diff --git a/patches.suse/cifs-fix-use-after-free-caused-by-invalid-pointer-ho.patch b/patches.suse/cifs-fix-use-after-free-caused-by-invalid-pointer-ho.patch new file mode 100644 index 0000000..ee3b21a --- /dev/null +++ b/patches.suse/cifs-fix-use-after-free-caused-by-invalid-pointer-ho.patch @@ -0,0 +1,131 @@ +From 153695d36ead0ccc4d0256953c751cabf673e621 Mon Sep 17 00:00:00 2001 +From: Zeng Heng +Date: Thu, 27 Oct 2022 20:45:28 +0800 +Subject: [PATCH] cifs: fix use-after-free caused by invalid pointer `hostname` +References: bsc#1208971 +Git-commit: 153695d36ead0ccc4d0256953c751cabf673e621 +Patch-mainline: v6.1 + +`hostname` needs to be set as null-pointer after free in +`cifs_put_tcp_session` function, or when `cifsd` thread attempts +to resolve hostname and reconnect the host, the thread would deref +the invalid pointer. + +Here is one of practical backtrace examples as reference: + +Task 477 +--------------------------- + do_mount + path_mount + do_new_mount + vfs_get_tree + smb3_get_tree + smb3_get_tree_common + cifs_smb3_do_mount + cifs_mount + mount_put_conns + cifs_put_tcp_session + --> kfree(server->hostname) + +cifsd +--------------------------- + kthread + cifs_demultiplex_thread + cifs_reconnect + reconn_set_ipaddr_from_hostname + --> if (!server->hostname) + --> if (server->hostname[0] == '\0') // !! UAF fault here + +CIFS: VFS: cifs_mount failed w/return code = -112 +mount error(112): Host is down +BUG: KASAN: use-after-free in reconn_set_ipaddr_from_hostname+0x2ba/0x310 +Read of size 1 at addr ffff888108f35380 by task cifsd/480 +CPU: 2 PID: 480 Comm: cifsd Not tainted 6.1.0-rc2-00106-gf705792f89dd-dirty #25 +Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 +Call Trace: + + dump_stack_lvl+0x68/0x85 + print_report+0x16c/0x4a3 + kasan_report+0x95/0x190 + reconn_set_ipaddr_from_hostname+0x2ba/0x310 + __cifs_reconnect.part.0+0x241/0x800 + cifs_reconnect+0x65f/0xb60 + cifs_demultiplex_thread+0x1570/0x2570 + kthread+0x2c5/0x380 + ret_from_fork+0x22/0x30 + +Allocated by task 477: + kasan_save_stack+0x1e/0x40 + kasan_set_track+0x21/0x30 + __kasan_kmalloc+0x7e/0x90 + __kmalloc_node_track_caller+0x52/0x1b0 + kstrdup+0x3b/0x70 + cifs_get_tcp_session+0xbc/0x19b0 + mount_get_conns+0xa9/0x10c0 + cifs_mount+0xdf/0x1970 + cifs_smb3_do_mount+0x295/0x1660 + smb3_get_tree+0x352/0x5e0 + vfs_get_tree+0x8e/0x2e0 + path_mount+0xf8c/0x1990 + do_mount+0xee/0x110 + __x64_sys_mount+0x14b/0x1f0 + do_syscall_64+0x3b/0x90 + entry_SYSCALL_64_after_hwframe+0x63/0xcd +Freed by task 477: + kasan_save_stack+0x1e/0x40 + kasan_set_track+0x21/0x30 + kasan_save_free_info+0x2a/0x50 + __kasan_slab_free+0x10a/0x190 + __kmem_cache_free+0xca/0x3f0 + cifs_put_tcp_session+0x30c/0x450 + cifs_mount+0xf95/0x1970 + cifs_smb3_do_mount+0x295/0x1660 + smb3_get_tree+0x352/0x5e0 + vfs_get_tree+0x8e/0x2e0 + path_mount+0xf8c/0x1990 + do_mount+0xee/0x110 + __x64_sys_mount+0x14b/0x1f0 + do_syscall_64+0x3b/0x90 + entry_SYSCALL_64_after_hwframe+0x63/0xcd +The buggy address belongs to the object at ffff888108f35380 + which belongs to the cache kmalloc-16 of size 16 +The buggy address is located 0 bytes inside of + 16-byte region [ffff888108f35380, ffff888108f35390) +The buggy address belongs to the physical page: +page:00000000333f8e58 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888108f350e0 pfn:0x108f35 +flags: 0x200000000000200(slab|node=0|zone=2) +raw: 0200000000000200 0000000000000000 dead000000000122 ffff8881000423c0 +raw: ffff888108f350e0 000000008080007a 00000001ffffffff 0000000000000000 +page dumped because: kasan: bad access detected +Memory state around the buggy address: + ffff888108f35280: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc + ffff888108f35300: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc +>ffff888108f35380: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc + ^ + ffff888108f35400: fa fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc + ffff888108f35480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc + +Fixes: 7be3248f3139 ("cifs: To match file servers, make sure the server hostname matches") +Signed-off-by: Zeng Heng +Reviewed-by: Paulo Alcantara (SUSE) +Signed-off-by: Steve French +Signed-off-by: Oscar Salvador +--- + fs/cifs/connect.c | 1 + + 1 file changed, 1 insertion(+) + +diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c +index ffb291579bb9..1cc47dd3b4d6 100644 +--- a/fs/cifs/connect.c ++++ b/fs/cifs/connect.c +@@ -1584,6 +1584,7 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect) + server->session_key.response = NULL; + server->session_key.len = 0; + kfree(server->hostname); ++ server->hostname = NULL; + + task = xchg(&server->tsk, NULL); + if (task) +-- +2.35.3 + diff --git a/series.conf b/series.conf index 1f6a877..ab95bb5 100644 --- a/series.conf +++ b/series.conf @@ -23041,6 +23041,7 @@ patches.suse/kcm-avoid-potential-race-in-kcm_tx_work.patch patches.suse/io_uring-af_unix-defer-registered-files-gc-to-io_uri.patch patches.suse/net-sched-fix-race-condition-in-qdisc_graft.patch + patches.suse/cifs-fix-use-after-free-caused-by-invalid-pointer-ho.patch patches.suse/Bluetooth-L2CAP-Fix-use-after-free-caused-by-l2cap_r.patch patches.suse/Bluetooth-L2CAP-Fix-accepting-connection-request-for.patch patches.suse/Bluetooth-L2CAP-Fix-attempting-to-access-uninitializ.patch