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| author | Elena Reshetova <elena.reshetova@intel.com> | 2017-10-20 12:53:32 +0300 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2017-11-17 13:47:59 -0500 |
| commit | eba6dd691743a9d7a57735f36bf6946fc58878ec (patch) | |
| tree | e6b14b8b629462d1e7707bd32536292e91bccef0 | |
| parent | a2a5dea7b6cb77365ed9c987f54d160668c8a95f (diff) | |
| download | linux-eba6dd691743a9d7a57735f36bf6946fc58878ec.tar.gz linux-eba6dd691743a9d7a57735f36bf6946fc58878ec.tar.bz2 linux-eba6dd691743a9d7a57735f36bf6946fc58878ec.zip | |
fs, nfs: convert pnfs_layout_segment.pls_refcount from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| -rw-r--r-- | fs/nfs/pnfs.c | 12 | ||||
| -rw-r--r-- | fs/nfs/pnfs.h | 4 |
2 files changed, 8 insertions, 8 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 3bcd669a3152..499bb710713e 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -450,7 +450,7 @@ pnfs_init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg, { INIT_LIST_HEAD(&lseg->pls_list); INIT_LIST_HEAD(&lseg->pls_lc_list); - atomic_set(&lseg->pls_refcount, 1); + refcount_set(&lseg->pls_refcount, 1); set_bit(NFS_LSEG_VALID, &lseg->pls_flags); lseg->pls_layout = lo; lseg->pls_range = *range; @@ -507,13 +507,13 @@ pnfs_put_lseg(struct pnfs_layout_segment *lseg) return; dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg, - atomic_read(&lseg->pls_refcount), + refcount_read(&lseg->pls_refcount), test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); lo = lseg->pls_layout; inode = lo->plh_inode; - if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) { + if (refcount_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) { if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags)) { spin_unlock(&inode->i_lock); return; @@ -551,7 +551,7 @@ pnfs_lseg_range_contained(const struct pnfs_layout_range *l1, static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg, struct list_head *tmp_list) { - if (!atomic_dec_and_test(&lseg->pls_refcount)) + if (!refcount_dec_and_test(&lseg->pls_refcount)) return false; pnfs_layout_remove_lseg(lseg->pls_layout, lseg); list_add(&lseg->pls_list, tmp_list); @@ -570,7 +570,7 @@ static int mark_lseg_invalid(struct pnfs_layout_segment *lseg, * outstanding io is finished. */ dprintk("%s: lseg %p ref %d\n", __func__, lseg, - atomic_read(&lseg->pls_refcount)); + refcount_read(&lseg->pls_refcount)); if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list)) rv = 1; } @@ -1546,7 +1546,7 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, } dprintk("%s:Return lseg %p ref %d\n", - __func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0); + __func__, ret, ret ? refcount_read(&ret->pls_refcount) : 0); return ret; } diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index cefa7daf6e85..f0e98e1f04b2 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -64,7 +64,7 @@ struct pnfs_layout_segment { struct list_head pls_list; struct list_head pls_lc_list; struct pnfs_layout_range pls_range; - atomic_t pls_refcount; + refcount_t pls_refcount; u32 pls_seq; unsigned long pls_flags; struct pnfs_layout_hdr *pls_layout; @@ -394,7 +394,7 @@ static inline struct pnfs_layout_segment * pnfs_get_lseg(struct pnfs_layout_segment *lseg) { if (lseg) { - atomic_inc(&lseg->pls_refcount); + refcount_inc(&lseg->pls_refcount); smp_mb__after_atomic(); } return lseg; |