{"id":"DEBIAN-CVE-2024-41048","details":"In the Linux kernel, the following vulnerability has been resolved:  skmsg: Skip zero length skb in sk_msg_recvmsg  When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch platform, the following kernel panic occurs:    [...]   Oops[#1]:   CPU: 22 PID: 2824 Comm: test_progs Tainted: G           OE  6.10.0-rc2+ #18   Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018      ... ...      ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560     ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0    CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)    PRMD: 0000000c (PPLV0 +PIE +PWE)    EUEN: 00000007 (+FPE +SXE +ASXE -BTE)    ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)   ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)    BADV: 0000000000000040    PRID: 0014c011 (Loongson-64bit, Loongson-3C5000)   Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack   Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...)   Stack : ...   Call Trace:   [\u003c9000000004162774\u003e] copy_page_to_iter+0x74/0x1c0   [\u003c90000000048bf6c0\u003e] sk_msg_recvmsg+0x120/0x560   [\u003c90000000049f2b90\u003e] tcp_bpf_recvmsg_parser+0x170/0x4e0   [\u003c90000000049aae34\u003e] inet_recvmsg+0x54/0x100   [\u003c900000000481ad5c\u003e] sock_recvmsg+0x7c/0xe0   [\u003c900000000481e1a8\u003e] __sys_recvfrom+0x108/0x1c0   [\u003c900000000481e27c\u003e] sys_recvfrom+0x1c/0x40   [\u003c9000000004c076ec\u003e] do_syscall+0x8c/0xc0   [\u003c9000000003731da4\u003e] handle_syscall+0xc4/0x160   Code: ...   ---[ end trace 0000000000000000 ]---   Kernel panic - not syncing: Fatal exception   Kernel relocated by 0x3510000    .text @ 0x9000000003710000    .data @ 0x9000000004d70000    .bss  @ 0x9000000006469400   ---[ end Kernel panic - not syncing: Fatal exception ]---   [...]  This crash happens every time when running sockmap_skb_verdict_shutdown subtest in sockmap_basic.  This crash is because a NULL pointer is passed to page_address() in the sk_msg_recvmsg(). Due to the different implementations depending on the architecture, page_address(NULL) will trigger a panic on Loongarch platform but not on x86 platform. So this bug was hidden on x86 platform for a while, but now it is exposed on Loongarch platform. The root cause is that a zero length skb (skb-\u003elen == 0) was put on the queue.  This zero length skb is a TCP FIN packet, which was sent by shutdown(), invoked in test_sockmap_skb_verdict_shutdown():  \tshutdown(p1, SHUT_WR);  In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no page is put to this sge (see sg_set_page in sg_set_page), but this empty sge is queued into ingress_msg list.  And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it to kmap_local_page() and to page_address(), then kernel panics.  To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(), if copy is zero, that means it's a zero length skb, skip invoking copy_page_to_iter(). We are using the EFAULT return triggered by copy_page_to_iter to check for is_fin in tcp_bpf.c.","modified":"2026-09-15T09:02:57.495311156Z","published":"2024-07-29T15:15:13.103Z","upstream":["CVE-2024-41048"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-41048"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.106-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-41048.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.9.10-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-41048.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.9.10-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-41048.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}