{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2024-49946", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-49946", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2024-10-21T18:02:03.779Z", "updatedAt": "2026-05-11T20:42:36.068Z", "importedAt": "2026-10-24T01:57:16.009Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ppp: do not assume bh is held in ppp_channel_bridge_input()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nppp: do not assume bh is held in ppp_channel_bridge_input()\n\nNetworking receive path is usually handled from BH handler.\nHowever, some protocols need to acquire the socket lock, and\npackets might be stored in the socket backlog is the socket was\nowned by a user process.\n\nIn this case, release_sock(), __release_sock(), and sk_backlog_rcv()\nmight call the sk->sk_backlog_rcv() handler in process context.\n\nsybot caught ppp was not considering this case in\nppp_channel_bridge_input() :\n\nWARNING: inconsistent lock state\n6.11.0-rc7-syzkaller-g5f5673607153 #0 Not tainted\n--------------------------------\ninconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.\nksoftirqd/1/24 [HC0[0]:SC1[1]:HE1:SE0] takes:\n ffff0000db7f11e0 (&pch->downl){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]\n ffff0000db7f11e0 (&pch->downl){+.?.}-{2:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline]\n ffff0000db7f11e0 (&pch->downl){+.?.}-{2:2}, at: ppp_input+0x16c/0x854 drivers/net/ppp/ppp_generic.c:2304\n{SOFTIRQ-ON-W} state was registered at:\n lock_acquire+0x240/0x728 kernel/locking/lockdep.c:5759\n __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]\n _raw_spin_lock+0x48/0x60 kernel/locking/spinlock.c:154\n spin_lock include/linux/spinlock.h:351 [inline]\n ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline]\n ppp_input+0x16c/0x854 drivers/net/ppp/ppp_generic.c:2304\n pppoe_rcv_core+0xfc/0x314 drivers/net/ppp/pppoe.c:379\n sk_backlog_rcv include/net/sock.h:1111 [inline]\n __release_sock+0x1a8/0x3d8 net/core/sock.c:3004\n release_sock+0x68/0x1b8 net/core/sock.c:3558\n pppoe_sendmsg+0xc8/0x5d8 drivers/net/ppp/pppoe.c:903\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg net/socket.c:745 [inline]\n __sys_sendto+0x374/0x4f4 net/socket.c:2204\n __do_sys_sendto net/socket.c:2216 [inline]\n __se_sys_sendto net/socket.c:2212 [inline]\n __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2212\n __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]\n invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49\n el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132\n do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151\n el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712\n el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730\n el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598\nirq event stamp: 282914\n hardirqs last enabled at (282914): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]\n hardirqs last enabled at (282914): [] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194\n hardirqs last disabled at (282913): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]\n hardirqs last disabled at (282913): [] _raw_spin_lock_irqsave+0x2c/0x7c kernel/locking/spinlock.c:162\n softirqs last enabled at (282904): [] softirq_handle_end kernel/softirq.c:400 [inline]\n softirqs last enabled at (282904): [] handle_softirqs+0xa3c/0xbfc kernel/softirq.c:582\n softirqs last disabled at (282909): [] run_ksoftirqd+0x70/0x158 kernel/softirq.c:928\n\nother info that might help us debug this:\n Possible unsafe locking scenario:\n\n CPU0\n ----\n lock(&pch->downl);\n \n lock(&pch->downl);\n\n *** DEADLOCK ***\n\n1 lock held by ksoftirqd/1/24:\n #0: ffff80008f74dfa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:325\n\nstack backtrace:\nCPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.11.0-rc7-syzkaller-g5f5673607153 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024\nCall trace:\n dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:319\n show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:326\n __dump_sta\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "176dd41e8c2bd997ed3d66568a3362e69ecce99b" }, { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "635deca1800a68624f185dc1e04a8495b48cf185" }, { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "f9620e2a665aa642625bd2501282bbddff556bd7" }, { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "efe9cc0f7c0279216a5522271ec675b8288602e4" }, { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "c837f8583535f094a39386308c2ccfd92c8596cd" }, { "version": "4cf476ced45d7f12df30a68e833b263e7a2202d1", "status": "affected", "versionType": "git", "lessThan": "aec7291003df78cb71fd461d7b672912bde55807" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "5.11", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "5.11" }, { "version": "5.15.168", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.113", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.55", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.10.14", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.10.*" }, { "version": "6.11.3", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.11.*" }, { "version": "6.12", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }