kernel/git/stable/linux.git/net/9p/client.c, branch linux-6.10.y

Merge tag '9p-for-6.10-rc2' of https://github.com/martinetd/linux

2024-05-29T16:25:15+00:00

Pull 9p fixes from Dominique Martinet: "Two fixes headed to stable trees: - a trace event was dumping uninitialized values - a missing lock that was thought to have exclusive access, and it turned out not to" * tag '9p-for-6.10-rc2' of https://github.com/martinetd/linux: 9p: add missing locking around taking dentry fid list net/9p: fix uninit-value in p9_client_rpc()

net/9p: fix uninit-value in p9_client_rpc()

2024-05-21T12:27:28+00:00

Syzbot with the help of KMSAN reported the following error: BUG: KMSAN: uninit-value in trace_9p_client_res include/trace/events/9p.h:146 [inline] BUG: KMSAN: uninit-value in p9_client_rpc+0x1314/0x1340 net/9p/client.c:754 trace_9p_client_res include/trace/events/9p.h:146 [inline] p9_client_rpc+0x1314/0x1340 net/9p/client.c:754 p9_client_create+0x1551/0x1ff0 net/9p/client.c:1031 v9fs_session_init+0x1b9/0x28e0 fs/9p/v9fs.c:410 v9fs_mount+0xe2/0x12b0 fs/9p/vfs_super.c:122 legacy_get_tree+0x114/0x290 fs/fs_context.c:662 vfs_get_tree+0xa7/0x570 fs/super.c:1797 do_new_mount+0x71f/0x15e0 fs/namespace.c:3352 path_mount+0x742/0x1f20 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x725/0x810 fs/namespace.c:3875 __x64_sys_mount+0xe4/0x150 fs/namespace.c:3875 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit was created at: __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2175 [inline] allocate_slab mm/slub.c:2338 [inline] new_slab+0x2de/0x1400 mm/slub.c:2391 ___slab_alloc+0x1184/0x33d0 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc+0x6d3/0xbe0 mm/slub.c:3852 p9_tag_alloc net/9p/client.c:278 [inline] p9_client_prepare_req+0x20a/0x1770 net/9p/client.c:641 p9_client_rpc+0x27e/0x1340 net/9p/client.c:688 p9_client_create+0x1551/0x1ff0 net/9p/client.c:1031 v9fs_session_init+0x1b9/0x28e0 fs/9p/v9fs.c:410 v9fs_mount+0xe2/0x12b0 fs/9p/vfs_super.c:122 legacy_get_tree+0x114/0x290 fs/fs_context.c:662 vfs_get_tree+0xa7/0x570 fs/super.c:1797 do_new_mount+0x71f/0x15e0 fs/namespace.c:3352 path_mount+0x742/0x1f20 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x725/0x810 fs/namespace.c:3875 __x64_sys_mount+0xe4/0x150 fs/namespace.c:3875 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 If p9_check_errors() fails early in p9_client_rpc(), req->rc.tag will not be properly initialized. However, trace_9p_client_res() ends up trying to print it out anyway before p9_client_rpc() finishes. Fix this issue by assigning default values to p9_fcall fields such as 'tag' and (just in case KMSAN unearths something new) 'id' during the tag allocation stage. Reported-and-tested-by: syzbot+ff14db38f56329ef68df@syzkaller.appspotmail.com Fixes: 348b59012e5c ("net/9p: Convert net/9p protocol dumps to tracepoints") Signed-off-by: Nikita Zhandarovich Reviewed-by: Christian Schoenebeck Cc: stable@vger.kernel.org Message-ID: <20240408141039.30428-1-n.zhandarovich@fintech.ru> Signed-off-by: Dominique Martinet

netfs, 9p: Implement helpers for new write code

2024-05-01T17:07:37+00:00

Implement the helpers for the new write code in 9p. There's now an optional ->prepare_write() that allows the filesystem to set the parameters for the next write, such as maximum size and maximum segment count, and an ->issue_write() that is called to initiate an (asynchronous) write operation. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: Christian Schoenebeck cc: v9fs@lists.linux.dev cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org

9p: Fix read/write debug statements to report server reply

2024-02-12T12:18:54+00:00

Previous conversion to iov missed these debug statements which would now always print the requested size instead of the actual server reply. Write also added a loop in a much older commit but we didn't report these, while reads do report each iteration -- it's more coherent to keep reporting all requests to server so move that at the same time. Fixes: 7f02464739da ("9p: convert to advancing variant of iov_iter_get_pages_alloc()") Signed-off-by: Dominique Martinet Message-ID: <20240109-9p-rw-trace-v1-1-327178114257@codewreck.org>

9p/net: fix possible memory leak in p9_check_errors()

2023-10-27T03:44:13+00:00

When p9pdu_readf() is called with "s?d" attribute, it allocates a pointer that will store a string. But when p9pdu_readf() fails while handling "d" then this pointer will not be freed in p9_check_errors(). Fixes: 51a87c552dfd ("9p: rework client code to use new protocol support functions") Reviewed-by: Christian Schoenebeck Signed-off-by: Hangyu Hua Message-ID: <20231027030302.11927-1-hbh25y@gmail.com> Signed-off-by: Dominique Martinet

9p: v9fs_listxattr: fix %s null argument warning

2023-10-25T22:05:52+00:00

W=1 warns about null argument to kprintf: In file included from fs/9p/xattr.c:12: In function ‘v9fs_xattr_get’, inlined from ‘v9fs_listxattr’ at fs/9p/xattr.c:142:9: include/net/9p/9p.h:55:2: error: ‘%s’ directive argument is null [-Werror=format-overflow=] 55 | _p9_debug(level, __func__, fmt, ##__VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Use an empty string instead of : - this is ok 9p-wise because p9pdu_vwritef serializes a null string and an empty string the same way (one '0' word for length) - since this degrades the print statements, add new single quotes for xattr's name delimter (Old: "file = (null)", new: "file = ''") Link: https://lore.kernel.org/r/20231008060138.517057-1-suhui@nfschina.com Suggested-by: Su Hui Signed-off-by: Dominique Martinet Acked-by: Christian Schoenebeck Message-ID: <20231025103445.1248103-2-asmadeus@codewreck.org>

9p: remove dead stores (variable set again without being read)

2023-07-20T19:14:50+00:00

The 9p code for some reason used to initialize variables outside of the declaration, e.g. instead of just initializing the variable like this: int retval = 0 We would be doing this: int retval; retval = 0; This is perfectly fine and the compiler will just optimize dead stores anyway, but scan-build seems to think this is a problem and there are many of these warnings making the output of scan-build full of such warnings: fs/9p/vfs_inode.c:916:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores] retval = 0; ^ ~ I have no strong opinion here, but if we want to regularly run scan-build we should fix these just to silence the messages. I've confirmed these all are indeed ok to remove. Reviewed-by: Simon Horman Signed-off-by: Dominique Martinet Signed-off-by: Eric Van Hensbergen

9p: Add additional debug flags and open modes

2023-03-27T02:33:48+00:00

Add some additional debug flags to assist with debugging cache changes. Also add some additional open modes so we can track cache state in fids more directly. Signed-off-by: Eric Van Hensbergen

net/9p: fix bug in client create for .L

2023-02-24T13:42:40+00:00

We are supposed to set fid->mode to reflect the flags that were used to open the file. We were actually setting it to the creation mode which is the default perms of the file not the flags the file was opened with. Signed-off-by: Eric Van Hensbergen Reviewed-by: Dominique Martinet

net/9p: Adjust maximum MSIZE to account for p9 header

2023-02-23T22:39:36+00:00

Add maximum p9 header size to MSIZE to make sure we can have page aligned data. Signed-off-by: Eric Van Hensbergen Reviewed-by: Dominique Martinet