{"id":"AZL-52070","summary":"CVE-2024-50073 affecting package kernel for versions less than 6.6.64.2-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: n_gsm: Fix use-after-free in gsm_cleanup_mux\n\nBUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x77b/0x7b0\ndrivers/tty/n_gsm.c:3160 [n_gsm]\nRead of size 8 at addr ffff88815fe99c00 by task poc/3379\nCPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56\nHardware name: VMware, Inc. VMware Virtual Platform/440BX\nDesktop Reference Platform, BIOS 6.00 11/12/2020\nCall Trace:\n \u003cTASK\u003e\n gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]\n __pfx_gsm_cleanup_mux+0x10/0x10 drivers/tty/n_gsm.c:3124 [n_gsm]\n __pfx_sched_clock_cpu+0x10/0x10 kernel/sched/clock.c:389\n update_load_avg+0x1c1/0x27b0 kernel/sched/fair.c:4500\n __pfx_min_vruntime_cb_rotate+0x10/0x10 kernel/sched/fair.c:846\n __rb_insert_augmented+0x492/0xbf0 lib/rbtree.c:161\n gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]\n _raw_spin_lock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107\n __pfx_gsmld_ioctl+0x10/0x10 drivers/tty/n_gsm.c:3822 [n_gsm]\n ktime_get+0x5e/0x140 kernel/time/timekeeping.c:195\n ldsem_down_read+0x94/0x4e0 arch/x86/include/asm/atomic64_64.h:79\n __pfx_ldsem_down_read+0x10/0x10 drivers/tty/tty_ldsem.c:338\n __pfx_do_vfs_ioctl+0x10/0x10 fs/ioctl.c:805\n tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818\n\nAllocated by task 65:\n gsm_data_alloc.constprop.0+0x27/0x190 drivers/tty/n_gsm.c:926 [n_gsm]\n gsm_send+0x2c/0x580 drivers/tty/n_gsm.c:819 [n_gsm]\n gsm1_receive+0x547/0xad0 drivers/tty/n_gsm.c:3038 [n_gsm]\n gsmld_receive_buf+0x176/0x280 drivers/tty/n_gsm.c:3609 [n_gsm]\n tty_ldisc_receive_buf+0x101/0x1e0 drivers/tty/tty_buffer.c:391\n tty_port_default_receive_buf+0x61/0xa0 drivers/tty/tty_port.c:39\n flush_to_ldisc+0x1b0/0x750 drivers/tty/tty_buffer.c:445\n process_scheduled_works+0x2b0/0x10d0 kernel/workqueue.c:3229\n worker_thread+0x3dc/0x950 kernel/workqueue.c:3391\n kthread+0x2a3/0x370 kernel/kthread.c:389\n ret_from_fork+0x2d/0x70 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:257\n\nFreed by task 3367:\n kfree+0x126/0x420 mm/slub.c:4580\n gsm_cleanup_mux+0x36c/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]\n gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]\n tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818\n\n[Analysis]\ngsm_msg on the tx_ctrl_list or tx_data_list of gsm_mux\ncan be freed by multi threads through ioctl,which leads\nto the occurrence of uaf. Protect it by gsm tx lock.","modified":"2026-04-01T05:26:31.842379Z","published":"2024-10-29T01:15:04Z","upstream":["CVE-2024-50073"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-50073"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.64.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-52070.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}