kernel/linux.git/security, branch v4.19.165

ima: Don't modify file descriptor mode on the fly

2020-12-30T10:26:12+00:00

commit 207cdd565dfc95a0a5185263a567817b7ebf5467 upstream. Commit a408e4a86b36b ("ima: open a new file instance if no read permissions") already introduced a second open to measure a file when the original file descriptor does not allow it. However, it didn't remove the existing method of changing the mode of the original file descriptor, which is still necessary if the current process does not have enough privileges to open a new one. Changing the mode isn't really an option, as the filesystem might need to do preliminary steps to make the read possible. Thus, this patch removes the code and keeps the second open as the only option to measure a file when it is unreadable with the original file descriptor. Cc: # 4.20.x: 0014cc04e8ec0 ima: Set file->f_mode Fixes: 2fe5d6def1672 ("ima: integrity appraisal extension") Signed-off-by: Roberto Sassu Reviewed-by: Christoph Hellwig Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

selinux: fix inode_doinit_with_dentry() LABEL_INVALID error handling

2020-12-30T10:25:51+00:00

[ Upstream commit 200ea5a2292dc444a818b096ae6a32ba3caa51b9 ] A previous fix, commit 83370b31a915 ("selinux: fix error initialization in inode_doinit_with_dentry()"), changed how failures were handled before a SELinux policy was loaded. Unfortunately that patch was potentially problematic for two reasons: it set the isec->initialized state without holding a lock, and it didn't set the inode's SELinux label to the "default" for the particular filesystem. The later can be a problem if/when a later attempt to revalidate the inode fails and SELinux reverts to the existing inode label. This patch should restore the default inode labeling that existed before the original fix, without affecting the LABEL_INVALID marking such that revalidation will still be attempted in the future. Fixes: 83370b31a915 ("selinux: fix error initialization in inode_doinit_with_dentry()") Reported-by: Sven Schnelle Tested-by: Sven Schnelle Reviewed-by: Ondrej Mosnacek Signed-off-by: Paul Moore Signed-off-by: Sasha Levin

selinux: fix error initialization in inode_doinit_with_dentry()

2020-12-30T10:25:50+00:00

[ Upstream commit 83370b31a915493231e5b9addc72e4bef69f8d31 ] Mark the inode security label as invalid if we cannot find a dentry so that we will retry later rather than marking it initialized with the unlabeled SID. Fixes: 9287aed2ad1f ("selinux: Convert isec->lock into a spinlock") Signed-off-by: Tianyue Ren [PM: minor comment tweaks] Signed-off-by: Paul Moore Signed-off-by: Sasha Levin

selinux: Fix error return code in sel_ib_pkey_sid_slow()

2020-11-18T18:18:50+00:00

commit c350f8bea271782e2733419bd2ab9bf4ec2051ef upstream. Fix to return a negative error code from the error handling case instead of 0 in function sel_ib_pkey_sid_slow(), as done elsewhere in this function. Cc: stable@vger.kernel.org Fixes: 409dcf31538a ("selinux: Add a cache for quicker retreival of PKey SIDs") Reported-by: Hulk Robot Signed-off-by: Chen Zhou Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

evm: Check size of security.evm before using it

2020-11-05T10:08:34+00:00

commit 455b6c9112eff8d249e32ba165742085678a80a4 upstream. This patch checks the size for the EVM_IMA_XATTR_DIGSIG and EVM_XATTR_PORTABLE_DIGSIG types to ensure that the algorithm is read from the buffer returned by vfs_getxattr_alloc(). Cc: stable@vger.kernel.org # 4.19.x Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures") Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: Don't ignore errors from crypto_shash_update()

2020-10-29T08:54:59+00:00

commit 60386b854008adc951c470067f90a2d85b5d520f upstream. Errors returned by crypto_shash_update() are not checked in ima_calc_boot_aggregate_tfm() and thus can be overwritten at the next iteration of the loop. This patch adds a check after calling crypto_shash_update() and returns immediately if the result is not zero. Cc: stable@vger.kernel.org Fixes: 3323eec921efd ("integrity: IMA as an integrity service provider") Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

selinux: sel_avc_get_stat_idx should increase position index

2020-10-01T11:14:33+00:00

[ Upstream commit 8d269a8e2a8f0bca89022f4ec98de460acb90365 ] If seq_file .next function does not change position index, read after some lseek can generate unexpected output. $ dd if=/sys/fs/selinux/avc/cache_stats # usual output lookups hits misses allocations reclaims frees 817223 810034 7189 7189 6992 7037 1934894 1926896 7998 7998 7632 7683 1322812 1317176 5636 5636 5456 5507 1560571 1551548 9023 9023 9056 9115 0+1 records in 0+1 records out 189 bytes copied, 5,1564e-05 s, 3,7 MB/s $# read after lseek to midle of last line $ dd if=/sys/fs/selinux/avc/cache_stats bs=180 skip=1 dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset 056 9115 <<<< end of last line 1560571 1551548 9023 9023 9056 9115 <<< whole last line once again 0+1 records in 0+1 records out 45 bytes copied, 8,7221e-05 s, 516 kB/s $# read after lseek beyond end of of file $ dd if=/sys/fs/selinux/avc/cache_stats bs=1000 skip=1 dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset 1560571 1551548 9023 9023 9056 9115 <<<< generates whole last line 0+1 records in 0+1 records out 36 bytes copied, 9,0934e-05 s, 396 kB/s https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Acked-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Sasha Levin

selinux: allow labeling before policy is loaded

2020-10-01T11:14:23+00:00

[ Upstream commit 3e3e24b42043eceb97ed834102c2d094dfd7aaa6 ] Currently, the SELinux LSM prevents one from setting the `security.selinux` xattr on an inode without a policy first being loaded. However, this restriction is problematic: it makes it impossible to have newly created files with the correct label before actually loading the policy. This is relevant in distributions like Fedora, where the policy is loaded by systemd shortly after pivoting out of the initrd. In such instances, all files created prior to pivoting will be unlabeled. One then has to relabel them after pivoting, an operation which inherently races with other processes trying to access those same files. Going further, there are use cases for creating the entire root filesystem on first boot from the initrd (e.g. Container Linux supports this today[1], and we'd like to support it in Fedora CoreOS as well[2]). One can imagine doing this in two ways: at the block device level (e.g. laying down a disk image), or at the filesystem level. In the former, labeling can simply be part of the image. But even in the latter scenario, one still really wants to be able to set the right labels when populating the new filesystem. This patch enables this by changing behaviour in the following two ways: 1. allow `setxattr` if we're not initialized 2. don't try to set the in-core inode SID if we're not initialized; instead leave it as `LABEL_INVALID` so that revalidation may be attempted at a later time Note the first hunk of this patch is mostly the same as a previously discussed one[3], though it was part of a larger series which wasn't accepted. [1] https://coreos.com/os/docs/latest/root-filesystem-placement.html [2] https://github.com/coreos/fedora-coreos-tracker/issues/94 [3] https://www.spinics.net/lists/linux-initramfs/msg04593.html Co-developed-by: Victor Kamensky Signed-off-by: Victor Kamensky Signed-off-by: Jonathan Lebon Signed-off-by: Paul Moore Signed-off-by: Sasha Levin

Smack: prevent underflow in smk_set_cipso()

2020-08-19T06:14:59+00:00

[ Upstream commit 42a2df3e829f3c5562090391b33714b2e2e5ad4a ] We have an upper bound on "maplevel" but forgot to check for negative values. Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel") Signed-off-by: Dan Carpenter Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin

Smack: fix another vsscanf out of bounds

2020-08-19T06:14:59+00:00

[ Upstream commit a6bd4f6d9b07452b0b19842044a6c3ea384b0b88 ] This is similar to commit 84e99e58e8d1 ("Smack: slab-out-of-bounds in vsscanf") where we added a bounds check on "rule". Reported-by: syzbot+a22c6092d003d6fe1122@syzkaller.appspotmail.com Fixes: f7112e6c9abf ("Smack: allow for significantly longer Smack labels v4") Signed-off-by: Dan Carpenter Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin