cbcvebase.
CVE-2021-47238
published 2024-05-21

CVE-2021-47238: In the Linux kernel, the following vulnerability has been resolved: net: ipv4: fix memory leak in ip_mc_add1_src BUG: memory leak unreferenced object…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.24%
14.7th percentile
In the Linux kernel, the following vulnerability has been resolved: net: ipv4: fix memory leak in ip_mc_add1_src BUG: memory leak unreferenced object 0xffff888101bc4c00 (size 32): comm "syz-executor527", pid 360, jiffies 4294807421 (age 19.329s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 01 00 00 00 00 00 00 00 ac 14 14 bb 00 00 02 00 ................ backtrace: [] kmalloc include/linux/slab.h:558 [inline] [] kzalloc include/linux/slab.h:688 [inline] [] ip_mc_add1_src net/ipv4/igmp.c:1971 [inline] [] ip_mc_add_src+0x95f/0xdb0 net/ipv4/igmp.c:2095 [] ip_mc_source+0x84c/0xea0 net/ipv4/igmp.c:2416 [] do_ip_setsockopt net/ipv4/ip_sockglue.c:1294 [inline] [] ip_setsockopt+0x114b/0x30c0 net/ipv4/ip_sockglue.c:1423 [] raw_setsockopt+0x13d/0x170 net/ipv4/raw.c:857 [] __sys_setsockopt+0x158/0x270 net/socket.c:2117 [] __do_sys_setsockopt net/socket.c:2128 [inline] [] __se_sys_setsockopt net/socket.c:2125 [inline] [] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2125 [] do_syscall_64+0x40/0x80 arch/x86/entry/common.c:47 [] entry_SYSCALL_64_after_hwframe+0x44/0xae In commit 24803f38a5c0 ("igmp: do not remove igmp souce list info when set link down"), the ip_mc_clear_src() in ip_mc_destroy_dev() was removed, because it was also called in igmpv3_clear_delrec(). Rough callgraph: inetdev_destroy -> ip_mc_destroy_dev -> igmpv3_clear_delrec -> ip_mc_clear_src -> RCU_INIT_POINTER(dev->ip_ptr, NULL) However, ip_mc_clear_src() called in igmpv3_clear_delrec() doesn't release in_dev->mc_list->sources. And RCU_INIT_POINTER() assigns the NULL to dev->ip_ptr. As a result, in_dev cannot be obtained through inetdev_by_index() and then in_dev->mc_list->sources cannot be released by ip_mc_del1_src() in the sock_close. Rough call sequence goes like: sock_close -> __sock_release -> inet_release -> ip_mc_drop_socket -> inetdev_by_index -> ip_mc_leave_src -> ip_mc_del_src -> ip_mc_del1_src So we still need to call ip_mc_clear_src() in ip_mc_des

Affected

26 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux——
linuxlinux——
linuxlinux——
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < 0dc13e75507faa17ac9f7562b4ef7bf8fcd784220dc13e75507faa17ac9f7562b4ef7bf8fcd78422
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < 6cff57eea3347f79f1867cc53e1093b6614138d86cff57eea3347f79f1867cc53e1093b6614138d8
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < 1e28018b5c83d5073f74a6fb72eabe8370b2f5011e28018b5c83d5073f74a6fb72eabe8370b2f501
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < 3dd2aeac2e9624cff9fa634710837e4f2e3527583dd2aeac2e9624cff9fa634710837e4f2e352758
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < ac31cc837cafb57a271babad8ccffbf733caa076ac31cc837cafb57a271babad8ccffbf733caa076
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < 77de6ee73f54a9a89c0afa0bf4c53b239aa9953a77de6ee73f54a9a89c0afa0bf4c53b239aa9953a
linuxlinux>= 24803f38a5c0b6c57ed800b47e695f9ce474bc3a < d8e2973029b8b2ce477b564824431f3385c77083d8e2973029b8b2ce477b564824431f3385c77083
linuxlinux>= 3.16.42 < 3.173.17
linuxlinux>= 3.2.87 < 3.33.3
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 3.16.42 < 3.173.17
linuxlinux_kernel>= 3.2.87 < 3.33.3
linuxlinux_kernel>= 4.10 < 4.14.2384.14.238
linuxlinux_kernel>= 4.15 < 4.19.1964.19.196
linuxlinux_kernel>= 4.20 < 5.4.1285.4.128
linuxlinux_kernel>= 4.9 < 4.9.2744.9.274
linuxlinux_kernel>= 5.11 < 5.12.135.12.13

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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