kernel/linux.git/net/sunrpc/sysfs.c, branch v5.15.211

SUNRPC: Do not dereference non-socket transports in sysfs

2026-06-01T15:35:44+00:00

[ Upstream commit 421ab1be43bd015ffe744f4ea25df4f19d1ce6fe ] Do not cast the struct xprt to a sock_xprt unless we know it is a UDP or TCP transport. Otherwise the call to lock the mutex will scribble over whatever structure is actually there. This has been seen to cause hard system lockups when the underlying transport was RDMA. Fixes: b49ea673e119 ("SUNRPC: lock against ->sock changing during sysfs read") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

SUNRPC: Check if the xprt is connected before handling sysfs reads

2026-06-01T15:35:44+00:00

[ Upstream commit 17f09d3f619a7ad2d2b021b4e5246f08225b1b0f ] xprts don't immediately reconnect when changing the "dstaddr" property, instead this gets handled the next time an operation uses the transport. This could lead to NULL pointer dereferences when trying to read sysfs files between the disconnect and reconnect operations. Fix this by returning an error if the xprt is not connected. Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust Stable-dep-of: 421ab1be43bd ("SUNRPC: Do not dereference non-socket transports in sysfs") Signed-off-by: Sasha Levin

SUNRPC: lock against ->sock changing during sysfs read

2026-06-01T15:35:11+00:00

[ Upstream commit b49ea673e119f59c71645e2f65b3ccad857c90ee ] ->sock can be set to NULL asynchronously unless ->recv_mutex is held. So it is important to hold that mutex. Otherwise a sysfs read can trigger an oops. Commit 17f09d3f619a ("SUNRPC: Check if the xprt is connected before handling sysfs reads") appears to attempt to fix this problem, but it only narrows the race window. Fixes: 17f09d3f619a ("SUNRPC: Check if the xprt is connected before handling sysfs reads") Fixes: a8482488a7d6 ("SUNRPC query transport's source port") Signed-off-by: NeilBrown Signed-off-by: Anna Schumaker Signed-off-by: Robert Garcia Signed-off-by: Greg Kroah-Hartman

SUNRPC: Fix null-ptr-deref when xps sysfs alloc failed

2022-11-10T17:15:26+00:00

[ Upstream commit cbdeaee94a415800c65a8c3fa04d9664a8b8fb3a ] There is a null-ptr-deref when xps sysfs alloc failed: BUG: KASAN: null-ptr-deref in sysfs_do_create_link_sd+0x40/0xd0 Read of size 8 at addr 0000000000000030 by task gssproxy/457 CPU: 5 PID: 457 Comm: gssproxy Not tainted 6.0.0-09040-g02357b27ee03 #9 Call Trace: dump_stack_lvl+0x34/0x44 kasan_report+0xa3/0x120 sysfs_do_create_link_sd+0x40/0xd0 rpc_sysfs_client_setup+0x161/0x1b0 rpc_new_client+0x3fc/0x6e0 rpc_create_xprt+0x71/0x220 rpc_create+0x1d4/0x350 gssp_rpc_create+0xc3/0x160 set_gssp_clnt+0xbc/0x140 write_gssp+0x116/0x1a0 proc_reg_write+0xd6/0x130 vfs_write+0x177/0x690 ksys_write+0xb9/0x150 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 When the xprt_switch sysfs alloc failed, should not add xprt and switch sysfs to it, otherwise, maybe null-ptr-deref; also initialize the 'xps_sysfs' to NULL to avoid oops when destroy it. Fixes: 2a338a543163 ("sunrpc: add a symlink from rpc-client directory to the xprt_switch") Fixes: d408ebe04ac5 ("sunrpc: add add sysfs directory per xprt under each xprt_switch") Fixes: baea99445dd4 ("sunrpc: add xprt_switch direcotry to sunrpc's sysfs") Signed-off-by: Zhang Xiaoxu Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

net/sunrpc: fix potential memory leaks in rpc_sysfs_xprt_state_change()

2022-08-25T09:40:23+00:00

commit bfc48f1b0505ffcb03a6d749139b7577d6b81ae0 upstream. The issue happens on some error handling paths. When the function fails to grab the object `xprt`, it simply returns 0, forgetting to decrease the reference count of another object `xps`, which is increased by rpc_sysfs_xprt_kobj_get_xprt_switch(), causing refcount leaks. Also, the function forgets to check whether `xps` is valid before using it, which may result in NULL-dereferencing issues. Fix it by adding proper error handling code when either `xprt` or `xps` is NULL. Fixes: 5b7eb78486cd ("SUNRPC: take a xprt offline using sysfs") Signed-off-by: Xin Xiong Signed-off-by: Xin Tan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sunrpc: Fix potential race conditions in rpc_sysfs_xprt_state_change()

2022-02-16T11:56:10+00:00

[ Upstream commit 1a48db3fef499f615b56093947ec4b0d3d8e3021 ] We need to use test_and_set_bit() when changing xprt state flags to avoid potentially getting xps->xps_nactive out of sync. Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

net/sunrpc: fix reference count leaks in rpc_sysfs_xprt_state_change

2022-02-16T11:56:10+00:00

[ Upstream commit 776d794f28c95051bc70405a7b1fa40115658a18 ] The refcount leak issues take place in an error handling path. When the 3rd argument buf doesn't match with "offline", "online" or "remove", the function simply returns -EINVAL and forgets to decrease the reference count of a rpc_xprt object and a rpc_xprt_switch object increased by rpc_sysfs_xprt_kobj_get_xprt() and rpc_sysfs_xprt_kobj_get_xprt_switch(), causing reference count leaks of both unused objects. Fix this issue by jumping to the error handling path labelled with out_put when buf matches none of "offline", "online" or "remove". Signed-off-by: Xiyu Yang Signed-off-by: Xin Xiong Signed-off-by: Xin Tan Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

SUNRPC add xps_nunique_destaddr_xprts to xprt_switch_info in sysfs

2021-08-27T20:37:03+00:00

In sysfs's xprt_switch_info attribute also display the value of number of transports with unique destination addresses for this xprt_switch. Signed-off-by: Olga Kornievskaia Signed-off-by: Anna Schumaker

SUNRPC: Add dst_port to the sysfs xprt info file

2021-08-09T21:25:51+00:00

This is most likely going to be 2049 for NFS, but some servers might be configured to export on a non-standard port. Let's show this information just in case somebody needs it. Signed-off-by: Anna Schumaker

SUNRPC: Add srcaddr as a file in sysfs

2021-08-09T21:25:44+00:00

I don't support changing it right now, but it could be useful information for clients with multiple network cards. Signed-off-by: Anna Schumaker