kernel.git/fs/hfs, branch linux-4.4.y

hfs: add lock nesting notation to hfs_find_init

2021-08-04T09:56:45Z

[ Upstream commit b3b2177a2d795e35dc11597b2609eb1e7e57e570 ] Syzbot reports a possible recursive lock in [1]. This happens due to missing lock nesting information. From the logs, we see that a call to hfs_fill_super is made to mount the hfs filesystem. While searching for the root inode, the lock on the catalog btree is grabbed. Then, when the parent of the root isn't found, a call to __hfs_bnode_create is made to create the parent of the root. This eventually leads to a call to hfs_ext_read_extent which grabs a lock on the extents btree. Since the order of locking is catalog btree -> extents btree, this lock hierarchy does not lead to a deadlock. To tell lockdep that this locking is safe, we add nesting notation to distinguish between catalog btrees, extents btrees, and attributes btrees (for HFS+). This has already been done in hfsplus. Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1] Link: https://lkml.kernel.org/r/20210701030756.58760-4-desmondcheongzx@gmail.com Signed-off-by: Desmond Cheong Zhi Xi Reported-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com Tested-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com Reviewed-by: Viacheslav Dubeyko Cc: Al Viro Cc: Greg Kroah-Hartman Cc: Gustavo A. R. Silva Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: fix high memory mapping in hfs_bnode_read

2021-08-04T09:56:45Z

[ Upstream commit 54a5ead6f5e2b47131a7385d0c0af18e7b89cb02 ] Pages that we read in hfs_bnode_read need to be kmapped into kernel address space. However, currently only the 0th page is kmapped. If the given offset + length exceeds this 0th page, then we have an invalid memory access. To fix this, we kmap relevant pages one by one and copy their relevant portions of data. An example of invalid memory access occurring without this fix can be seen in the following crash report: ================================================================== BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline] BUG: KASAN: use-after-free in hfs_bnode_read+0xc4/0xe0 fs/hfs/bnode.c:26 Read of size 2 at addr ffff888125fdcffe by task syz-executor5/4634 CPU: 0 PID: 4634 Comm: syz-executor5 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x195/0x1f8 lib/dump_stack.c:120 print_address_description.constprop.0+0x1d/0x110 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7b/0xd4 mm/kasan/report.c:436 check_region_inline mm/kasan/generic.c:180 [inline] kasan_check_range+0x154/0x1b0 mm/kasan/generic.c:186 memcpy+0x24/0x60 mm/kasan/shadow.c:65 memcpy include/linux/fortify-string.h:191 [inline] hfs_bnode_read+0xc4/0xe0 fs/hfs/bnode.c:26 hfs_bnode_read_u16 fs/hfs/bnode.c:34 [inline] hfs_bnode_find+0x880/0xcc0 fs/hfs/bnode.c:365 hfs_brec_find+0x2d8/0x540 fs/hfs/bfind.c:126 hfs_brec_read+0x27/0x120 fs/hfs/bfind.c:165 hfs_cat_find_brec+0x19a/0x3b0 fs/hfs/catalog.c:194 hfs_fill_super+0xc13/0x1460 fs/hfs/super.c:419 mount_bdev+0x331/0x3f0 fs/super.c:1368 hfs_mount+0x35/0x40 fs/hfs/super.c:457 legacy_get_tree+0x10c/0x220 fs/fs_context.c:592 vfs_get_tree+0x93/0x300 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x13f5/0x20e0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount fs/namespace.c:3433 [inline] __x64_sys_mount+0x2b8/0x340 fs/namespace.c:3433 do_syscall_64+0x37/0xc0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x45e63a Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 88 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9404d410d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000248 RCX: 000000000045e63a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f9404d41120 RBP: 00007f9404d41120 R08: 00000000200002c0 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000003 R14: 00000000004ad5d8 R15: 0000000000000000 The buggy address belongs to the page: page:00000000dadbcf3e refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x125fdc flags: 0x2fffc0000000000(node=0|zone=2|lastcpupid=0x3fff) raw: 02fffc0000000000 ffffea000497f748 ffffea000497f6c8 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888125fdce80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888125fdcf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888125fdcf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888125fdd000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888125fdd080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Link: https://lkml.kernel.org/r/20210701030756.58760-3-desmondcheongzx@gmail.com Signed-off-by: Desmond Cheong Zhi Xi Reviewed-by: Viacheslav Dubeyko Cc: Al Viro Cc: Greg Kroah-Hartman Cc: Gustavo A. R. Silva Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: add missing clean-up in hfs_fill_super

2021-08-04T09:56:45Z

[ Upstream commit 16ee572eaf0d09daa4c8a755fdb71e40dbf8562d ] Patch series "hfs: fix various errors", v2. This series ultimately aims to address a lockdep warning in hfs_find_init reported by Syzbot [1]. The work done for this led to the discovery of another bug, and the Syzkaller repro test also reveals an invalid memory access error after clearing the lockdep warning. Hence, this series is broken up into three patches: 1. Add a missing call to hfs_find_exit for an error path in hfs_fill_super 2. Fix memory mapping in hfs_bnode_read by fixing calls to kmap 3. Add lock nesting notation to tell lockdep that the observed locking hierarchy is safe This patch (of 3): Before exiting hfs_fill_super, the struct hfs_find_data used in hfs_find_init should be passed to hfs_find_exit to be cleaned up, and to release the lock held on the btree. The call to hfs_find_exit is missing from an error path. We add it back in by consolidating calls to hfs_find_exit for error paths. Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1] Link: https://lkml.kernel.org/r/20210701030756.58760-1-desmondcheongzx@gmail.com Link: https://lkml.kernel.org/r/20210701030756.58760-2-desmondcheongzx@gmail.com Signed-off-by: Desmond Cheong Zhi Xi Reviewed-by: Viacheslav Dubeyko Cc: Gustavo A. R. Silva Cc: Al Viro Cc: Shuah Khan Cc: Greg Kroah-Hartman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

fs/hfs/extent.c: fix array out of bounds read of array extent

2019-11-28T17:25:57Z

[ Upstream commit 6c9a3f843a29d6894dfc40df338b91dbd78f0ae3 ] Currently extent and index i are both being incremented causing an array out of bounds read on extent[i]. Fix this by removing the extraneous increment of extent. Ernesto said: : This is only triggered when deleting a file with a resource fork. I : may be wrong because the documentation isn't clear, but I don't think : you can create those under linux. So I guess nobody was testing them. : : > A disk space leak, perhaps? : : That's what it looks like in general. hfs_free_extents() won't do : anything if the block count doesn't add up, and the error will be : ignored. Now, if the block count randomly does add up, we could see : some corruption. Detected by CoverityScan, CID#711541 ("Out of bounds read") Link: http://lkml.kernel.org/r/20180831140538.31566-1-colin.king@canonical.com Signed-off-by: Colin Ian King Reviewed-by: Ernesto A. Fernndez Cc: David Howells Cc: Al Viro Cc: Hin-Tak Leung Cc: Vyacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: fix return value of hfs_get_block()

2019-11-28T17:25:57Z

[ Upstream commit 1267a07be5ebbff2d2739290f3d043ae137c15b4 ] Direct writes to empty inodes fail with EIO. The generic direct-io code is in part to blame (a patch has been submitted as "direct-io: allow direct writes to empty inodes"), but hfs is worse affected than the other filesystems because the fallback to buffered I/O doesn't happen. The problem is the return value of hfs_get_block() when called with !create. Change it to be more consistent with the other modules. Link: http://lkml.kernel.org/r/4538ab8c35ea37338490525f0f24cbc37227528c.1539195310.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Reviewed-by: Vyacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: prevent btree data loss on ENOSPC

2019-11-28T17:25:55Z

[ Upstream commit 54640c7502e5ed41fbf4eedd499e85f9acc9698f ] Inserting a new record in a btree may require splitting several of its nodes. If we hit ENOSPC halfway through, the new nodes will be left orphaned and their records will be lost. This could mean lost inodes or extents. Henceforth, check the available disk space before making any changes. This still leaves the potential problem of corruption on ENOMEM. There is no need to reserve space before deleting a catalog record, as we do for hfsplus. This difference is because hfs index nodes have fixed length keys. Link: http://lkml.kernel.org/r/ab5fc8a7d5ffccfd5f27b1cf2cb4ceb6c110da74.1536269131.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: fix BUG on bnode parent update

2019-11-28T17:25:55Z

[ Upstream commit ef75bcc5763d130451a99825f247d301088b790b ] hfs_brec_update_parent() may hit BUG_ON() if the first record of both a leaf node and its parent are changed, and if this forces the parent to be split. It is not possible for this to happen on a valid hfs filesystem because the index nodes have fixed length keys. For reasons I ignore, the hfs module does have support for a number of hfsplus features. A corrupt btree header may report variable length keys and trigger this BUG, so it's better to fix it. Link: http://lkml.kernel.org/r/cf9b02d57f806217a2b1bf5db8c3e39730d8f603.1535682463.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Reviewed-by: Andrew Morton Cc: Christoph Hellwig Cc: Viacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: do not free node before using

2018-12-17T20:55:12Z

[ Upstream commit ce96a407adef126870b3f4a1b73529dd8aa80f49 ] hfs_bmap_free() frees the node via hfs_bnode_put(node). However, it then reads node->this when dumping error message on an error path, which may result in a use-after-free bug. This patch frees the node only when it is never again used. Link: http://lkml.kernel.org/r/1542963889-128825-1-git-send-email-bianpan2016@163.com Fixes: a1185ffa2fc ("HFS rewrite") Signed-off-by: Pan Bian Reviewed-by: Andrew Morton Cc: Joe Perches Cc: Ernesto A. Fernandez Cc: Viacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: prevent btree data loss on root split

2018-11-27T15:08:00Z

[ Upstream commit d057c036672f33d43a5f7344acbb08cf3a8a0c09 ] This bug is triggered whenever hfs_brec_update_parent() needs to split the root node. The height of the btree is not increased, which leaves the new node orphaned and its records lost. It is not possible for this to happen on a valid hfs filesystem because the index nodes have fixed length keys. For reasons I ignore, the hfs module does have support for a number of hfsplus features. A corrupt btree header may report variable length keys and trigger this bug, so it's better to fix it. Link: http://lkml.kernel.org/r/9750b1415685c4adca10766895f6d5ef12babdb0.1535682463.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: prevent crash on exit from failed search

2018-09-15T07:40:37Z

[ Upstream commit dc2572791d3a41bab94400af2b6bca9d71ccd303 ] hfs_find_exit() expects fd->bnode to be NULL after a search has failed. hfs_brec_insert() may instead set it to an error-valued pointer. Fix this to prevent a crash. Link: http://lkml.kernel.org/r/53d9749a029c41b4016c495fc5838c9dba3afc52.1530294815.git.ernesto.mnd.fernandez@gmail.com Signed-off-by: Ernesto A. Fernández Cc: Anatoly Trosinenko Cc: Viacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman