hood\" the page frag in use by the outer sendmsg call, corrupting the stream.  The overall relevant stack trace looks like the following:  httpd 78268 [001] 3461630.850950:      probe:tcp_sendmsg_locked:         ffffffff91461d91 tcp_sendmsg_locked+0x1         ffffffff91462b57 tcp_sendmsg+0x27         ffffffff9139814e sock_sendmsg+0x3e         ffffffffc06dfe1d smb_send_kvec+0x28         [...]         ffffffffc06cfaf8 cifs_readpages+0x213         ffffffff90e83c4b read_pages+0x6b         ffffffff90e83f31 __do_page_cache_readahead+0x1c1         ffffffff90e79e98 filemap_fault+0x788         ffffffff90eb0458 __do_fault+0x38         ffffffff90eb5280 do_fault+0x1a0         ffffffff90eb7c84 __handle_mm_fault+0x4d4         ffffffff90eb8093 handle_mm_fault+0xc3         ffffffff90c74f6d __do_page_fault+0x1ed         ffffffff90c75277 do_page_fault+0x37         ffffffff9160111e page_fault+0x1e         ffffffff9109e7b5 copyin+0x25         ffffffff9109eb40 _copy_from_iter_full+0xe0         ffffffff91462370 tcp_sendmsg_locked+0x5e0         ffffffff91462370 tcp_sendmsg_locked+0x5e0         ffffffff91462b57 tcp_sendmsg+0x27         ffffffff9139815c sock_sendmsg+0x4c         ffffffff913981f7 sock_write_iter+0x97         ffffffff90f2cc56 do_iter_readv_writev+0x156         ffffffff90f2dff0 do_iter_write+0x80         ffffffff90f2e1c3 vfs_writev+0xa3         ffffffff90f2e27c do_writev+0x5c         ffffffff90c042bb do_syscall_64+0x5b         ffffffff916000ad entry_SYSCALL_64_after_hwframe+0x65  The cifs filesystem rightfully sets sk_allocations to GFP_NOFS, we can avoid the nesting using the sk page frag for allocation lacking the __GFP_FS flag. Do not define an additional mm-helper for that, as this is strictly tied to the sk page frag usage.  v1 -> v2:  - use a stricted sk_page_frag() check instead of reordering the    code (Eric)",null,[],[],[],[14],{"_key":15},"CVE-2021-47544",[],[],[],"2024-05-24T15:15:18.983Z","2026-04-28T20:23:31.769313Z",{"cisa_kev":22,"cisa_ransomware":22,"cisa_vendor":9,"epss_severity":9,"epss_score":9,"severity":9,"severity_score":9,"severity_version":9,"severity_source":9,"severity_vector":9,"severity_status":9},false,[24],{"url":25,"sources":26,"tags":28},"https://security-tracker.debian.org/tracker/CVE-2021-47544",[27],"osv_debian",[29],"Advisory",[],[],[33],{"source":27,"cvss_v2_0":9,"cvss_v3_0":9,"cvss_v3_1":34,"cvss_v4_0":9},{"baseScore":35,"baseSeverity":9,"vectorString":36,"impactScore":37,"exploitabilityScore":38},5.9,"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",6,5.6,[40],{"ecosystem":41,"name":42,"vendor":43,"product":42,"cpe_part":9,"purl_type":44,"purl_namespace":43,"purl_name":42,"source":9,"versions":45},"Debian","linux","debian","deb",[46,52,55,56],{"version":47,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":50,"version_end_type":51,"fixed_in":9},"lt5_10_84_1",true,"ecosystem","5.10.84-1","excluding",{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9},"lt5_15_15_1","5.15.15-1",{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9},{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9}]