From 2b358b4ea5b2912726d872611089e790a8388b62 Mon Sep 17 00:00:00 2001 From: Frank Zago Date: Fri, 15 Aug 2014 12:48:12 -0400 Subject: [PATCH] staging/lustre/llite: optimize ll_fid2path() The only parameter from userspace that matters is the length of the buffer. We don't need to allocate then import the whole structure. By importing only that length, we can save a memory allocation. Add sparse annotations to that function. Signed-off-by: frank zago Reviewed-on: http://review.whamcloud.com/11167 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5389 Reviewed-by: John L. Hammond Reviewed-by: Andreas Dilger Signed-off-by: Oleg Drokin Signed-off-by: Greg Kroah-Hartman --- drivers/staging/lustre/lustre/llite/file.c | 34 +++++++++---------- .../lustre/lustre/llite/llite_internal.h | 2 +- 2 files changed, 17 insertions(+), 19 deletions(-) diff --git a/drivers/staging/lustre/lustre/llite/file.c b/drivers/staging/lustre/lustre/llite/file.c index 084fb9206fd5..d3874e1afba8 100644 --- a/drivers/staging/lustre/lustre/llite/file.c +++ b/drivers/staging/lustre/lustre/llite/file.c @@ -1702,37 +1702,35 @@ out: return rc; } -int ll_fid2path(struct inode *inode, void *arg) +int ll_fid2path(struct inode *inode, void __user *arg) { - struct obd_export *exp = ll_i2mdexp(inode); - struct getinfo_fid2path *gfout, *gfin; - int outsize, rc; + struct obd_export *exp = ll_i2mdexp(inode); + const struct getinfo_fid2path __user *gfin = arg; + struct getinfo_fid2path *gfout; + u32 pathlen; + size_t outsize; + int rc; if (!capable(CFS_CAP_DAC_READ_SEARCH) && !(ll_i2sbi(inode)->ll_flags & LL_SBI_USER_FID2PATH)) return -EPERM; - /* Need to get the buflen */ - OBD_ALLOC_PTR(gfin); - if (gfin == NULL) - return -ENOMEM; - if (copy_from_user(gfin, arg, sizeof(*gfin))) { - OBD_FREE_PTR(gfin); + /* Only need to get the buflen */ + if (get_user(pathlen, &gfin->gf_pathlen)) return -EFAULT; - } - outsize = sizeof(*gfout) + gfin->gf_pathlen; + outsize = sizeof(*gfout) + pathlen; + OBD_ALLOC(gfout, outsize); - if (gfout == NULL) { - OBD_FREE_PTR(gfin); + if (gfout == NULL) return -ENOMEM; - } - memcpy(gfout, gfin, sizeof(*gfout)); - OBD_FREE_PTR(gfin); + + if (copy_from_user(gfout, arg, sizeof(*gfout))) + GOTO(gf_free, rc = -EFAULT); /* Call mdc_iocontrol */ rc = obd_iocontrol(OBD_IOC_FID2PATH, exp, outsize, gfout, NULL); - if (rc) + if (rc != 0) GOTO(gf_free, rc); if (copy_to_user(arg, gfout, outsize)) diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h index 684405e26b58..b42d87971f5e 100644 --- a/drivers/staging/lustre/lustre/llite/llite_internal.h +++ b/drivers/staging/lustre/lustre/llite/llite_internal.h @@ -775,7 +775,7 @@ int ll_dir_getstripe(struct inode *inode, struct lov_mds_md **lmmp, int *lmm_size, struct ptlrpc_request **request); int ll_fsync(struct file *file, loff_t start, loff_t end, int data); int ll_merge_lvb(const struct lu_env *env, struct inode *inode); -int ll_fid2path(struct inode *inode, void *arg); +int ll_fid2path(struct inode *inode, void __user *arg); int ll_data_version(struct inode *inode, __u64 *data_version, int extent_lock); int ll_hsm_release(struct inode *inode); -- 2.39.5