- 28 Jun, 2018 3 commits
-
-
Filipe Manana authored
If a power failure happens while the qgroup rescan kthread is running, the next mount operation will always fail. This is because of a recent regression that makes qgroup_rescan_init() incorrectly return -EINVAL when we are mounting the filesystem (through btrfs_read_qgroup_config()). This causes the -EINVAL error to be returned regardless of any qgroup flags being set instead of returning the error only when neither of the flags BTRFS_QGROUP_STATUS_FLAG_RESCAN nor BTRFS_QGROUP_STATUS_FLAG_ON are set. A test case for fstests follows up soon. Fixes: 9593bf49 ("btrfs: qgroup: show more meaningful qgroup_rescan_init error message") Signed-off-by:
Filipe Manana <fdmanana@suse.com> Reviewed-by:
Qu Wenruo <wqu@suse.com> Signed-off-by:
David Sterba <dsterba@suse.com>
-
Chris Mason authored
The vm_fault_t conversion commit introduced a ret2 variable for tracking the integer return values from internal btrfs functions. It was sometimes returning VM_FAULT_LOCKED for pages that were actually invalid and had been removed from the radix. Something like this: ret2 = btrfs_delalloc_reserve_space() // returns zero on success lock_page(page) if (page->mapping != inode->i_mapping) goto out_unlock; ... out_unlock: if (!ret2) { ... return VM_FAULT_LOCKED; } This ends up triggering this WARNING in btrfs_destroy_inode() WARN_ON(BTRFS_I(inode)->block_rsv.size); xfstests generic/095 was able to reliably reproduce the errors. Since out_unlock: is only used for errors, this fix moves it below the if (!ret2) check we use to return VM_FAULT_LOCKED for success. Fixes: a528a241 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t) Signed-off-by:Chris Mason <clm@fb.com> Reviewed-by:
-
Qu Wenruo authored
Commit ff3d27a0 ("btrfs: qgroup: Finish rescan when hit the last leaf of extent tree") added a new exit for rescan finish. However after finishing quota rescan, we set fs_info->qgroup_rescan_progress to (u64)-1 before we exit through the original exit path. While we missed that assignment of (u64)-1 in the new exit path. The end result is, the quota status item doesn't have the same value. (-1 vs the last bytenr + 1) Although it doesn't affect quota accounting, it's still better to keep the original behavior. Reported-by:
Misono Tomohiro <misono.tomohiro@jp.fujitsu.com> Fixes: ff3d27a0 ("btrfs: qgroup: Finish rescan when hit the last leaf of extent tree") Signed-off-by:
-
- 22 Jun, 2018 1 commit
-
-
Filipe Manana authored
If we failed during a rename exchange operation after starting/joining a transaction, we would end up replacing the return value, stored in the local 'ret' variable, with the return value from btrfs_end_transaction(). So this could end up returning 0 (success) to user space despite the operation having failed and aborted the transaction, because if there are multiple tasks having a reference on the transaction at the time btrfs_end_transaction() is called by the rename exchange, that function returns 0 (otherwise it returns -EIO and not the original error value). So fix this by not overwriting the return value on error after getting a transaction handle. Fixes: cdd1fedf ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT") CC: stable@vger.kernel.org # 4.9+ Signed-off-by:
-
- 21 Jun, 2018 2 commits
-
-
Lu Fengqi authored
If this condition ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) is hit, we will go to free the uninitialized cmp.src_pages and cmp.dst_pages. Fixes: 67b07bd4 ("Btrfs: reuse cmp workspace in EXTENT_SAME ioctl") Signed-off-by:
Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by:
-
Filipe Manana authored
Commit 9d311e11 ("Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero") introduced a regression where we no longer report 0 as the physical offset for inline extents (and other extents with a special block_start value). This is because it always sets the variable used to report the physical offset ("disko") as em->block_start plus some offset, and em->block_start has the value 18446744073709551614 ((u64) -2) for inline extents. This made the btrfs test 004 (from fstests) often fail, for example, for a file with an inline extent we have the following items in the subvolume tree: item 101 key (418 INODE_ITEM 0) itemoff 11029 itemsize 160 generation 25 transid 38 size 1525 nbytes 1525 block group 0 mode 100666 links 1 uid 0 gid 0 rdev 0 sequence 0 flags 0x2(none) atime 1529342058.461891730 (2018-06-18 18:14:18) ctime 1529342058.461891730 (2018-06-18 18:14:18) mtime 1529342058.461891730 (2018-06-18 18:14:18) otime 1529342055.869892885 (2018-06-18 18:14:15) item 102 key (418 INODE_REF 264) itemoff 11016 itemsize 13 index 25 namelen 3 name: fc7 item 103 key (418 EXTENT_DATA 0) itemoff 9470 itemsize 1546 generation 38 type 0 (inline) inline extent data size 1525 ram_bytes 1525 compression 0 (none) Then when test 004 invoked fiemap against the file it got a non-zero physical offset: $ filefrag -v /mnt/p0/d4/d7/fc7 Filesystem type is: 9123683e File size of /mnt/p0/d4/d7/fc7 is 1525 (1 block of 4096 bytes) ext: logical_offset: physical_offset: length: expected: flags: 0: 0.. 4095: 18446744073709551614.. 4093: 4096: last,not_aligned,inline,eof /mnt/p0/d4/d7/fc7: 1 extent found This resulted in the test failing like this: btrfs/004 49s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad) --- tests/btrfs/004.out 2016-08-23 10:17:35.027012095 +0100 +++ /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad 2018-06-18 18:15:02.385872155 +0100 @@ -1,3 +1,10 @@ QA output created by 004 *** test backref walking -*** done +./tests/btrfs/004: line 227: [: 7.55578637259143e+22: integer expression expected +ERROR: 7.55578637259143e+22 is not a valid numeric value. +unexpected output from + /home/fdmanana/git/hub/btrfs-progs/btrfs inspect-internal logical-resolve -s 65536 -P 7.55578637259143e+22 /home/fdmanana/btrfs-tests/scratch_1 ... (Run 'diff -u tests/btrfs/004.out /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad' to see the entire diff) Ran: btrfs/004 The large number in scientific notation reported as an invalid numeric value is the result from the filter passed to perl which multiplies the physical offset by the block size reported by fiemap. So fix this by ensuring the physical offset is always set to 0 when we are processing an extent with a special block_start value. Fixes: 9d311e11 ("Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero") Signed-off-by:
-
- 11 Jun, 2018 1 commit
-
-
Qu Wenruo authored
[BUG] Btrfs can create compressed extent without checksum (even though it shouldn't), and if we then try to replace device containing such extent, the result device will contain all the uncompressed data instead of the compressed one. Test case already submitted to fstests: https://patchwork.kernel.org/patch/10442353/ [CAUSE] When handling compressed extent without checksum, device replace will goe into copy_nocow_pages() function. In that function, btrfs will get all inodes referring to this data extents and then use find_or_create_page() to get pages direct from that inode. The problem here is, pages directly from inode are always uncompressed. And for compressed data extent, they mismatch with on-disk data. Thus this leads to corrupted compressed data extent written to replace device. [FIX] In this attempt, we could just remove the "optimization" branch, and let unified scrub_pages() to handle it. Although scrub_pages() won't bother reusing page cache, it will be a little slower, but it does the correct csum checking and won't cause such data corruption caused by "optimization". Note about the fix: this is the minimal fix that can be backported to older stable trees without conflicts. The whole callchain from copy_nocow_pages() can be deleted, and will be in followup patches. Fixes: ff023aac ("Btrfs: add code to scrub to copy read data to another disk") CC: stable@vger.kernel.org # 4.4+ Reported-by:
James Harvey <jamespharvey20@gmail.com> Reviewed-by:
-
- 07 Jun, 2018 2 commits
-
-
Souptick Joarder authored
Use the new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference commit 1c8f4220 ("mm: change return type to vm_fault_t") vmf_error() is the newly introduced inline function in 4.17-rc6. Signed-off-by:
Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by:
-
Robbie Ko authored
[BUG] fm_mapped_extents is not correct when fm_extent_count is 0 Like: # mount /dev/vdb5 /mnt/btrfs # dd if=/dev/zero bs=16K count=4 oflag=dsync of=/mnt/btrfs/file # xfs_io -c "fiemap -v" /mnt/btrfs/file /mnt/btrfs/file: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..127]: 25088..25215 128 0x1 When user space wants to get the number of file extents, set fm_extent_count to 0 to run fiemap and then read fm_mapped_extents. In the above example, fiemap will return with fm_mapped_extents set to 4, but it should be 1 since there's only one entry in the output. [REASON] The problem seems to be that disko is only set if fieinfo->fi_extents_max is set. And this member is initialized, in the generic ioctl_fiemap function, to the value of used-passed fm_extent_count. So when the user passes 0 then fi_extent_max is also set to zero and this causes btrfs to not initialize disko at all. Eventually this leads emit_fiemap_extent being called with a bogus 'phys' argument preventing proper fiemap entries merging. [FIX] Move the disko initialization earlier in extent_fiemap making it independent of user-passed arguments, allowing emit_fiemap_extent to properly handle consecutive extent entries. Signed-off-by:Robbie Ko <robbieko@synology.com> Signed-off-by:
-
- 05 Jun, 2018 1 commit
-
-
Misono Tomohiro authored
The patch introducing the ioctl was not the latest version at the time of merging to the mainline and needs a fixup from this patch. Fixes: ba637a252d30 ("btrfs: Check error of btrfs_iget() in btrfs_search_path_in_tree_user") Signed-off-by:
-
- 31 May, 2018 3 commits
-
-
Tomohiro Misono authored
Add unprivileged version of ino_lookup ioctl BTRFS_IOC_INO_LOOKUP_USER to allow normal users to call "btrfs subvolume list/show" etc. in combination with BTRFS_IOC_GET_SUBVOL_INFO/BTRFS_IOC_GET_SUBVOL_ROOTREF. This can be used like BTRFS_IOC_INO_LOOKUP but the argument is different. This is because it always searches the fs/file tree correspoinding to the fd with which this ioctl is called and also returns the name of bottom subvolume. The main differences from original ino_lookup ioctl are: 1. Read + Exec permission will be checked using inode_permission() during path construction. -EACCES will be returned in case of failure. 2. Path construction will be stopped at the inode number which corresponds to the fd with which this ioctl is called. If constructed path does not exist under fd's inode, -EACCES will be returned. 3. The name of bottom subvolume is also searched and filled. Note that the maximum length of path is shorter 256 (BTRFS_VOL_NAME_MAX+1) bytes than ino_lookup ioctl because of space of subvolume's name. Reviewed-by:Gu Jinxiang <gujx@cn.fujitsu.com> Reviewed-by:
-
Tomohiro Misono authored
Add unprivileged ioctl BTRFS_IOC_GET_SUBVOL_ROOTREF which returns ROOT_REF information of the subvolume containing this inode except the subvolume name (this is because to prevent potential name leak). The subvolume name will be gained by user version of ino_lookup ioctl (BTRFS_IOC_INO_LOOKUP_USER) which also performs permission check. The min id of root ref's subvolume to be searched is specified by @min_id in struct btrfs_ioctl_get_subvol_rootref_args. After the search ends, @min_id is set to the last searched root ref's subvolid + 1. Also, if there are more root refs than BTRFS_MAX_ROOTREF_BUFFER_NUM, -EOVERFLOW is returned. Therefore the caller can just call this ioctl again without changing the argument to continue search. Reviewed-by:
-
Tomohiro Misono authored
Add new unprivileged ioctl BTRFS_IOC_GET_SUBVOL_INFO which returns the information of subvolume containing this inode. (i.e. returns the information in ROOT_ITEM and ROOT_BACKREF.) Reviewed-by:
-
- 30 May, 2018 24 commits
-
-
Omar Sandoval authored
btrfs_truncate() uses two variables for error handling, ret and err (if this sounds familiar, it's because btrfs_truncate_inode_items() did something similar). This is error prone, as was made evident by "Btrfs: fix error handling in btrfs_truncate()". We only have err because we don't want to mask an error if we call btrfs_update_inode() and btrfs_end_transaction(), so let's make that its own scoped return variable and use ret everywhere else. Reviewed-by:
Nikolay Borisov <nborisov@suse.com> Signed-off-by:
Omar Sandoval <osandov@fb.com> Signed-off-by:
-
Nikolay Borisov authored
Now that the read side is extracted into its own function, do the same to the write side. This leaves btrfs_get_blocks_direct_write with the sole purpose of handling common locking required. Also flip the condition in btrfs_get_blocks_direct_write so that the write case comes first and we check for if (Create) rather than if (!create). This is purely subjective but I believe makes reading a bit more "linear". No functional changes. Signed-off-by:
-
Nikolay Borisov authored
Currently this function handles both the READ and WRITE dio cases. This is facilitated by a bunch of 'if' statements, a goto short-circuit statement and a very perverse aliasing of "!created"(READ) case by setting lockstart = lockend and checking for lockstart < lockend for detecting the write. Let's simplify this mess by extracting the READ-only code into a separate __btrfs_get_block_direct_read function. This is only the first step, the next one will be to factor out the write side as well. The end goal will be to have the common locking/ unlocking code in btrfs_get_blocks_direct and then it will call either the read|write subvariants. No functional changes. Signed-off-by:
-
Su Yue authored
The error code does not match the reason of failure and may confuse the callers. Signed-off-by:
Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by:
-
Kees Cook authored
In the quest to remove all stack VLA usage from the kernel[1], this allocates the working buffers during regular init, instead of using stack space. This refactors the allocation code a bit to make it easier to review. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.comSigned-off-by:
Kees Cook <keescook@chromium.org> Reviewed-by:
-
Su Yue authored
In cow_file_range(), create_io_em() may fail, but its return value is not recorded. Then return value may be 0 even it failed which is a wrong behavior. Let cow_file_range() return PTR_ERR(em) if create_io_em() failed. Fixes: 6f9994db ("Btrfs: create a helper to create em for IO") CC: stable@vger.kernel.org # 4.11+ Signed-off-by:
-
Gu JinXiang authored
Since there is no more use of qgroup_reserved member in struct btrfs_pending_snapshot, remove it. Signed-off-by:
-
Gu JinXiang authored
Since commit 7775c818 ("btrfs: remove unused parameter from btrfs_subvolume_release_metadata") parameter qgroup_reserved is not used by caller of function btrfs_subvolume_reserve_metadata. So remove it. Signed-off-by:
-
Ethan Lien authored
[Problem description and how we fix it] We should balance dirty metadata pages at the end of btrfs_finish_ordered_io, since a small, unmergeable random write can potentially produce dirty metadata which is multiple times larger than the data itself. For example, a small, unmergeable 4KiB write may produce: 16KiB dirty leaf (and possibly 16KiB dirty node) in subvolume tree 16KiB dirty leaf (and possibly 16KiB dirty node) in checksum tree 16KiB dirty leaf (and possibly 16KiB dirty node) in extent tree Although we do call balance dirty pages in write side, but in the buffered write path, most metadata are dirtied only after we reach the dirty background limit (which by far only counts dirty data pages) and wakeup the flusher thread. If there are many small, unmergeable random writes spread in a large btree, we'll find a burst of dirty pages exceeds the dirty_bytes limit after we wakeup the flusher thread - which is not what we expect. In our machine, it caused out-of-memory problem since a page cannot be dropped if it is marked dirty. Someone may worry about we may sleep in btrfs_btree_balance_dirty_nodelay, but since we do btrfs_finish_ordered_io in a separate worker, it will not stop the flusher consuming dirty pages. Also, we use different worker for metadata writeback endio, sleep in btrfs_finish_ordered_io help us throttle the size of dirty metadata pages. [Reproduce steps] To reproduce the problem, we need to do 4KiB write randomly spread in a large btree. In our 2GiB RAM machine: 1) Create 4 subvolumes. 2) Run fio on each subvolume: [global] direct=0 rw=randwrite ioengine=libaio bs=4k iodepth=16 numjobs=1 group_reporting size=128G runtime=1800 norandommap time_based randrepeat=0 3) Take snapshot on each subvolume and repeat fio on existing files. 4) Repeat step (3) until we get large btrees. In our case, by observing btrfs_root_item->bytes_used, we have 2GiB of metadata in each subvolume tree and 12GiB of metadata in extent tree. 5) Stop all fio, take snapshot again, and wait until all delayed work is completed. 6) Start all fio. Few seconds later we hit OOM when the flusher starts to work. It can be reproduced even when using nocow write. Signed-off-by:Ethan Lien <ethanlien@synology.com> Reviewed-by:
-
Ethan Lien authored
In nocow path, we check if the extent is snapshotted in btrfs_cross_ref_exist(). We can do the similar check earlier and avoid unnecessary search into extent tree. A fio test on a Intel D-1531, 16GB RAM, SSD RAID-5 machine as follows: [global] group_reporting time_based thread=1 ioengine=libaio bs=4k iodepth=32 size=64G runtime=180 numjobs=8 rw=randwrite [file1] filename=/mnt/nocow/testfile IOPS result: unpatched patched 1 fio round: 46670 46958 snapshot 2 fio round: 51826 54498 3 fio round: 59767 61289 After snapshot, the first fio get about 5% performance gain. As we continually write to the same file, all writes will resume to nocow mode and eventually we have no performance gain. Signed-off-by:
-
Lu Fengqi authored
This function always takes a transaction handle which contains a reference to the fs_info. Use that and remove the extra argument. Signed-off-by:
-
Lu Fengqi authored
This function always takes a transaction handle which contains a reference to the fs_info. Use that and remove the extra argument. Signed-off-by:
-
Liu Bo authored
The check is superfluous since all callers who set search_for_commit also have skip_locking set. ASSERT() is put in place to ensure skip_locking is set by new callers. Reviewed-by:
Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by:
-
Liu Bo authored
As unlock_up() is written as for () { if (!path->locks[i]) break; ... if (... && path->locks[i]) { } } Apparently, @path->locks[i] is always true at this 'if'. Signed-off-by: -
Liu Bo authored
Typically, when acquiring root node's lock, btrfs tries its best to get read lock and trade for write lock if @write_lock_level implies to do so. In case of (cow && (p->keep_locks || p->lowest_level)), write_lock_level is set to BTRFS_MAX_LEVEL, which means we need to acquire root node's write lock directly. In this particular case, the dance of acquiring read lock and then trading for write lock can be saved. Signed-off-by:
-
Liu Bo authored
It's good to have a helper instead of having all get-root details open-coded. The new helper locks (if necessary) and sets root node of the path. Also invert the checks to make the code flow easier to read. There is no functional change in this commit. Signed-off-by:
-
Liu Bo authored
If parent_transid "0" is passed to btrfs_buffer_uptodate(), btrfs_buffer_uptodate() is equivalent to extent_buffer_uptodate(), but extent_buffer_uptodate() is preferred since we don't have to look into verify_parent_transid(). Signed-off-by:
-
Liu Bo authored
read_block_for_search() can be simplified as: tmp = find_extent_buffer(); if (tmp) return; ... free_extent_buffer(); read_tree_block(); Apparently, @tmp must be NULL at this point, free_extent_buffer() is not needed. Signed-off-by:
-
Lu Fengqi authored
Since commit dc2d3005 ("btrfs: remove dead create_space_info calls"), there is only one caller btrfs_init_space_info. However, it doesn't need create_space_info to return space_info at all. Signed-off-by:
-
Liu Bo authored
As verify_level_key() is checked after verify_parent_transid(), i.e. if (verify_parent_transid()) ret = -EIO; else if (verify_level_key()) ret = -EUCLEAN; if parent_transid is 0, verify_parent_transid() skips verifying parent_transid and considers eb as valid, and if verify_level_key() reports something wrong, we're not going to know if it's caused by corrupted metadata or non-checkecd eb (e.g. stale eb). The stale eb can be from an outdated raid1 mirror after a degraded mount, see eg "btrfs: fix reading stale metadata blocks after degraded raid1 mounts" (02a3307a) for more details. @parent_transid is able to tell whether the eb's generation has been verified by the caller. Signed-off-by:
-
Qu Wenruo authored
Error message from qgroup_rescan_init() mostly looks like: BTRFS info (device nvme0n1p1): qgroup_rescan_init failed with -115 Which is far from meaningful, and sometimes confusing as for above -EINPROGRESS it's mostly (despite the init race) harmless, but sometimes it can also indicate problem if the return value is -EINVAL. Change it to some more meaningful messages like: BTRFS info (device nvme0n1p1): qgroup rescan is already in progress And BTRFS err(device nvme0n1p1): qgroup rescan init failed, qgroup is not enabled Signed-off-by:
-
Omar Sandoval authored
If we have invalid flags set, when we error out we must drop our writer counter and free the buffer we allocated for the arguments. This bug is trivially reproduced with the following program on 4.7+: #include <fcntl.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/ioctl.h> #include <sys/stat.h> #include <sys/types.h> #include <linux/btrfs.h> #include <linux/btrfs_tree.h> int main(int argc, char **argv) { struct btrfs_ioctl_vol_args_v2 vol_args = { .flags = UINT64_MAX, }; int ret; int fd; if (argc != 2) { fprintf(stderr, "usage: %s PATH\n", argv[0]); return EXIT_FAILURE; } fd = open(argv[1], O_WRONLY); if (fd == -1) { perror("open"); return EXIT_FAILURE; } ret = ioctl(fd, BTRFS_IOC_RM_DEV_V2, &vol_args); if (ret == -1) perror("ioctl"); close(fd); return EXIT_SUCCESS; } When unmounting the filesystem, we'll hit the WARN_ON(mnt_get_writers(mnt)) in cleanup_mnt() and also may prevent the filesystem to be remounted read-only as the writer count will stay lifted. Fixes: 6b526ed7 ("btrfs: introduce device delete by devid") CC: stable@vger.kernel.org # 4.9+ Signed-off-by: -
Qu Wenruo authored
For inlined extent, we only have one segment, thus less things to check. And further more, inlined extent always has the csum in its leaf header, it's less probable to have corrupted data. Anyway, still check header and segment header. Signed-off-by:
-
Qu Wenruo authored
James Harvey reported that some corrupted compressed extent data can lead to various kernel memory corruption. Such corrupted extent data belongs to inode with NODATASUM flags, thus data csum won't help us detecting such bug. If lucky enough, KASAN could catch it like: BUG: KASAN: slab-out-of-bounds in lzo_decompress_bio+0x384/0x7a0 [btrfs] Write of size 4096 at addr ffff8800606cb0f8 by task kworker/u16:0/2338 CPU: 3 PID: 2338 Comm: kworker/u16:0 Tainted: G O 4.17.0-rc5-custom+ #50 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: btrfs-endio btrfs_endio_helper [btrfs] Call Trace: dump_stack+0xc2/0x16b print_address_description+0x6a/0x270 kasan_report+0x260/0x380 memcpy+0x34/0x50 lzo_decompress_bio+0x384/0x7a0 [btrfs] end_compressed_bio_read+0x99f/0x10b0 [btrfs] bio_endio+0x32e/0x640 normal_work_helper+0x15a/0xea0 [btrfs] process_one_work+0x7e3/0x1470 worker_thread+0x1b0/0x1170 kthread+0x2db/0x390 ret_from_fork+0x22/0x40 ... The offending compressed data has the following info: Header: length 32768 (looks completely valid) Segment 0 Header: length 3472882419 (obviously out of bounds) Then when handling segment 0, since it's over the current page, we need the copy the compressed data to temporary buffer in workspace, then such large size would trigger out-of-bounds memory access, screwing up the whole kernel. Fix it by adding extra checks on header and segment headers to ensure we won't access out-of-bounds, and even checks the decompressed data won't be out-of-bounds. Reported-by:
-
- 29 May, 2018 3 commits
-
-
Qu Wenruo authored
Although it's not that complex, but such comment could still save several minutes for newer reader/reviewer instead of inferring that from the code. Signed-off-by:
-
Qu Wenruo authored
Since compression.h is using the SZ_* macros, and if some file includes only compression.h without linux/sizes.h, it will cause compile error. One example is lzo.c, if it uses BTRFS_MAX_COMPRESSED. Fix it by adding linux/sizes.h in compression.h Signed-off-by:
-
Omar Sandoval authored
In btrfs_clone_files(), we must check the NODATASUM flag while the inodes are locked. Otherwise, it's possible that btrfs_ioctl_setflags() will change the flags after we check and we can end up with a party checksummed file. The race window is only a few instructions in size, between the if and the locks which is: 3834 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) 3835 return -EISDIR; where the setflags must be run and toggle the NODATASUM flag (provided the file size is 0). The clone will block on the inode lock, segflags takes the inode lock, changes flags, releases log and clone continues. Not impossible but still needs a lot of bad luck to hit unintentionally. Fixes: 0e7b824c ("Btrfs: don't make a file partly checksummed through file clone") CC: stable@vger.kernel.org # 4.4+ Signed-off-by:
-
