BMC/Intel-BMC/linux.git/fs/ext4, branch dev-5.15-intel

ext4: force overhead calculation if the s_overhead_cluster makes no sense

2022-04-27T12:39:01+00:00

commit 85d825dbf4899a69407338bae462a59aa9a37326 upstream. If the file system does not use bigalloc, calculating the overhead is cheap, so force the recalculation of the overhead so we don't have to trust the precalculated overhead in the superblock. Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix overhead calculation to account for the reserved gdt blocks

2022-04-27T12:39:01+00:00

commit 10b01ee92df52c8d7200afead4d5e5f55a5c58b1 upstream. The kernel calculation was underestimating the overhead by not taking into account the reserved gdt blocks. With this change, the overhead calculated by the kernel matches the overhead calculation in mke2fs. Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: limit length to bitmap_maxbytes - blocksize in punch_hole

2022-04-27T12:39:01+00:00

commit 2da376228a2427501feb9d15815a45dbdbdd753e upstream. Syzbot found an issue [1] in ext4_fallocate(). The C reproducer [2] calls fallocate(), passing size 0xffeffeff000ul, and offset 0x1000000ul, which, when added together exceed the bitmap_maxbytes for the inode. This triggers a BUG in ext4_ind_remove_space(). According to the comments in this function the 'end' parameter needs to be one block after the last block to be removed. In the case when the BUG is triggered it points to the last block. Modify the ext4_punch_hole() function and add constraint that caps the length to satisfy the one before laster block requirement. LINK: [1] https://syzkaller.appspot.com/bug?id=b80bd9cf348aac724a4f4dff251800106d721331 LINK: [2] https://syzkaller.appspot.com/text?tag=ReproC&x=14ba0238700000 Fixes: a4bb6b64e39a ("ext4: enable "punch hole" functionality") Reported-by: syzbot+7a806094edd5d07ba029@syzkaller.appspotmail.com Signed-off-by: Tadeusz Struk Link: https://lore.kernel.org/r/20220331200515.153214-1-tadeusz.struk@linaro.org Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix use-after-free in ext4_search_dir

2022-04-27T12:39:01+00:00

commit c186f0887fe7061a35cebef024550ec33ef8fbd8 upstream. We got issue as follows: EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue ================================================================== BUG: KASAN: use-after-free in ext4_search_dir fs/ext4/namei.c:1394 [inline] BUG: KASAN: use-after-free in search_dirblock fs/ext4/namei.c:1199 [inline] BUG: KASAN: use-after-free in __ext4_find_entry+0xdca/0x1210 fs/ext4/namei.c:1553 Read of size 1 at addr ffff8881317c3005 by task syz-executor117/2331 CPU: 1 PID: 2331 Comm: syz-executor117 Not tainted 5.10.0+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:83 [inline] dump_stack+0x144/0x187 lib/dump_stack.c:124 print_address_description+0x7d/0x630 mm/kasan/report.c:387 __kasan_report+0x132/0x190 mm/kasan/report.c:547 kasan_report+0x47/0x60 mm/kasan/report.c:564 ext4_search_dir fs/ext4/namei.c:1394 [inline] search_dirblock fs/ext4/namei.c:1199 [inline] __ext4_find_entry+0xdca/0x1210 fs/ext4/namei.c:1553 ext4_lookup_entry fs/ext4/namei.c:1622 [inline] ext4_lookup+0xb8/0x3a0 fs/ext4/namei.c:1690 __lookup_hash+0xc5/0x190 fs/namei.c:1451 do_rmdir+0x19e/0x310 fs/namei.c:3760 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x445e59 Code: 4d c7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 1b c7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff2277fac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 0000000000400280 RCX: 0000000000445e59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000002 R10: 00007fff2277f990 R11: 0000000000000246 R12: 0000000000000000 R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the page: page:0000000048cd3304 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x1317c3 flags: 0x200000000000000() raw: 0200000000000000 ffffea0004526588 ffffea0004528088 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881317c2f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881317c2f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881317c3000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881317c3080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881317c3100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ext4_search_dir: ... de = (struct ext4_dir_entry_2 *)search_buf; dlimit = search_buf + buf_size; while ((char *) de < dlimit) { ... if ((char *) de + de->name_len <= dlimit && ext4_match(dir, fname, de)) { ... } ... de_len = ext4_rec_len_from_disk(de->rec_len, dir->i_sb->s_blocksize); if (de_len <= 0) return -1; offset += de_len; de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); } Assume: de=0xffff8881317c2fff dlimit=0x0xffff8881317c3000 If read 'de->name_len' which address is 0xffff8881317c3005, obviously is out of range, then will trigger use-after-free. To solve this issue, 'dlimit' must reserve 8 bytes, as we will read 'de->name_len' to judge if '(char *) de + de->name_len' out of range. Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220324064816.1209985-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: fix symlink file size not match to file content

2022-04-27T12:39:01+00:00

commit a2b0b205d125f27cddfb4f7280e39affdaf46686 upstream. We got issue as follows: [home]# fsck.ext4 -fn ram0yb e2fsck 1.45.6 (20-Mar-2020) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Symlink /p3/d14/d1a/l3d (inode #3494) is invalid. Clear? no Entry 'l3d' in /p3/d14/d1a (3383) has an incorrect filetype (was 7, should be 0). Fix? no As the symlink file size does not match the file content. If the writeback of the symlink data block failed, ext4_finish_bio() handles the end of IO. However this function fails to mark the buffer with BH_write_io_error and so when unmount does journal checkpoint it cannot detect the writeback error and will cleanup the journal. Thus we've lost the correct data in the journal area. To solve this issue, mark the buffer as BH_write_io_error in ext4_finish_bio(). Cc: stable@kernel.org Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220321144438.201685-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix fallocate to use file_modified to update permissions consistently

2022-04-27T12:39:01+00:00

commit ad5cd4f4ee4d5fcdb1bfb7a0c073072961e70783 upstream. Since the initial introduction of (posix) fallocate back at the turn of the century, it has been possible to use this syscall to change the user-visible contents of files. This can happen by extending the file size during a preallocation, or through any of the newer modes (punch, zero, collapse, insert range). Because the call can be used to change file contents, we should treat it like we do any other modification to a file -- update the mtime, and drop set[ug]id privileges/capabilities. The VFS function file_modified() does all this for us if pass it a locked inode, so let's make fallocate drop permissions correctly. Signed-off-by: Darrick J. Wong Link: https://lore.kernel.org/r/20220308185043.GA117678@magnolia Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

ext4: don't BUG if someone dirty pages without asking ext4 first

2022-04-08T12:23:57+00:00

[ Upstream commit cc5095747edfb054ca2068d01af20be3fcc3634f ] [un]pin_user_pages_remote is dirtying pages without properly warning the file system in advance. A related race was noted by Jan Kara in 2018[1]; however, more recently instead of it being a very hard-to-hit race, it could be reliably triggered by process_vm_writev(2) which was discovered by Syzbot[2]. This is technically a bug in mm/gup.c, but arguably ext4 is fragile in that if some other kernel subsystem dirty pages without properly notifying the file system using page_mkwrite(), ext4 will BUG, while other file systems will not BUG (although data will still be lost). So instead of crashing with a BUG, issue a warning (since there may be potential data loss) and just mark the page as clean to avoid unprivileged denial of service attacks until the problem can be properly fixed. More discussion and background can be found in the thread starting at [2]. [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com Reported-by: syzbot+d59332e2db681cf18f0318a06e994ebbb529a8db@syzkaller.appspotmail.com Reported-by: Lee Jones Signed-off-by: Theodore Ts'o Link: https://lore.kernel.org/r/YiDS9wVfq4mM2jGK@mit.edu Signed-off-by: Sasha Levin

ext4: fix ext4_mb_mark_bb() with flex_bg with fast_commit

2022-04-08T12:23:57+00:00

[ Upstream commit bfdc502a4a4c058bf4cbb1df0c297761d528f54d ] In case of flex_bg feature (which is by default enabled), extents for any given inode might span across blocks from two different block group. ext4_mb_mark_bb() only reads the buffer_head of block bitmap once for the starting block group, but it fails to read it again when the extent length boundary overflows to another block group. Then in this below loop it accesses memory beyond the block group bitmap buffer_head and results into a data abort. for (i = 0; i < clen; i++) if (!mb_test_bit(blkoff + i, bitmap_bh->b_data) == !state) already++; This patch adds this functionality for checking block group boundary in ext4_mb_mark_bb() and update the buffer_head(bitmap_bh) for every different block group. w/o this patch, I was easily able to hit a data access abort using Power platform. <...> [ 74.327662] EXT4-fs error (device loop3): ext4_mb_generate_buddy:1141: group 11, block bitmap and bg descriptor inconsistent: 21248 vs 23294 free clusters [ 74.533214] EXT4-fs (loop3): shut down requested (2) [ 74.536705] Aborting journal on device loop3-8. [ 74.702705] BUG: Unable to handle kernel data access on read at 0xc00000005e980000 [ 74.703727] Faulting instruction address: 0xc0000000007bffb8 cpu 0xd: Vector: 300 (Data Access) at [c000000015db7060] pc: c0000000007bffb8: ext4_mb_mark_bb+0x198/0x5a0 lr: c0000000007bfeec: ext4_mb_mark_bb+0xcc/0x5a0 sp: c000000015db7300 msr: 800000000280b033 dar: c00000005e980000 dsisr: 40000000 current = 0xc000000027af6880 paca = 0xc00000003ffd5200 irqmask: 0x03 irq_happened: 0x01 pid = 5167, comm = mount <...> enter ? for help [c000000015db7380] c000000000782708 ext4_ext_clear_bb+0x378/0x410 [c000000015db7400] c000000000813f14 ext4_fc_replay+0x1794/0x2000 [c000000015db7580] c000000000833f7c do_one_pass+0xe9c/0x12a0 [c000000015db7710] c000000000834504 jbd2_journal_recover+0x184/0x2d0 [c000000015db77c0] c000000000841398 jbd2_journal_load+0x188/0x4a0 [c000000015db7880] c000000000804de8 ext4_fill_super+0x2638/0x3e10 [c000000015db7a40] c0000000005f8404 get_tree_bdev+0x2b4/0x350 [c000000015db7ae0] c0000000007ef058 ext4_get_tree+0x28/0x40 [c000000015db7b00] c0000000005f6344 vfs_get_tree+0x44/0x100 [c000000015db7b70] c00000000063c408 path_mount+0xdd8/0xe70 [c000000015db7c40] c00000000063c8f0 sys_mount+0x450/0x550 [c000000015db7d50] c000000000035770 system_call_exception+0x4a0/0x4e0 [c000000015db7e10] c00000000000c74c system_call_common+0xec/0x250 Signed-off-by: Ritesh Harjani Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/2609bc8f66fc15870616ee416a18a3d392a209c4.1644992609.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: correct cluster len and clusters changed accounting in ext4_mb_mark_bb

2022-04-08T12:23:57+00:00

[ Upstream commit a5c0e2fdf7cea535ba03259894dc184e5a4c2800 ] ext4_mb_mark_bb() currently wrongly calculates cluster len (clen) and flex_group->free_clusters. This patch fixes that. Identified based on code review of ext4_mb_mark_bb() function. Signed-off-by: Ritesh Harjani Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/a0b035d536bafa88110b74456853774b64c8ac40.1644992609.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: make mb_optimize_scan performance mount option work with extents

2022-04-08T12:22:59+00:00

commit 077d0c2c78df6f7260cdd015a991327efa44d8ad upstream. Currently mb_optimize_scan scan feature which improves filesystem performance heavily (when FS is fragmented), seems to be not working with files with extents (ext4 by default has files with extents). This patch fixes that and makes mb_optimize_scan feature work for files with extents. Below are some performance numbers obtained when allocating a 10M and 100M file with and w/o this patch on a filesytem with no 1M contiguous block. =============== Workload: dd if=/dev/urandom of=test conv=fsync bs=1M count=10/100 Time taken ===================================================== no. Size without-patch with-patch Diff(%) 1 10M 0m8.401s 0m5.623s 33.06% 2 100M 1m40.465s 1m14.737s 25.6% ============= w/o patch: mballoc: reqs: 17056 success: 11407 groups_scanned: 13643 cr0_stats: hits: 37 groups_considered: 9472 useless_loops: 36 bad_suggestions: 0 cr1_stats: hits: 11418 groups_considered: 908560 useless_loops: 1894 bad_suggestions: 0 cr2_stats: hits: 1873 groups_considered: 6913 useless_loops: 21 cr3_stats: hits: 21 groups_considered: 5040 useless_loops: 21 extents_scanned: 417364 goal_hits: 3707 2^n_hits: 37 breaks: 1873 lost: 0 buddies_generated: 239/240 buddies_time_used: 651080 preallocated: 705 discarded: 478 with patch: mballoc: reqs: 12768 success: 11305 groups_scanned: 12768 cr0_stats: hits: 1 groups_considered: 18 useless_loops: 0 bad_suggestions: 0 cr1_stats: hits: 5829 groups_considered: 50626 useless_loops: 0 bad_suggestions: 0 cr2_stats: hits: 6938 groups_considered: 580363 useless_loops: 0 cr3_stats: hits: 0 groups_considered: 0 useless_loops: 0 extents_scanned: 309059 goal_hits: 0 2^n_hits: 1 breaks: 1463 lost: 0 buddies_generated: 239/240 buddies_time_used: 791392 preallocated: 673 discarded: 446 Fixes: 196e402 (ext4: improve cr 0 / cr 1 group scanning) Cc: stable@kernel.org Reported-by: Geetika Moolchandani Reported-by: Nageswara R Sastry Suggested-by: Ritesh Harjani Signed-off-by: Ojaswin Mujoo Link: https://lore.kernel.org/r/fc9a48f7f8dcfc83891a8b21f6dd8cdf056ed810.1646732698.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman