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* kernel: Fix potential refcount leak in su checkTom Marshall2017-06-071-1/+3
| | | | Change-Id: I8d2c8bed65a01eb0928308df638a04449a5bd881
* kernel: Only expose su when daemon is runningTom Marshall2017-06-073-0/+33
| | | | | | | | | | | | | | | | | It has been claimed that the PG implementation of 'su' has security vulnerabilities even when disabled. Unfortunately, the people that find these vulnerabilities often like to keep them private so they can profit from exploits while leaving users exposed to malicious hackers. In order to reduce the attack surface for vulnerabilites, it is therefore necessary to make 'su' completely inaccessible when it is not in use (except by the root and system users). Change-Id: Ia7d50ba46c3d932c2b0ca5fc8e9ec69ec9045f85 Adapted from https://review.lineageos.org/#/c/170648 Used @stargo's PF_SU/PF_FREEZER_NOSIG overlap fix Signed-off-by: D. Andrei Măceș <dmaces@nd.edu>
* ext4: short-cut orphan cleanup on errorVegard Nossum2017-05-101-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c65d5c6c81a1f27dec5f627f67840726fcd146de upstream. If we encounter a filesystem error during orphan cleanup, we should stop. Otherwise, we may end up in an infinite loop where the same inode is processed again and again. EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended EXT4-fs error (device loop0): ext4_mb_generate_buddy:758: group 2, block bitmap and bg descriptor inconsistent: 6117 vs 0 free clusters Aborting journal on device loop0-8. EXT4-fs (loop0): Remounting filesystem read-only EXT4-fs error (device loop0) in ext4_free_blocks:4895: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs error (device loop0) in ext4_ext_remove_space:3068: IO failure EXT4-fs error (device loop0) in ext4_ext_truncate:4667: Journal has aborted EXT4-fs error (device loop0) in ext4_orphan_del:2927: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs (loop0): Inode 16 (00000000618192a0): orphan list check failed! [...] EXT4-fs (loop0): Inode 16 (0000000061819748): orphan list check failed! [...] EXT4-fs (loop0): Inode 16 (0000000061819bf0): orphan list check failed! [...] Change-Id: I5004d92629fecfbca5e2d8b1225bec2038199a54 See-also: c9eb13a9105 ("ext4: fix hang when processing corrupted orphaned inode list") Cc: Jan Kara <jack@suse.cz> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ext4: fix hang when processing corrupted orphaned inode listTheodore Ts'o2017-05-101-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c9eb13a9105e2e418f72e46a2b6da3f49e696902 upstream. If the orphaned inode list contains inode #5, ext4_iget() returns a bad inode (since the bootloader inode should never be referenced directly). Because of the bad inode, we end up processing the inode repeatedly and this hangs the machine. This can be reproduced via: mke2fs -t ext4 /tmp/foo.img 100 debugfs -w -R "ssv last_orphan 5" /tmp/foo.img mount -o loop /tmp/foo.img /mnt (But don't do this if you are using an unpatched kernel if you care about the system staying functional. :-) This bug was found by the port of American Fuzzy Lop into the kernel to find file system problems[1]. (Since it *only* happens if inode #5 shows up on the orphan list --- 3, 7, 8, etc. won't do it, it's not surprising that AFL needed two hours before it found it.) [1] http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf Reported by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Change-Id: I1653cbd9c355c925d936fec91c85a22e2288116f
* ecryptfs: don't allow mmap when the lower fs doesn't support itJeff Mahoney2017-03-171-0/+8
| | | | | | | | | | | | | | There are legitimate reasons to disallow mmap on certain files, notably in sysfs or procfs. We shouldn't emulate mmap support on file systems that don't offer support natively. CVE-2016-1583 Change-Id: I378990d848df48abfe4b58b08cc64e3563577474 Signed-off-by: Jeff Mahoney <jeffm@suse.com> Cc: stable@vger.kernel.org [tyhicks: clean up f_op check by using ecryptfs_file_to_lower()] Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
* ext4: validate s_first_meta_bg at mount timeEryu Guan2017-03-171-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ralf Spenneberg reported that he hit a kernel crash when mounting a modified ext4 image. And it turns out that kernel crashed when calculating fs overhead (ext4_calculate_overhead()), this is because the image has very large s_first_meta_bg (debug code shows it's 842150400), and ext4 overruns the memory in count_overhead() when setting bitmap buffer, which is PAGE_SIZE. ext4_calculate_overhead(): buf = get_zeroed_page(GFP_NOFS); <=== PAGE_SIZE buffer blks = count_overhead(sb, i, buf); count_overhead(): for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) { <=== j = 842150400 ext4_set_bit(EXT4_B2C(sbi, s++), buf); <=== buffer overrun count++; } This can be reproduced easily for me by this script: #!/bin/bash rm -f fs.img mkdir -p /mnt/ext4 fallocate -l 16M fs.img mke2fs -t ext4 -O bigalloc,meta_bg,^resize_inode -F fs.img debugfs -w -R "ssv first_meta_bg 842150400" fs.img mount -o loop fs.img /mnt/ext4 Fix it by validating s_first_meta_bg first at mount time, and refusing to mount if its value exceeds the largest possible meta_bg number. Change-Id: If8f0dbed1ed36f3ef9b4466feb4245d8ba5c89b6 Reported-by: Ralf Spenneberg <ralf@os-t.de> Signed-off-by: Eryu Guan <guaneryu@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca>
* BACKPORT: aio: mark AIO pseudo-fs noexecNick Desaulniers2017-03-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This ensures that do_mmap() won't implicitly make AIO memory mappings executable if the READ_IMPLIES_EXEC personality flag is set. Such behavior is problematic because the security_mmap_file LSM hook doesn't catch this case, potentially permitting an attacker to bypass a W^X policy enforced by SELinux. I have tested the patch on my machine. To test the behavior, compile and run this: #define _GNU_SOURCE #include <unistd.h> #include <sys/personality.h> #include <linux/aio_abi.h> #include <err.h> #include <stdlib.h> #include <stdio.h> #include <sys/syscall.h> int main(void) { personality(READ_IMPLIES_EXEC); aio_context_t ctx = 0; if (syscall(__NR_io_setup, 1, &ctx)) err(1, "io_setup"); char cmd[1000]; sprintf(cmd, "cat /proc/%d/maps | grep -F '/[aio]'", (int)getpid()); system(cmd); return 0; } In the output, "rw-s" is good, "rwxs" is bad. Signed-off-by: Jann Horn <jann@thejh.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit 22f6b4d34fcf039c63a94e7670e0da24f8575a5a) Bug: 31711619 Change-Id: I9f2872703bef240d6b82320c744529459bb076dc
* isofs: Fix infinite looping over CE entriesJan Kara2017-03-171-0/+6
| | | | | | | | | | | | | | | | Rock Ridge extensions define so called Continuation Entries (CE) which define where is further space with Rock Ridge data. Corrupted isofs image can contain arbitrarily long chain of these, including a one containing loop and thus causing kernel to end in an infinite loop when traversing these entries. Limit the traversal to 32 entries which should be more than enough space to store all the Rock Ridge data. Change-Id: I2c81b49e68144483186ea5fc35d052529ac001cb Reported-by: P J P <ppandit@redhat.com> CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz>
* block: fix use-after-free in sys_ioprio_get()Omar Sandoval2016-11-091-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | get_task_ioprio() accesses the task->io_context without holding the task lock and thus can race with exit_io_context(), leading to a use-after-free. The reproducer below hits this within a few seconds on my 4-core QEMU VM: int main(int argc, char **argv) { pid_t pid, child; long nproc, i; /* ioprio_set(IOPRIO_WHO_PROCESS, 0, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0)); */ syscall(SYS_ioprio_set, 1, 0, 0x6000); nproc = sysconf(_SC_NPROCESSORS_ONLN); for (i = 0; i < nproc; i++) { pid = fork(); assert(pid != -1); if (pid == 0) { for (;;) { pid = fork(); assert(pid != -1); if (pid == 0) { _exit(0); } else { child = wait(NULL); assert(child == pid); } } } pid = fork(); assert(pid != -1); if (pid == 0) { for (;;) { /* ioprio_get(IOPRIO_WHO_PGRP, 0); */ syscall(SYS_ioprio_get, 2, 0); } } } for (;;) { /* ioprio_get(IOPRIO_WHO_PGRP, 0); */ syscall(SYS_ioprio_get, 2, 0); } return 0; } This gets us KASAN dumps like this: [ 35.526914] ================================================================== [ 35.530009] BUG: KASAN: out-of-bounds in get_task_ioprio+0x7b/0x90 at addr ffff880066f34e6c [ 35.530009] Read of size 2 by task ioprio-gpf/363 [ 35.530009] ============================================================================= [ 35.530009] BUG blkdev_ioc (Not tainted): kasan: bad access detected [ 35.530009] ----------------------------------------------------------------------------- [ 35.530009] Disabling lock debugging due to kernel taint [ 35.530009] INFO: Allocated in create_task_io_context+0x2b/0x370 age=0 cpu=0 pid=360 [ 35.530009] ___slab_alloc+0x55d/0x5a0 [ 35.530009] __slab_alloc.isra.20+0x2b/0x40 [ 35.530009] kmem_cache_alloc_node+0x84/0x200 [ 35.530009] create_task_io_context+0x2b/0x370 [ 35.530009] get_task_io_context+0x92/0xb0 [ 35.530009] copy_process.part.8+0x5029/0x5660 [ 35.530009] _do_fork+0x155/0x7e0 [ 35.530009] SyS_clone+0x19/0x20 [ 35.530009] do_syscall_64+0x195/0x3a0 [ 35.530009] return_from_SYSCALL_64+0x0/0x6a [ 35.530009] INFO: Freed in put_io_context+0xe7/0x120 age=0 cpu=0 pid=1060 [ 35.530009] __slab_free+0x27b/0x3d0 [ 35.530009] kmem_cache_free+0x1fb/0x220 [ 35.530009] put_io_context+0xe7/0x120 [ 35.530009] put_io_context_active+0x238/0x380 [ 35.530009] exit_io_context+0x66/0x80 [ 35.530009] do_exit+0x158e/0x2b90 [ 35.530009] do_group_exit+0xe5/0x2b0 [ 35.530009] SyS_exit_group+0x1d/0x20 [ 35.530009] entry_SYSCALL_64_fastpath+0x1a/0xa4 [ 35.530009] INFO: Slab 0xffffea00019bcd00 objects=20 used=4 fp=0xffff880066f34ff0 flags=0x1fffe0000004080 [ 35.530009] INFO: Object 0xffff880066f34e58 @offset=3672 fp=0x0000000000000001 [ 35.530009] ================================================================== Fix it by grabbing the task lock while we poke at the io_context. Change-Id: I4261aaf076fab943a80a45b0a77e023aa4ecbbd8 Cc: stable@vger.kernel.org Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* mnt: Prevent pivot_root from creating a loop in the mount treeEric W. Biederman2016-10-271-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andy Lutomirski recently demonstrated that when chroot is used to set the root path below the path for the new ``root'' passed to pivot_root the pivot_root system call succeeds and leaks mounts. In examining the code I see that starting with a new root that is below the current root in the mount tree will result in a loop in the mount tree after the mounts are detached and then reattached to one another. Resulting in all kinds of ugliness including a leak of that mounts involved in the leak of the mount loop. Prevent this problem by ensuring that the new mount is reachable from the current root of the mount tree. [Added stable cc. Fixes CVE-2014-7970. --Andy] Cc: stable@vger.kernel.org Reported-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/87bnpmihks.fsf@x220.int.ebiederm.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> (backported from commit 0d0826019e529f21c84687521d03f60cd241ca7d) CVE-2014-7970 BugLink: http://bugs.launchpad.net/bugs/1383356 Signed-off-by: Luis Henriques <luis.henriques@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> Acked-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Change-Id: I0fe1d090eeb4765cc49401784e44a430f9585498
* vfs: more mnt_parent cleanupsAl Viro2016-10-274-55/+29
| | | | | | | | | | | | | | | | | | | | | a) mount --move is checking that ->mnt_parent is non-NULL before looking if that parent happens to be shared; ->mnt_parent is never NULL and it's not even an misspelled !mnt_has_parent() b) pivot_root open-codes is_path_reachable(), poorly. c) so does path_is_under(), while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> (backported from commit afac7cba7ed31968a95e181dc25e204e45009ea8) CVE-2014-7970 BugLink: http://bugs.launchpad.net/bugs/1383356 Signed-off-by: Luis Henriques <luis.henriques@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> Acked-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Change-Id: I6b2297f46388f135c1b760a37d45efc0e33542db
* vfs: new internal helper: mnt_has_parent(mnt)Al Viro2016-10-275-12/+18
| | | | | | | | | | | | | | | | | | | | | vfsmounts have ->mnt_parent pointing either to a different vfsmount or to itself; it's never NULL and termination condition in loops traversing the tree towards root is mnt == mnt->mnt_parent. At least one place (see the next patch) is confused about what's going on; let's add an explicit helper checking it right way and use it in all places where we need it. Not that there had been too many, but... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> (cherry picked from commit b2dba1af3c4157040303a76d25216b1713d333d0) CVE-2014-7970 BugLink: http://bugs.launchpad.net/bugs/1383356 Signed-off-by: Luis Henriques <luis.henriques@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> Acked-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Change-Id: Iaa5ab510804f3b17fe71197b8919d663a416bf05
* mnt: Only change user settable mount flags in remountEric W. Biederman2016-10-271-1/+1
| | | | | | | | | | | | | | | | | | | | | commit a6138db815df5ee542d848318e5dae681590fccd upstream. Kenton Varda <kenton@sandstorm.io> discovered that by remounting a read-only bind mount read-only in a user namespace the MNT_LOCK_READONLY bit would be cleared, allowing an unprivileged user to the remount a read-only mount read-write. Correct this by replacing the mask of mount flags to preserve with a mask of mount flags that may be changed, and preserve all others. This ensures that any future bugs with this mask and remount will fail in an easy to detect way where new mount flags simply won't change. Change-Id: I8ab8bda03a14b9b43e78f1dc6c818bbec048e986 Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Francis Moreau <francis.moro@gmail.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
* vfs: make AIO use the proper rw_verify_area() area helpersLinus Torvalds2016-10-271-0/+4
| | | | | | | | | | | | | | | | | | | | | commit a70b52ec1aaeaf60f4739edb1b422827cb6f3893 upstream. We had for some reason overlooked the AIO interface, and it didn't use the proper rw_verify_area() helper function that checks (for example) mandatory locking on the file, and that the size of the access doesn't cause us to overflow the provided offset limits etc. Instead, AIO did just the security_file_permission() thing (that rw_verify_area() also does) directly. This fixes it to do all the proper helper functions, which not only means that now mandatory file locking works with AIO too, we can actually remove lines of code. Change-Id: I162d100243d015d50874a826ee3d718d5d3619fa Reported-by: Manish Honap <manish_honap_vit@yahoo.co.in> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs: ext4: disable support for fallocate FALLOC_FL_PUNCH_HOLENick Desaulniers2016-10-131-0/+7
| | | | | | Bug: 28760453 Change-Id: I019c2de559db9e4b95860ab852211b456d78c4ca Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
* mnt: Fail collect_mounts when applied to unmounted mountsEric W. Biederman2016-10-121-1/+5
| | | | | | | | | | | | | | | | | | | | | | | The only users of collect_mounts are in audit_tree.c In audit_trim_trees and audit_add_tree_rule the path passed into collect_mounts is generated from kern_path passed an audit_tree pathname which is guaranteed to be an absolute path. In those cases collect_mounts is obviously intended to work on mounted paths and if a race results in paths that are unmounted when collect_mounts it is reasonable to fail early. The paths passed into audit_tag_tree don't have the absolute path check. But are used to play with fsnotify and otherwise interact with the audit_trees, so again operating only on mounted paths appears reasonable. Avoid having to worry about what happens when we try and audit unmounted filesystems by restricting collect_mounts to mounts that appear in the mount tree. Change-Id: I2edfee6d6951a2179ce8f53785b65ddb1eb95629 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* pipe: limit the per-user amount of pages allocated in pipesWilly Tarreau2016-10-121-2/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On no-so-small systems, it is possible for a single process to cause an OOM condition by filling large pipes with data that are never read. A typical process filling 4000 pipes with 1 MB of data will use 4 GB of memory. On small systems it may be tricky to set the pipe max size to prevent this from happening. This patch makes it possible to enforce a per-user soft limit above which new pipes will be limited to a single page, effectively limiting them to 4 kB each, as well as a hard limit above which no new pipes may be created for this user. This has the effect of protecting the system against memory abuse without hurting other users, and still allowing pipes to work correctly though with less data at once. The limit are controlled by two new sysctls : pipe-user-pages-soft, and pipe-user-pages-hard. Both may be disabled by setting them to zero. The default soft limit allows the default number of FDs per process (1024) to create pipes of the default size (64kB), thus reaching a limit of 64MB before starting to create only smaller pipes. With 256 processes limited to 1024 FDs each, this results in 1024*64kB + (256*1024 - 1024) * 4kB = 1084 MB of memory allocated for a user. The hard limit is disabled by default to avoid breaking existing applications that make intensive use of pipes (eg: for splicing). Reported-by: socketpair@gmail.com Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Mitigates: CVE-2013-4312 (Linux 2.0+) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: Documentation/sysctl/fs.txt fs/pipe.c include/linux/sched.h Change-Id: Ic7c678af18129943e16715fdaa64a97a7f0854be
* pipe: Fix buffer offset after partially failed readBen Hutchings2016-10-121-1/+4
| | | | | | | | | | | | | | | | | | | | Quoting the RHEL advisory: > It was found that the fix for CVE-2015-1805 incorrectly kept buffer > offset and buffer length in sync on a failed atomic read, potentially > resulting in a pipe buffer state corruption. A local, unprivileged user > could use this flaw to crash the system or leak kernel memory to user > space. (CVE-2016-0774, Moderate) The same flawed fix was applied to stable branches from 2.6.32.y to 3.14.y inclusive, and I was able to reproduce the issue on 3.2.y. We need to give pipe_iov_copy_to_user() a separate offset variable and only update the buffer offset if it succeeds. Change-Id: I988802f38acf40c7671fa0978880928b02d29b56 References: https://rhn.redhat.com/errata/RHSA-2016-0103.html Signed-off-by: Ben Hutchings <ben@decadent.org.uk> (cherry picked from commit feae3ca2e5e1a8f44aa6290255d3d9709985d0b2)
* pipe: iovec: Fix memory corruption when retrying atomic copy as non-atomicBen Hutchings2016-10-121-23/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | pipe_iov_copy_{from,to}_user() may be tried twice with the same iovec, the first time atomically and the second time not. The second attempt needs to continue from the iovec position, pipe buffer offset and remaining length where the first attempt failed, but currently the pipe buffer offset and remaining length are reset. This will corrupt the piped data (possibly also leading to an information leak between processes) and may also corrupt kernel memory. This was fixed upstream by commits f0d1bec9d58d ("new helper: copy_page_from_iter()") and 637b58c2887e ("switch pipe_read() to copy_page_to_iter()"), but those aren't suitable for stable. This fix for older kernel versions was made by Seth Jennings for RHEL and I have extracted it from their update. CVE-2015-1805 Bug: 27275324 Change-Id: I459adb9076fcd50ff1f1c557089c4e421b036ec4 References: https://bugzilla.redhat.com/show_bug.cgi?id=1202855 Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (cherry picked from commit 85c34d007116f8a8aafb173966a605fb03532f45)
* fuse: break infinite loop in fuse_fill_write_pages()Roman Gushchin2016-10-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I got a report about unkillable task eating CPU. Further investigation shows, that the problem is in the fuse_fill_write_pages() function. If iov's first segment has zero length, we get an infinite loop, because we never reach iov_iter_advance() call. Fix this by calling iov_iter_advance() before repeating an attempt to copy data from userspace. A similar problem is described in 124d3b7041f ("fix writev regression: pan hanging unkillable and un-straceable"). If zero-length segmend is followed by segment with invalid address, iov_iter_fault_in_readable() checks only first segment (zero-length), iov_iter_copy_from_user_atomic() skips it, fails at second and returns zero -> goto again without skipping zero-length segment. Patch calls iov_iter_advance() before goto again: we'll skip zero-length segment at second iteraction and iov_iter_fault_in_readable() will detect invalid address. Special thanks to Konstantin Khlebnikov, who helped a lot with the commit description. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Maxim Patlasov <mpatlasov@parallels.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Fixes: ea9b9907b82a ("fuse: implement perform_write") Cc: <stable@vger.kernel.org> Conflicts: fs/fuse/file.c Change-Id: Id37193373294dd43191469389cfe68ca1736a54b
* ext4: make orphan functions be no-op in no-journal modeAnatol Pomozov2016-10-121-4/+3
| | | | | | | | | | | | | | | Instead of checking whether the handle is valid, we check if journal is enabled. This avoids taking the s_orphan_lock mutex in all cases when there is no journal in use, including the error paths where ext4_orphan_del() is called with a handle set to NULL. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Conflicts: fs/ext4/namei.c Change-Id: I734ccb8069fceb12b864e7b9dceb37e27ab94c61
* pagemap: do not leak physical addresses to non-privileged userspaceKirill A. Shutemov2016-10-121-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit ab676b7d6fbf4b294bf198fb27ade5b0e865c7ce upstream. As pointed by recent post[1] on exploiting DRAM physical imperfection, /proc/PID/pagemap exposes sensitive information which can be used to do attacks. This disallows anybody without CAP_SYS_ADMIN to read the pagemap. [1] http://googleprojectzero.blogspot.com/2015/03/exploiting-dram-rowhammer-bug-to-gain.html [ Eventually we might want to do anything more finegrained, but for now this is the simple model. - Linus ] Change-Id: Ib62bf4429dcdafd9fc1cd9b1a0c5665c64cc5d18 Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Seaborn <mseaborn@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Zefan Li <lizefan@huawei.com> [mancha: Backported to 3.10] Signed-off-by: mancha security <mancha1@zoho.com>
* fs: take i_mutex during prepare_binprm for set[ug]id executablesJann Horn2016-10-121-25/+40
| | | | | | | | | | | | | | | | This prevents a race between chown() and execve(), where chowning a setuid-user binary to root would momentarily make the binary setuid root. This patch was mostly written by Linus Torvalds. Signed-off-by: Jann Horn <jann@thejh.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Conflicts: fs/exec.c Change-Id: Iecebf23d07e299689e4ba4fd74ea8821ef96e72b
* vfs: read file_handle only once in handle_to_pathSasha Levin2016-10-121-2/+3
| | | | | | | | | | | | | | | We used to read file_handle twice. Once to get the amount of extra bytes, and once to fetch the entire structure. This may be problematic since we do size verifications only after the first read, so if the number of extra bytes changes in userspace between the first and second calls, we'll have an incoherent view of file_handle. Instead, read the constant size once, and copy that over to the final structure without having to re-read it again. Change-Id: I7480e096308e66d24622416cbb50407669ab351d Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
* eCryptfs: Remove buggy and unnecessary write in file name decode routineMichael Halcrow2016-10-121-1/+0
| | | | | | | | | | | | | | Dmitry Chernenkov used KASAN to discover that eCryptfs writes past the end of the allocated buffer during encrypted filename decoding. This fix corrects the issue by getting rid of the unnecessary 0 write when the current bit offset is 2. Change-Id: Id8e04a580e550495c46cd36fec430a1ec4342940 Signed-off-by: Michael Halcrow <mhalcrow@google.com> Reported-by: Dmitry Chernenkov <dmitryc@google.com> Suggested-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org # v2.6.29+: 51ca58d eCryptfs: Filename Encryption: Encoding and encryption functions Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
* f2fs: fix to cover io->bio with io_rwsemJaegeuk Kim2016-06-051-3/+2
| | | | | | | In the f2fs_wait_on_page_writeback, io->bio should be covered by io_rwsem. Otherwise, the bio pointer can become a dangling pointer due to data races. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: fix error path when fail to read inline dataChao Yu2016-06-052-5/+13
| | | | | | | | | We should unlock page in ->readpage() path and also should unlock & release page in error path of ->write_begin() to avoid deadlock or memory leak. So let's add release code to fix the problem when we fail to read inline data. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: use list_for_each_entry{_safe} for simplyfying codeChao Yu2016-06-054-41/+24
| | | | | | | | This patch use list_for_each_entry{_safe} instead of list_for_each{_safe} for simplfying code. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid free slab cache under spinlockChao Yu2016-06-052-11/+33
| | | | | | | | | | | Move kmem_cache_free out of spinlock protection region for better performance. Change log from v1: o remove spinlock protection for kmem_cache_free in destroy_node_manager suggested by Jaegeuk Kim. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid unneeded lookup when xattr name length is too longChao Yu2016-06-051-0/+2
| | | | | | | | In f2fs_setxattr we have limit this attribute name length, so we should also check it in f2fs_getxattr to avoid useless lookup caused by invalid name length. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid unnecessary bio submit when wait page writebackChao Yu2016-06-054-8/+34
| | | | | | | | | This patch introduce is_merged_page() to check whether current page is merged in f2fs bio cache. When page is not in cache, we can avoid submitting bio cache, resulting in having more chance to merge pages. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: return -EIO when node id is not matchedJaegeuk Kim2016-06-051-2/+1
| | | | | | | | During the cleaing of node segments, F2FS can get errored node blocks due to data race between node page lock and its valid bitmap operations. In that case, it needs to return an error to skip such the obsolete block copy. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid RECLAIM_FS-ON-W warningJaegeuk Kim2016-06-052-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch should resolve the following possible bug. RECLAIM_FS-ON-W at: mark_held_locks+0xb9/0x140 lockdep_trace_alloc+0x85/0xf0 __kmalloc+0x53/0x1d0 read_all_xattrs+0x3d1/0x3f0 [f2fs] f2fs_getxattr+0x4f/0x100 [f2fs] f2fs_get_acl+0x4c/0x290 [f2fs] get_acl+0x4f/0x80 posix_acl_create+0x72/0x180 f2fs_init_acl+0x29/0xcc [f2fs] __f2fs_add_link+0x259/0x710 [f2fs] f2fs_create+0xad/0x1c0 [f2fs] vfs_create+0xed/0x150 do_last+0xd36/0xed0 path_openat+0xc5/0x680 do_filp_open+0x43/0xa0 do_sys_open+0x13c/0x230 SyS_creat+0x1e/0x20 system_call_fastpath+0x16/0x1b Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: skip unnecessary node writes during fsyncJaegeuk Kim2016-06-054-9/+32
| | | | | | | | | | | | | If multiple redundant fsync calls are triggered, we don't need to write its node pages with fsync mark continuously. So, this patch adds FI_NEED_FSYNC to track whether the latest node block is written with the fsync mark or not. If the mark was set, a new fsync doesn't need to write a node block. Otherwise, we should do a new node block with the mark for roll-forward recovery. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: introduce fi->i_sem to protect fi's infoJaegeuk Kim2016-06-056-4/+28
| | | | | | | | | | This patch introduces fi->i_sem to protect fi's info that includes xattr_ver, pino, i_nlink. This enables to remove i_mutex during f2fs_sync_file, resulting in performance improvement when a number of fsync calls are triggered from many concurrent threads. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: change reclaim rate in percentageJaegeuk Kim2016-06-052-2/+3
| | | | | | | | | It is more reasonable to determine the reclaiming rate of prefree segments according to the volume size, which is set to 5% by default. For example, if the volume is 128GB, the prefree segments are reclaimed when the number reaches to 6.4GB. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: remove unnecessary thresholdJaegeuk Kim2016-06-053-11/+5
| | | | | | | The NM_WOUT_THRESHOLD is now obsolete since f2fs starts to control on a basis of the memory footprint. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: throttle the memory footprint with a sysfs entryJaegeuk Kim2016-06-054-6/+34
| | | | | | | | | | | | | | | | | This patch introduces ram_thresh, a sysfs entry, which controls the memory footprint used by the free nid list and the nat cache. Previously, the free nid list was controlled by MAX_FREE_NIDS, while the nat cache was managed by NM_WOUT_THRESHOLD. However, this approach cannot be applied dynamically according to the system. So, this patch adds ram_thresh that users can specify the threshold, which is in order of 1 / 1024. For example, if the total ram size is 4GB and the value is set to 10 by default, f2fs tries to control the number of free nids and nat caches not to consume over 10 * (4GB / 1024) = 10MB. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid to drop nat entries due to the negative nr_shrinkJaegeuk Kim2016-06-051-1/+1
| | | | | | | The try_to_free_nats should not receive the negative nr_shrink. Otherwise, it can drop all the nat entries by the while loop. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: call f2fs_wait_on_page_writeback instead of native functionJaegeuk Kim2016-06-055-19/+16
| | | | | | | | If a page is on writeback, f2fs can face with deadlock due to under writepages. This is caused by merging IOs inside f2fs, so if it comes to detect, let's throw merged IOs, which is implemented by f2fs_wait_on_page_writeback. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: introduce nr_pages_to_write for segment alignmentJaegeuk Kim2016-06-054-19/+36
| | | | | | | | This patch introduces nr_pages_to_write to align page writes to the segment or other operational unit size, which can be tuned according to the system environment. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: increase pages_skipped when skipping writepagesJaegeuk Kim2016-06-053-7/+16
| | | | | | This patch increases pages_skipped when skipping writepages. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid small data writes by skipping writepagesJaegeuk Kim2016-06-054-9/+26
| | | | | | | | | This patch introduces nr_pages_to_skip(sbi, type) to determine writepages can be skipped. The dentry, node, and meta pages can be conrolled by F2FS without breaking the FS consistency. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: introduce get_dirty_dents for readabilityJaegeuk Kim2016-06-053-2/+7
| | | | | | The get_dirty_dents gives us the number of dirty dentry pages. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: fix incorrect parsing with option stringChao Yu2016-06-051-2/+2
| | | | | | | | | | | Previously 'background_gc={on***,off***}' is being parsed as correct option, with this patch we cloud fix the trivial bug in mount process. Change log from v1: o need to check length of parameter suggested by Jaegeuk Kim. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: avoid to return incorrect errno of read_normal_summariesChao Yu2016-06-051-3/+7
| | | | | | | | We should return error number of read_normal_summaries instead of -EINVAL when read_normal_summaries failed. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: introduce f2fs_has_xattr_block for better readabilityChao Yu2016-06-053-3/+8
| | | | | | | | This patch introduces a help function f2fs_has_xattr_block for better readability. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: print type for each segment in segment_info's showChao Yu2016-06-051-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original segment_info's show looks out-of-format: cat /proc/fs/f2fs/loop0/segment_info 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 512 512 512 512 512 512 512 512 0 0 512 348 0 263 0 0 512 0 0 512 512 512 512 0 512 512 512 512 512 512 512 512 512 511 328 512 512 512 512 512 512 512 512 512 512 512 512 512 0 0 175 Let's fix this and show type for each segment. cat /proc/fs/f2fs/loop0/segment_info format: segment_type|valid_blocks segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN) 0 2|0 1|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 10 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 20 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 30 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 40 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 0|0 50 3|0 3|0 3|0 3|0 3|0 3|0 3|0 0|0 3|0 3|0 60 3|0 3|0 3|0 3|0 3|0 3|0 3|0 3|0 3|0 3|512 70 3|512 3|512 3|512 3|512 3|512 3|512 3|512 3|0 3|0 3|512 80 3|0 3|0 3|0 3|0 3|0 3|512 3|0 3|0 3|512 3|512 90 3|512 0|512 3|274 0|512 0|512 0|512 0|512 0|512 0|512 3|512 100 3|512 0|512 3|511 0|328 3|512 0|512 0|512 3|512 0|512 0|512 110 0|512 0|512 0|512 0|512 0|512 0|512 0|512 5|0 4|0 3|512 Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: check upper bound of ino value in f2fs_nfs_get_inodeChao Yu2016-06-051-0/+2
| | | | | | | | Upper bound checking of ino should be added to f2fs_nfs_get_inode, so unneeded process before do_read_inode in f2fs_iget could be avoided when ino is invalid. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
* f2fs: introduce f2fs_has_inline_xattr for better readabilityChao Yu2016-06-052-3/+8
| | | | | | | | This patch introduces a help function f2fs_has_inline_xattr for better readability. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
generated by cgit v1.1 at 2024-12-22 17:42:17 +0000