| 文件 | 最后提交记录 | 最后更新时间 |
|---|---|---|
eventfs: Implement eventfs dir creation functions Add eventfs_file structure which will hold the properties of the eventfs files and directories. Add following functions to create the directories in eventfs: eventfs_create_events_dir() will create the top level "events" directory within the tracefs file system. eventfs_add_subsystem_dir() creates an eventfs_file descriptor with the given name of the subsystem. eventfs_add_dir() creates an eventfs_file descriptor with the given name of the directory and attached to a eventfs_file of a subsystem. Add tracefs_inode structure to hold the inodes, flags and pointers to private data used by eventfs. Link: https://lkml.kernel.org/r/1690568452-46553-5-git-send-email-akaher@vmware.com Signed-off-by: Ajay Kaher <akaher@vmware.com> Co-developed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Tested-by: Ching-lin Yu <chinglinyu@google.com> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-lkp/202305051619.9a469a9a-yujie.liu@intel.com Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> | 3 年前 | |
eventfs: Use list_del_rcu() for SRCU protected list variable stable inclusion from stable-6.6.51 commit 05e08297c3c298d8ec28e5a5adb55840312dd87e category: bugfix issue: #IB7W7N CVE: NA Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> --------------------------------------- commit d2603279c7d645bf0d11fa253b23f1ab48fc8d3c upstream. Chi Zhiling reported: We found a null pointer accessing in tracefs[1], the reason is that the variable 'ei_child' is set to LIST_POISON1, that means the list was removed in eventfs_remove_rec. so when access the ei_child->is_freed, the panic triggered. by the way, the following script can reproduce this panic loop1 (){ while true do echo "p:kp submit_bio" > /sys/kernel/debug/tracing/kprobe_events echo "" > /sys/kernel/debug/tracing/kprobe_events done } loop2 (){ while true do tree /sys/kernel/debug/tracing/events/kprobes/ done } loop1 & loop2 [1]: [ 1147.959632][T17331] Unable to handle kernel paging request at virtual address dead000000000150 [ 1147.968239][T17331] Mem abort info: [ 1147.971739][T17331] ESR = 0x0000000096000004 [ 1147.976172][T17331] EC = 0x25: DABT (current EL), IL = 32 bits [ 1147.982171][T17331] SET = 0, FnV = 0 [ 1147.985906][T17331] EA = 0, S1PTW = 0 [ 1147.989734][T17331] FSC = 0x04: level 0 translation fault [ 1147.995292][T17331] Data abort info: [ 1147.998858][T17331] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 1148.005023][T17331] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 1148.010759][T17331] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 1148.016752][T17331] [dead000000000150] address between user and kernel address ranges [ 1148.024571][T17331] Internal error: Oops: 0000000096000004 [#1] SMP [ 1148.030825][T17331] Modules linked in: team_mode_loadbalance team nlmon act_gact cls_flower sch_ingress bonding tls macvlan dummy ib_core bridge stp llc veth amdgpu amdxcp mfd_core gpu_sched drm_exec drm_buddy radeon crct10dif_ce video drm_suballoc_helper ghash_ce drm_ttm_helper sha2_ce ttm sha256_arm64 i2c_algo_bit sha1_ce sbsa_gwdt cp210x drm_display_helper cec sr_mod cdrom drm_kms_helper binfmt_misc sg loop fuse drm dm_mod nfnetlink ip_tables autofs4 [last unloaded: tls] [ 1148.072808][T17331] CPU: 3 PID: 17331 Comm: ls Tainted: G W ------- ---- 6.6.43 #2 [ 1148.081751][T17331] Source Version: 21b3b386e948bedd29369af66f3e98ab01b1c650 [ 1148.088783][T17331] Hardware name: Greatwall GW-001M1A-FTF/GW-001M1A-FTF, BIOS KunLun BIOS V4.0 07/16/2020 [ 1148.098419][T17331] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1148.106060][T17331] pc : eventfs_iterate+0x2c0/0x398 [ 1148.111017][T17331] lr : eventfs_iterate+0x2fc/0x398 [ 1148.115969][T17331] sp : ffff80008d56bbd0 [ 1148.119964][T17331] x29: ffff80008d56bbf0 x28: ffff001ff5be2600 x27: 0000000000000000 [ 1148.127781][T17331] x26: ffff001ff52ca4e0 x25: 0000000000009977 x24: dead000000000100 [ 1148.135598][T17331] x23: 0000000000000000 x22: 000000000000000b x21: ffff800082645f10 [ 1148.143415][T17331] x20: ffff001fddf87c70 x19: ffff80008d56bc90 x18: 0000000000000000 [ 1148.151231][T17331] x17: 0000000000000000 x16: 0000000000000000 x15: ffff001ff52ca4e0 [ 1148.159048][T17331] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ 1148.166864][T17331] x11: 0000000000000000 x10: 0000000000000000 x9 : ffff8000804391d0 [ 1148.174680][T17331] x8 : 0000000180000000 x7 : 0000000000000018 x6 : 0000aaab04b92862 [ 1148.182498][T17331] x5 : 0000aaab04b92862 x4 : 0000000080000000 x3 : 0000000000000068 [ 1148.190314][T17331] x2 : 000000000000000f x1 : 0000000000007ea8 x0 : 0000000000000001 [ 1148.198131][T17331] Call trace: [ 1148.201259][T17331] eventfs_iterate+0x2c0/0x398 [ 1148.205864][T17331] iterate_dir+0x98/0x188 [ 1148.210036][T17331] __arm64_sys_getdents64+0x78/0x160 [ 1148.215161][T17331] invoke_syscall+0x78/0x108 [ 1148.219593][T17331] el0_svc_common.constprop.0+0x48/0xf0 [ 1148.224977][T17331] do_el0_svc+0x24/0x38 [ 1148.228974][T17331] el0_svc+0x40/0x168 [ 1148.232798][T17331] el0t_64_sync_handler+0x120/0x130 [ 1148.237836][T17331] el0t_64_sync+0x1a4/0x1a8 [ 1148.242182][T17331] Code: 54ffff6c f9400676 910006d6 f9000676 (b9405300) [ 1148.248955][T17331] ---[ end trace 0000000000000000 ]--- The issue is that list_del() is used on an SRCU protected list variable before the synchronization occurs. This can poison the list pointers while there is a reader iterating the list. This is simply fixed by using list_del_rcu() that is specifically made for this purpose. Link: https://lore.kernel.org/linux-trace-kernel/20240829085025.3600021-1-chizhiling@163.com/ Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/20240904131605.640d42b1@gandalf.local.home Fixes: 43aa6f97c2d03 ("eventfs: Get rid of dentry pointers without refcounts") Reported-by: Chi Zhiling <chizhiling@kylinos.cn> Tested-by: Chi Zhiling <chizhiling@kylinos.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> | 1 年前 | |
tracefs: Use generic inode RCU for synchronizing freeing stable inclusion from stable-6.6.46 commit 726f4c241e17be75a9cf6870d80cd7479dc89e8f category: bugfix issue: #IB7W7N CVE: NA Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> --------------------------------------- commit 0b6743bd60a56a701070b89fb80c327a44b7b3e2 upstream. With structure layout randomization enabled for 'struct inode' we need to avoid overlapping any of the RCU-used / initialized-only-once members, e.g. i_lru or i_sb_list to not corrupt related list traversals when making use of the rcu_head. For an unlucky structure layout of 'struct inode' we may end up with the following splat when running the ftrace selftests: [<...>] list_del corruption, ffff888103ee2cb0->next (tracefs_inode_cache+0x0/0x4e0 [slab object]) is NULL (prev is tracefs_inode_cache+0x78/0x4e0 [slab object]) [<...>] ------------[ cut here ]------------ [<...>] kernel BUG at lib/list_debug.c:54! [<...>] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [<...>] CPU: 3 PID: 2550 Comm: mount Tainted: G N 6.8.12-grsec+ #122 ed2f536ca62f28b087b90e3cc906a8d25b3ddc65 [<...>] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 [<...>] RIP: 0010:[<ffffffff84656018>] __list_del_entry_valid_or_report+0x138/0x3e0 [<...>] Code: 48 b8 99 fb 65 f2 ff ff ff ff e9 03 5c d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff e9 33 5a d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff <0f> 0b 4c 89 e9 48 89 ea 48 89 ee 48 c7 c7 60 8f dd 89 31 c0 e8 2f [<...>] RSP: 0018:fffffe80416afaf0 EFLAGS: 00010283 [<...>] RAX: 0000000000000098 RBX: ffff888103ee2cb0 RCX: 0000000000000000 [<...>] RDX: ffffffff84655fe8 RSI: ffffffff89dd8b60 RDI: 0000000000000001 [<...>] RBP: ffff888103ee2cb0 R08: 0000000000000001 R09: fffffbd0082d5f25 [<...>] R10: fffffe80416af92f R11: 0000000000000001 R12: fdf99c16731d9b6d [<...>] R13: 0000000000000000 R14: ffff88819ad4b8b8 R15: 0000000000000000 [<...>] RBX: tracefs_inode_cache+0x0/0x4e0 [slab object] [<...>] RDX: __list_del_entry_valid_or_report+0x108/0x3e0 [<...>] RSI: __func__.47+0x4340/0x4400 [<...>] RBP: tracefs_inode_cache+0x0/0x4e0 [slab object] [<...>] RSP: process kstack fffffe80416afaf0+0x7af0/0x8000 [mount 2550 2550] [<...>] R09: kasan shadow of process kstack fffffe80416af928+0x7928/0x8000 [mount 2550 2550] [<...>] R10: process kstack fffffe80416af92f+0x792f/0x8000 [mount 2550 2550] [<...>] R14: tracefs_inode_cache+0x78/0x4e0 [slab object] [<...>] FS: 00006dcb380c1840(0000) GS:ffff8881e0600000(0000) knlGS:0000000000000000 [<...>] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [<...>] CR2: 000076ab72b30e84 CR3: 000000000b088004 CR4: 0000000000360ef0 shadow CR4: 0000000000360ef0 [<...>] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [<...>] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [<...>] ASID: 0003 [<...>] Stack: [<...>] ffffffff818a2315 00000000f5c856ee ffffffff896f1840 ffff888103ee2cb0 [<...>] ffff88812b6b9750 0000000079d714b6 fffffbfff1e9280b ffffffff8f49405f [<...>] 0000000000000001 0000000000000000 ffff888104457280 ffffffff8248b392 [<...>] Call Trace: [<...>] <TASK> [<...>] [<ffffffff818a2315>] ? lock_release+0x175/0x380 fffffe80416afaf0 [<...>] [<ffffffff8248b392>] list_lru_del+0x152/0x740 fffffe80416afb48 [<...>] [<ffffffff8248ba93>] list_lru_del_obj+0x113/0x280 fffffe80416afb88 [<...>] [<ffffffff8940fd19>] ? _atomic_dec_and_lock+0x119/0x200 fffffe80416afb90 [<...>] [<ffffffff8295b244>] iput_final+0x1c4/0x9a0 fffffe80416afbb8 [<...>] [<ffffffff8293a52b>] dentry_unlink_inode+0x44b/0xaa0 fffffe80416afbf8 [<...>] [<ffffffff8293fefc>] __dentry_kill+0x23c/0xf00 fffffe80416afc40 [<...>] [<ffffffff8953a85f>] ? __this_cpu_preempt_check+0x1f/0xa0 fffffe80416afc48 [<...>] [<ffffffff82949ce5>] ? shrink_dentry_list+0x1c5/0x760 fffffe80416afc70 [<...>] [<ffffffff82949b71>] ? shrink_dentry_list+0x51/0x760 fffffe80416afc78 [<...>] [<ffffffff82949da8>] shrink_dentry_list+0x288/0x760 fffffe80416afc80 [<...>] [<ffffffff8294ae75>] shrink_dcache_sb+0x155/0x420 fffffe80416afcc8 [<...>] [<ffffffff8953a7c3>] ? debug_smp_processor_id+0x23/0xa0 fffffe80416afce0 [<...>] [<ffffffff8294ad20>] ? do_one_tree+0x140/0x140 fffffe80416afcf8 [<...>] [<ffffffff82997349>] ? do_remount+0x329/0xa00 fffffe80416afd18 [<...>] [<ffffffff83ebf7a1>] ? security_sb_remount+0x81/0x1c0 fffffe80416afd38 [<...>] [<ffffffff82892096>] reconfigure_super+0x856/0x14e0 fffffe80416afd70 [<...>] [<ffffffff815d1327>] ? ns_capable_common+0xe7/0x2a0 fffffe80416afd90 [<...>] [<ffffffff82997436>] do_remount+0x416/0xa00 fffffe80416afdd0 [<...>] [<ffffffff829b2ba4>] path_mount+0x5c4/0x900 fffffe80416afe28 [<...>] [<ffffffff829b25e0>] ? finish_automount+0x13a0/0x13a0 fffffe80416afe60 [<...>] [<ffffffff82903812>] ? user_path_at_empty+0xb2/0x140 fffffe80416afe88 [<...>] [<ffffffff829b2ff5>] do_mount+0x115/0x1c0 fffffe80416afeb8 [<...>] [<ffffffff829b2ee0>] ? path_mount+0x900/0x900 fffffe80416afed8 [<...>] [<ffffffff8272461c>] ? __kasan_check_write+0x1c/0xa0 fffffe80416afee0 [<...>] [<ffffffff829b31cf>] __do_sys_mount+0x12f/0x280 fffffe80416aff30 [<...>] [<ffffffff829b36cd>] __x64_sys_mount+0xcd/0x2e0 fffffe80416aff70 [<...>] [<ffffffff819f8818>] ? syscall_trace_enter+0x218/0x380 fffffe80416aff88 [<...>] [<ffffffff8111655e>] x64_sys_call+0x5d5e/0x6720 fffffe80416affa8 [<...>] [<ffffffff8952756d>] do_syscall_64+0xcd/0x3c0 fffffe80416affb8 [<...>] [<ffffffff8100119b>] entry_SYSCALL_64_safe_stack+0x4c/0x87 fffffe80416affe8 [<...>] </TASK> [<...>] <PTREGS> [<...>] RIP: 0033:[<00006dcb382ff66a>] vm_area_struct[mount 2550 2550 file 6dcb38225000-6dcb3837e000 22 55(read|exec|mayread|mayexec)]+0x0/0xb8 [userland map] [<...>] Code: 48 8b 0d 29 18 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f6 17 0d 00 f7 d8 64 89 01 48 [<...>] RSP: 002b:0000763d68192558 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [<...>] RAX: ffffffffffffffda RBX: 00006dcb38433264 RCX: 00006dcb382ff66a [<...>] RDX: 000017c3e0d11210 RSI: 000017c3e0d1a5a0 RDI: 000017c3e0d1ae70 [<...>] RBP: 000017c3e0d10fb0 R08: 000017c3e0d11260 R09: 00006dcb383d1be0 [<...>] R10: 000000000020002e R11: 0000000000000246 R12: 0000000000000000 [<...>] R13: 000017c3e0d1ae70 R14: 000017c3e0d11210 R15: 000017c3e0d10fb0 [<...>] RBX: vm_area_struct[mount 2550 2550 file 6dcb38433000-6dcb38434000 5b 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RCX: vm_area_struct[mount 2550 2550 file 6dcb38225000-6dcb3837e000 22 55(read|exec|mayread|mayexec)]+0x0/0xb8 [userland map] [<...>] RDX: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RSI: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RDI: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RBP: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RSP: vm_area_struct[mount 2550 2550 anon 763d68173000-763d68195000 7ffffffdd 100133(read|write|mayread|maywrite|growsdown|account)]+0x0/0xb8 [userland map] [<...>] R08: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R09: vm_area_struct[mount 2550 2550 file 6dcb383d1000-6dcb383d3000 1cd 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R13: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R14: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R15: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] </PTREGS> [<...>] Modules linked in: [<...>] ---[ end trace 0000000000000000 ]--- The list debug message as well as RBX's symbolic value point out that the object in question was allocated from 'tracefs_inode_cache' and that the list's '->next' member is at offset 0. Dumping the layout of the relevant parts of 'struct tracefs_inode' gives the following: struct tracefs_inode { union { struct inode { struct list_head { struct list_head * next; /* 0 8 */ struct list_head * prev; /* 8 8 */ } i_lru; [...] } vfs_inode; struct callback_head { void (*func)(struct callback_head *); /* 0 8 */ struct callback_head * next; /* 8 8 */ } rcu; }; [...] }; Above shows that 'vfs_inode.i_lru' overlaps with 'rcu' which will destroy the 'i_lru' list as soon as the 'rcu' member gets used, e.g. in call_rcu() or later when calling the RCU callback. This will disturb concurrent list traversals as well as object reuse which assumes these list heads will keep their integrity. For reproduction, the following diff manually overlays 'i_lru' with 'rcu' as, otherwise, one would require some good portion of luck for gambling an unlucky RANDSTRUCT seed: --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -629,6 +629,7 @@ struct inode { umode_t i_mode; unsigned short i_opflags; kuid_t i_uid; + struct list_head i_lru; /* inode LRU list */ kgid_t i_gid; unsigned int i_flags; @@ -690,7 +691,6 @@ struct inode { u16 i_wb_frn_avg_time; u16 i_wb_frn_history; #endif - struct list_head i_lru; /* inode LRU list */ struct list_head i_sb_list; struct list_head i_wb_list; /* backing dev writeback list */ union { The tracefs inode does not need to supply its own RCU delayed destruction of its inode. The inode code itself offers both a "destroy_inode()" callback that gets called when the last reference of the inode is released, and the "free_inode()" which is called after a RCU synchronization period from the "destroy_inode()". The tracefs code can unlink the inode from its list in the destroy_inode() callback, and the simply free it from the free_inode() callback. This should provide the same protection. Link: https://lore.kernel.org/all/20240807115143.45927-3-minipli@grsecurity.net/ Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Cc: Ilkka =?utf-8?b?TmF1bGFww6TDpA==?= <digirigawa@gmail.com> Link: https://lore.kernel.org/20240807185402.61410544@gandalf.local.home Fixes: baa23a8d4360 ("tracefs: Reset permissions on remount if permissions are options") Reported-by: Mathias Krause <minipli@grsecurity.net> Reported-by: Brad Spengler <spender@grsecurity.net> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> | 1 年前 | |
tracefs: Use generic inode RCU for synchronizing freeing stable inclusion from stable-6.6.46 commit 726f4c241e17be75a9cf6870d80cd7479dc89e8f category: bugfix issue: #IB7W7N CVE: NA Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> --------------------------------------- commit 0b6743bd60a56a701070b89fb80c327a44b7b3e2 upstream. With structure layout randomization enabled for 'struct inode' we need to avoid overlapping any of the RCU-used / initialized-only-once members, e.g. i_lru or i_sb_list to not corrupt related list traversals when making use of the rcu_head. For an unlucky structure layout of 'struct inode' we may end up with the following splat when running the ftrace selftests: [<...>] list_del corruption, ffff888103ee2cb0->next (tracefs_inode_cache+0x0/0x4e0 [slab object]) is NULL (prev is tracefs_inode_cache+0x78/0x4e0 [slab object]) [<...>] ------------[ cut here ]------------ [<...>] kernel BUG at lib/list_debug.c:54! [<...>] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [<...>] CPU: 3 PID: 2550 Comm: mount Tainted: G N 6.8.12-grsec+ #122 ed2f536ca62f28b087b90e3cc906a8d25b3ddc65 [<...>] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 [<...>] RIP: 0010:[<ffffffff84656018>] __list_del_entry_valid_or_report+0x138/0x3e0 [<...>] Code: 48 b8 99 fb 65 f2 ff ff ff ff e9 03 5c d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff e9 33 5a d9 fc cc 48 b8 99 fb 65 f2 ff ff ff ff <0f> 0b 4c 89 e9 48 89 ea 48 89 ee 48 c7 c7 60 8f dd 89 31 c0 e8 2f [<...>] RSP: 0018:fffffe80416afaf0 EFLAGS: 00010283 [<...>] RAX: 0000000000000098 RBX: ffff888103ee2cb0 RCX: 0000000000000000 [<...>] RDX: ffffffff84655fe8 RSI: ffffffff89dd8b60 RDI: 0000000000000001 [<...>] RBP: ffff888103ee2cb0 R08: 0000000000000001 R09: fffffbd0082d5f25 [<...>] R10: fffffe80416af92f R11: 0000000000000001 R12: fdf99c16731d9b6d [<...>] R13: 0000000000000000 R14: ffff88819ad4b8b8 R15: 0000000000000000 [<...>] RBX: tracefs_inode_cache+0x0/0x4e0 [slab object] [<...>] RDX: __list_del_entry_valid_or_report+0x108/0x3e0 [<...>] RSI: __func__.47+0x4340/0x4400 [<...>] RBP: tracefs_inode_cache+0x0/0x4e0 [slab object] [<...>] RSP: process kstack fffffe80416afaf0+0x7af0/0x8000 [mount 2550 2550] [<...>] R09: kasan shadow of process kstack fffffe80416af928+0x7928/0x8000 [mount 2550 2550] [<...>] R10: process kstack fffffe80416af92f+0x792f/0x8000 [mount 2550 2550] [<...>] R14: tracefs_inode_cache+0x78/0x4e0 [slab object] [<...>] FS: 00006dcb380c1840(0000) GS:ffff8881e0600000(0000) knlGS:0000000000000000 [<...>] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [<...>] CR2: 000076ab72b30e84 CR3: 000000000b088004 CR4: 0000000000360ef0 shadow CR4: 0000000000360ef0 [<...>] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [<...>] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [<...>] ASID: 0003 [<...>] Stack: [<...>] ffffffff818a2315 00000000f5c856ee ffffffff896f1840 ffff888103ee2cb0 [<...>] ffff88812b6b9750 0000000079d714b6 fffffbfff1e9280b ffffffff8f49405f [<...>] 0000000000000001 0000000000000000 ffff888104457280 ffffffff8248b392 [<...>] Call Trace: [<...>] <TASK> [<...>] [<ffffffff818a2315>] ? lock_release+0x175/0x380 fffffe80416afaf0 [<...>] [<ffffffff8248b392>] list_lru_del+0x152/0x740 fffffe80416afb48 [<...>] [<ffffffff8248ba93>] list_lru_del_obj+0x113/0x280 fffffe80416afb88 [<...>] [<ffffffff8940fd19>] ? _atomic_dec_and_lock+0x119/0x200 fffffe80416afb90 [<...>] [<ffffffff8295b244>] iput_final+0x1c4/0x9a0 fffffe80416afbb8 [<...>] [<ffffffff8293a52b>] dentry_unlink_inode+0x44b/0xaa0 fffffe80416afbf8 [<...>] [<ffffffff8293fefc>] __dentry_kill+0x23c/0xf00 fffffe80416afc40 [<...>] [<ffffffff8953a85f>] ? __this_cpu_preempt_check+0x1f/0xa0 fffffe80416afc48 [<...>] [<ffffffff82949ce5>] ? shrink_dentry_list+0x1c5/0x760 fffffe80416afc70 [<...>] [<ffffffff82949b71>] ? shrink_dentry_list+0x51/0x760 fffffe80416afc78 [<...>] [<ffffffff82949da8>] shrink_dentry_list+0x288/0x760 fffffe80416afc80 [<...>] [<ffffffff8294ae75>] shrink_dcache_sb+0x155/0x420 fffffe80416afcc8 [<...>] [<ffffffff8953a7c3>] ? debug_smp_processor_id+0x23/0xa0 fffffe80416afce0 [<...>] [<ffffffff8294ad20>] ? do_one_tree+0x140/0x140 fffffe80416afcf8 [<...>] [<ffffffff82997349>] ? do_remount+0x329/0xa00 fffffe80416afd18 [<...>] [<ffffffff83ebf7a1>] ? security_sb_remount+0x81/0x1c0 fffffe80416afd38 [<...>] [<ffffffff82892096>] reconfigure_super+0x856/0x14e0 fffffe80416afd70 [<...>] [<ffffffff815d1327>] ? ns_capable_common+0xe7/0x2a0 fffffe80416afd90 [<...>] [<ffffffff82997436>] do_remount+0x416/0xa00 fffffe80416afdd0 [<...>] [<ffffffff829b2ba4>] path_mount+0x5c4/0x900 fffffe80416afe28 [<...>] [<ffffffff829b25e0>] ? finish_automount+0x13a0/0x13a0 fffffe80416afe60 [<...>] [<ffffffff82903812>] ? user_path_at_empty+0xb2/0x140 fffffe80416afe88 [<...>] [<ffffffff829b2ff5>] do_mount+0x115/0x1c0 fffffe80416afeb8 [<...>] [<ffffffff829b2ee0>] ? path_mount+0x900/0x900 fffffe80416afed8 [<...>] [<ffffffff8272461c>] ? __kasan_check_write+0x1c/0xa0 fffffe80416afee0 [<...>] [<ffffffff829b31cf>] __do_sys_mount+0x12f/0x280 fffffe80416aff30 [<...>] [<ffffffff829b36cd>] __x64_sys_mount+0xcd/0x2e0 fffffe80416aff70 [<...>] [<ffffffff819f8818>] ? syscall_trace_enter+0x218/0x380 fffffe80416aff88 [<...>] [<ffffffff8111655e>] x64_sys_call+0x5d5e/0x6720 fffffe80416affa8 [<...>] [<ffffffff8952756d>] do_syscall_64+0xcd/0x3c0 fffffe80416affb8 [<...>] [<ffffffff8100119b>] entry_SYSCALL_64_safe_stack+0x4c/0x87 fffffe80416affe8 [<...>] </TASK> [<...>] <PTREGS> [<...>] RIP: 0033:[<00006dcb382ff66a>] vm_area_struct[mount 2550 2550 file 6dcb38225000-6dcb3837e000 22 55(read|exec|mayread|mayexec)]+0x0/0xb8 [userland map] [<...>] Code: 48 8b 0d 29 18 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f6 17 0d 00 f7 d8 64 89 01 48 [<...>] RSP: 002b:0000763d68192558 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [<...>] RAX: ffffffffffffffda RBX: 00006dcb38433264 RCX: 00006dcb382ff66a [<...>] RDX: 000017c3e0d11210 RSI: 000017c3e0d1a5a0 RDI: 000017c3e0d1ae70 [<...>] RBP: 000017c3e0d10fb0 R08: 000017c3e0d11260 R09: 00006dcb383d1be0 [<...>] R10: 000000000020002e R11: 0000000000000246 R12: 0000000000000000 [<...>] R13: 000017c3e0d1ae70 R14: 000017c3e0d11210 R15: 000017c3e0d10fb0 [<...>] RBX: vm_area_struct[mount 2550 2550 file 6dcb38433000-6dcb38434000 5b 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RCX: vm_area_struct[mount 2550 2550 file 6dcb38225000-6dcb3837e000 22 55(read|exec|mayread|mayexec)]+0x0/0xb8 [userland map] [<...>] RDX: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RSI: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RDI: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RBP: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] RSP: vm_area_struct[mount 2550 2550 anon 763d68173000-763d68195000 7ffffffdd 100133(read|write|mayread|maywrite|growsdown|account)]+0x0/0xb8 [userland map] [<...>] R08: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R09: vm_area_struct[mount 2550 2550 file 6dcb383d1000-6dcb383d3000 1cd 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R13: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R14: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] R15: vm_area_struct[mount 2550 2550 anon 17c3e0d0f000-17c3e0d31000 17c3e0d0f 100033(read|write|mayread|maywrite|account)]+0x0/0xb8 [userland map] [<...>] </PTREGS> [<...>] Modules linked in: [<...>] ---[ end trace 0000000000000000 ]--- The list debug message as well as RBX's symbolic value point out that the object in question was allocated from 'tracefs_inode_cache' and that the list's '->next' member is at offset 0. Dumping the layout of the relevant parts of 'struct tracefs_inode' gives the following: struct tracefs_inode { union { struct inode { struct list_head { struct list_head * next; /* 0 8 */ struct list_head * prev; /* 8 8 */ } i_lru; [...] } vfs_inode; struct callback_head { void (*func)(struct callback_head *); /* 0 8 */ struct callback_head * next; /* 8 8 */ } rcu; }; [...] }; Above shows that 'vfs_inode.i_lru' overlaps with 'rcu' which will destroy the 'i_lru' list as soon as the 'rcu' member gets used, e.g. in call_rcu() or later when calling the RCU callback. This will disturb concurrent list traversals as well as object reuse which assumes these list heads will keep their integrity. For reproduction, the following diff manually overlays 'i_lru' with 'rcu' as, otherwise, one would require some good portion of luck for gambling an unlucky RANDSTRUCT seed: --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -629,6 +629,7 @@ struct inode { umode_t i_mode; unsigned short i_opflags; kuid_t i_uid; + struct list_head i_lru; /* inode LRU list */ kgid_t i_gid; unsigned int i_flags; @@ -690,7 +691,6 @@ struct inode { u16 i_wb_frn_avg_time; u16 i_wb_frn_history; #endif - struct list_head i_lru; /* inode LRU list */ struct list_head i_sb_list; struct list_head i_wb_list; /* backing dev writeback list */ union { The tracefs inode does not need to supply its own RCU delayed destruction of its inode. The inode code itself offers both a "destroy_inode()" callback that gets called when the last reference of the inode is released, and the "free_inode()" which is called after a RCU synchronization period from the "destroy_inode()". The tracefs code can unlink the inode from its list in the destroy_inode() callback, and the simply free it from the free_inode() callback. This should provide the same protection. Link: https://lore.kernel.org/all/20240807115143.45927-3-minipli@grsecurity.net/ Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Cc: Ilkka =?utf-8?b?TmF1bGFww6TDpA==?= <digirigawa@gmail.com> Link: https://lore.kernel.org/20240807185402.61410544@gandalf.local.home Fixes: baa23a8d4360 ("tracefs: Reset permissions on remount if permissions are options") Reported-by: Mathias Krause <minipli@grsecurity.net> Reported-by: Brad Spengler <spender@grsecurity.net> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: zhangshuqi <zhangshuqi3@huawei.com> | 1 年前 |
| 文件 | 最后提交记录 | 最后更新时间 |
|---|---|---|
| 3 年前 | ||
| 1 年前 | ||
| 1 年前 | ||
| 1 年前 |