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| author | Trond Myklebust <trond.myklebust@hammerspace.com> | 2019-02-26 19:19:46 +0300 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2019-03-02 00:20:16 +0300 |
| commit | 108bb4afd351d65826648a47f11fa3104e250d9b (patch) | |
| tree | 5424da4ab5c98f6c7bc56894b49b55cd246033bd | |
| parent | 1a3466aed3a17eed41cd9411f89eb637f58349b0 (diff) | |
| download | linux-108bb4afd351d65826648a47f11fa3104e250d9b.tar.xz | |
NFSv4/flexfiles: Fix invalid deref in FF_LAYOUT_DEVID_NODE()
If the attempt to instantiate the mirror's layout DS pointer failed,
then that pointer may hold a value of type ERR_PTR(), so we need
to check that before we dereference it.
Fixes: 65990d1afbd2d ("pNFS/flexfiles: Fix a deadlock on LAYOUTGET")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
| -rw-r--r-- | fs/nfs/flexfilelayout/flexfilelayout.h | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h index c2626bad466b..8a2d5d630af9 100644 --- a/fs/nfs/flexfilelayout/flexfilelayout.h +++ b/fs/nfs/flexfilelayout/flexfilelayout.h @@ -132,16 +132,6 @@ FF_LAYOUT_LSEG(struct pnfs_layout_segment *lseg) generic_hdr); } -static inline struct nfs4_deviceid_node * -FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx) -{ - if (idx >= FF_LAYOUT_LSEG(lseg)->mirror_array_cnt || - FF_LAYOUT_LSEG(lseg)->mirror_array[idx] == NULL || - FF_LAYOUT_LSEG(lseg)->mirror_array[idx]->mirror_ds == NULL) - return NULL; - return &FF_LAYOUT_LSEG(lseg)->mirror_array[idx]->mirror_ds->id_node; -} - static inline struct nfs4_ff_layout_ds * FF_LAYOUT_MIRROR_DS(struct nfs4_deviceid_node *node) { @@ -151,9 +141,25 @@ FF_LAYOUT_MIRROR_DS(struct nfs4_deviceid_node *node) static inline struct nfs4_ff_layout_mirror * FF_LAYOUT_COMP(struct pnfs_layout_segment *lseg, u32 idx) { - if (idx >= FF_LAYOUT_LSEG(lseg)->mirror_array_cnt) - return NULL; - return FF_LAYOUT_LSEG(lseg)->mirror_array[idx]; + struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg); + + if (idx < fls->mirror_array_cnt) + return fls->mirror_array[idx]; + return NULL; +} + +static inline struct nfs4_deviceid_node * +FF_LAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg, u32 idx) +{ + struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, idx); + + if (mirror != NULL) { + struct nfs4_ff_layout_ds *mirror_ds = mirror->mirror_ds; + + if (!IS_ERR_OR_NULL(mirror_ds)) + return &mirror_ds->id_node; + } + return NULL; } static inline u32 |