cifs: use cifsInodeInfo->open_file_lock while iterating to avoid a panic

Commit 487317c994 ("cifs: add spinlock for the openFileList to
cifsInodeInfo") added cifsInodeInfo->open_file_lock spin_lock to protect
the openFileList, but missed a few places where cifs_inode->openFileList
was enumerated.  Change these remaining tcon->open_file_lock to
cifsInodeInfo->open_file_lock to avoid panic in is_size_safe_to_change.

[17313.245641] RIP: 0010:is_size_safe_to_change+0x57/0xb0 [cifs]
[17313.245645] Code: 68 40 48 89 ef e8 19 67 b7 f1 48 8b 43 40 48 8d 4b 40 48 8d 50 f0 48 39 c1 75 0f eb 47 48 8b 42 10 48 8d 50 f0 48 39 c1 74 3a <8b> 80 88 00 00 00 83 c0 01 a8 02 74 e6 48 89 ef c6 07 00 0f 1f 40
[17313.245649] RSP: 0018:ffff94ae1baefa30 EFLAGS: 00010202
[17313.245654] RAX: dead000000000100 RBX: ffff88dc72243300 RCX: ffff88dc72243340
[17313.245657] RDX: dead0000000000f0 RSI: 00000000098f7940 RDI: ffff88dd3102f040
[17313.245659] RBP: ffff88dd3102f040 R08: 0000000000000000 R09: ffff94ae1baefc40
[17313.245661] R10: ffffcdc8bb1c4e80 R11: ffffcdc8b50adb08 R12: 00000000098f7940
[17313.245663] R13: ffff88dc72243300 R14: ffff88dbc8f19600 R15: ffff88dc72243428
[17313.245667] FS:  00007fb145485700(0000) GS:ffff88dd3e000000(0000) knlGS:0000000000000000
[17313.245670] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[17313.245672] CR2: 0000026bb46c6000 CR3: 0000004edb110003 CR4: 00000000007606e0
[17313.245753] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[17313.245756] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[17313.245759] PKRU: 55555554
[17313.245761] Call Trace:
[17313.245803]  cifs_fattr_to_inode+0x16b/0x580 [cifs]
[17313.245838]  cifs_get_inode_info+0x35c/0xa60 [cifs]
[17313.245852]  ? kmem_cache_alloc_trace+0x151/0x1d0
[17313.245885]  cifs_open+0x38f/0x990 [cifs]
[17313.245921]  ? cifs_revalidate_dentry_attr+0x3e/0x350 [cifs]
[17313.245953]  ? cifsFileInfo_get+0x30/0x30 [cifs]
[17313.245960]  ? do_dentry_open+0x132/0x330
[17313.245963]  do_dentry_open+0x132/0x330
[17313.245969]  path_openat+0x573/0x14d0
[17313.245974]  do_filp_open+0x93/0x100
[17313.245979]  ? __check_object_size+0xa3/0x181
[17313.245986]  ? audit_alloc_name+0x7e/0xd0
[17313.245992]  do_sys_open+0x184/0x220
[17313.245999]  do_syscall_64+0x5b/0x1b0

Fixes: 487317c994 ("cifs: add spinlock for the openFileList to cifsInodeInfo")

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Dave Wysochanski 2019-10-03 15:16:27 +10:00 committed by Steve French
parent dd19c106a3
commit cb248819d2

View File

@ -1840,13 +1840,12 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
{ {
struct cifsFileInfo *open_file = NULL; struct cifsFileInfo *open_file = NULL;
struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb); struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
/* only filter by fsuid on multiuser mounts */ /* only filter by fsuid on multiuser mounts */
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER)) if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
fsuid_only = false; fsuid_only = false;
spin_lock(&tcon->open_file_lock); spin_lock(&cifs_inode->open_file_lock);
/* we could simply get the first_list_entry since write-only entries /* we could simply get the first_list_entry since write-only entries
are always at the end of the list but since the first entry might are always at the end of the list but since the first entry might
have a close pending, we go through the whole list */ have a close pending, we go through the whole list */
@ -1858,7 +1857,7 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
/* found a good file */ /* found a good file */
/* lock it so it will not be closed on us */ /* lock it so it will not be closed on us */
cifsFileInfo_get(open_file); cifsFileInfo_get(open_file);
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
return open_file; return open_file;
} /* else might as well continue, and look for } /* else might as well continue, and look for
another, or simply have the caller reopen it another, or simply have the caller reopen it
@ -1866,7 +1865,7 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
} else /* write only file */ } else /* write only file */
break; /* write only files are last so must be done */ break; /* write only files are last so must be done */
} }
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
return NULL; return NULL;
} }
@ -1877,7 +1876,6 @@ cifs_get_writable_file(struct cifsInodeInfo *cifs_inode, bool fsuid_only,
{ {
struct cifsFileInfo *open_file, *inv_file = NULL; struct cifsFileInfo *open_file, *inv_file = NULL;
struct cifs_sb_info *cifs_sb; struct cifs_sb_info *cifs_sb;
struct cifs_tcon *tcon;
bool any_available = false; bool any_available = false;
int rc = -EBADF; int rc = -EBADF;
unsigned int refind = 0; unsigned int refind = 0;
@ -1897,16 +1895,15 @@ cifs_get_writable_file(struct cifsInodeInfo *cifs_inode, bool fsuid_only,
} }
cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb); cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
tcon = cifs_sb_master_tcon(cifs_sb);
/* only filter by fsuid on multiuser mounts */ /* only filter by fsuid on multiuser mounts */
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER)) if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
fsuid_only = false; fsuid_only = false;
spin_lock(&tcon->open_file_lock); spin_lock(&cifs_inode->open_file_lock);
refind_writable: refind_writable:
if (refind > MAX_REOPEN_ATT) { if (refind > MAX_REOPEN_ATT) {
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
return rc; return rc;
} }
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
@ -1918,7 +1915,7 @@ refind_writable:
if (!open_file->invalidHandle) { if (!open_file->invalidHandle) {
/* found a good writable file */ /* found a good writable file */
cifsFileInfo_get(open_file); cifsFileInfo_get(open_file);
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
*ret_file = open_file; *ret_file = open_file;
return 0; return 0;
} else { } else {
@ -1938,7 +1935,7 @@ refind_writable:
cifsFileInfo_get(inv_file); cifsFileInfo_get(inv_file);
} }
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
if (inv_file) { if (inv_file) {
rc = cifs_reopen_file(inv_file, false); rc = cifs_reopen_file(inv_file, false);
@ -1953,7 +1950,7 @@ refind_writable:
cifsFileInfo_put(inv_file); cifsFileInfo_put(inv_file);
++refind; ++refind;
inv_file = NULL; inv_file = NULL;
spin_lock(&tcon->open_file_lock); spin_lock(&cifs_inode->open_file_lock);
goto refind_writable; goto refind_writable;
} }
@ -4461,17 +4458,15 @@ static int cifs_readpage(struct file *file, struct page *page)
static int is_inode_writable(struct cifsInodeInfo *cifs_inode) static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
{ {
struct cifsFileInfo *open_file; struct cifsFileInfo *open_file;
struct cifs_tcon *tcon =
cifs_sb_master_tcon(CIFS_SB(cifs_inode->vfs_inode.i_sb));
spin_lock(&tcon->open_file_lock); spin_lock(&cifs_inode->open_file_lock);
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) { if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
return 1; return 1;
} }
} }
spin_unlock(&tcon->open_file_lock); spin_unlock(&cifs_inode->open_file_lock);
return 0; return 0;
} }