@@ -370,6 +370,8 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
result = ima_protect_xattr(dentry, xattr_name, xattr_value,
xattr_value_len);
if (result == 1) {
+ if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST))
+ return -EINVAL;
ima_reset_appraise_flags(dentry->d_inode,
(xvalue->type == EVM_IMA_XATTR_DIGSIG) ? 1 : 0);
result = 0;
@@ -57,6 +57,7 @@ enum evm_ima_xattr_type {
EVM_XATTR_HMAC,
EVM_IMA_XATTR_DIGSIG,
IMA_XATTR_DIGEST_NG,
+ IMA_XATTR_LAST
};
struct evm_ima_xattr_data {
This is a note to let you know that I have just added a patch titled ima: check xattr value length and type in the ima_inode_setxattr() to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt1. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 40b23dd007e7b7df6475096a5f7706bb43125d47 Mon Sep 17 00:00:00 2001 From: Dmitry Kasatkin <d.kasatkin@samsung.com> Date: Tue, 28 Oct 2014 13:31:22 +0200 Subject: ima: check xattr value length and type in the ima_inode_setxattr() commit a48fda9de94500a3152a56b723d0a64ae236547c upstream. ima_inode_setxattr() can be called with no value. Function does not check the length so that following command can be used to produce kernel oops: setfattr -n security.ima FOO. This patch fixes it. Changes in v3: * for stable reverted "allow setting hash only in fix or log mode" It will be a separate patch. Changes in v2: * testing validity of xattr type * allow setting hash only in fix or log mode (Mimi) [ 261.562522] BUG: unable to handle kernel NULL pointer dereference at (null) [ 261.564109] IP: [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] PGD 3112f067 PUD 42965067 PMD 0 [ 261.564109] Oops: 0000 [#1] SMP [ 261.564109] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse [ 261.564109] CPU: 0 PID: 3299 Comm: setxattr Not tainted 3.16.0-kds+ #2924 [ 261.564109] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 261.564109] task: ffff8800428c2430 ti: ffff880042be0000 task.ti: ffff880042be0000 [ 261.564109] RIP: 0010:[<ffffffff812af272>] [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] RSP: 0018:ffff880042be3d50 EFLAGS: 00010246 [ 261.564109] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000015 [ 261.564109] RDX: 0000001500000000 RSI: 0000000000000000 RDI: ffff8800375cc600 [ 261.564109] RBP: ffff880042be3d68 R08: 0000000000000000 R09: 00000000004d6256 [ 261.564109] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88002149ba00 [ 261.564109] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 261.564109] FS: 00007f6c1e219740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000 [ 261.564109] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 261.564109] CR2: 0000000000000000 CR3: 000000003b35a000 CR4: 00000000000006f0 [ 261.564109] Stack: [ 261.564109] ffff88002149ba00 ffff880042be3df8 0000000000000000 ffff880042be3d98 [ 261.564109] ffffffff812a101b ffff88002149ba00 ffff880042be3df8 0000000000000000 [ 261.564109] 0000000000000000 ffff880042be3de0 ffffffff8116d08a ffff880042be3dc8 [ 261.564109] Call Trace: [ 261.564109] [<ffffffff812a101b>] security_inode_setxattr+0x48/0x6a [ 261.564109] [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f [ 261.564109] [<ffffffff8116d1e0>] setxattr+0x122/0x16c [ 261.564109] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 261.564109] [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143 [ 261.564109] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 261.564109] [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f [ 261.564109] [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0 [ 261.564109] [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b [ 261.564109] Code: 48 89 f7 48 c7 c6 58 36 81 81 53 31 db e8 73 27 04 00 85 c0 75 28 bf 15 00 00 00 e8 8a a5 d9 ff 84 c0 75 05 83 cb ff eb 15 31 f6 <41> 80 7d 00 03 49 8b 7c 24 68 40 0f 94 c6 e8 e1 f9 ff ff 89 d8 [ 261.564109] RIP [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] RSP <ffff880042be3d50> [ 261.564109] CR2: 0000000000000000 [ 261.599998] ---[ end trace 39a89a3fc267e652 ]--- Reported-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- security/integrity/ima/ima_appraise.c | 2 ++ security/integrity/integrity.h | 1 + 2 files changed, 3 insertions(+) -- 2.1.0