01bce099af
[ Upstream commit ec4535b2a1d709d3a1fbec26739c672f13c98a7b ] cifs_get_fattr() may be called with a NULL inode, so check for a non-NULL inode before calling cifs_mark_open_handles_for_deleted_file(). This fixes the following oops: mount.cifs //srv/share /mnt -o ...,vers=3.1.1 cd /mnt touch foo; tail -f foo & rm foo cat foo BUG: kernel NULL pointer dereference, address: 00000000000005c0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 2 PID: 696 Comm: cat Not tainted 6.9.0-rc2 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:__lock_acquire+0x5d/0x1c70 Code: 00 00 44 8b a4 24 a0 00 00 00 45 85 f6 0f 84 bb 06 00 00 8b 2d 48 e2 95 01 45 89 c3 41 89 d2 45 89 c8 85 ed 0 0 <48> 81 3f 40 7a 76 83 44 0f 44 d8 83 fe 01 0f 86 1b 03 00 00 31 d2 RSP: 0018:ffffc90000b37490 EFLAGS: 00010002 RAX: 0000000000000000 RBX: ffff888110021ec0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000005c0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000200 FS: 00007f2a1fa08740(0000) GS:ffff888157a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000005c0 CR3: 000000011ac7c000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> ? __die+0x23/0x70 ? page_fault_oops+0x180/0x490 ? srso_alias_return_thunk+0x5/0xfbef5 ? exc_page_fault+0x70/0x230 ? asm_exc_page_fault+0x26/0x30 ? __lock_acquire+0x5d/0x1c70 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 lock_acquire+0xc0/0x2d0 ? cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs] ? srso_alias_return_thunk+0x5/0xfbef5 ? kmem_cache_alloc+0x2d9/0x370 _raw_spin_lock+0x34/0x80 ? cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs] cifs_mark_open_handles_for_deleted_file+0x3a/0x100 [cifs] cifs_get_fattr+0x24c/0x940 [cifs] ? srso_alias_return_thunk+0x5/0xfbef5 cifs_get_inode_info+0x96/0x120 [cifs] cifs_lookup+0x16e/0x800 [cifs] cifs_atomic_open+0xc7/0x5d0 [cifs] ? lookup_open.isra.0+0x3ce/0x5f0 ? __pfx_cifs_atomic_open+0x10/0x10 [cifs] lookup_open.isra.0+0x3ce/0x5f0 path_openat+0x42b/0xc30 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 do_filp_open+0xc4/0x170 do_sys_openat2+0xab/0xe0 __x64_sys_openat+0x57/0xa0 do_syscall_64+0xc1/0x1e0 entry_SYSCALL_64_after_hwframe+0x72/0x7a Fixes: ffceb7640cbf ("smb: client: do not defer close open handles to deleted files") Reviewed-by: Meetakshi Setiya <msetiya@microsoft.com> Reviewed-by: Bharath SM <bharathsm@microsoft.com> Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.