From 60ef60c7d7291d7cdc43661363cd05a5102e69f6 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 3 Mar 2020 11:43:55 -0500 Subject: __nd_alloc_stack(): make it return bool ... and adjust the caller (reserve_stack()). Rename to nd_alloc_stack(), while we are at it. Signed-off-by: Al Viro --- fs/namei.c | 45 ++++++++++++++++++--------------------------- 1 file changed, 18 insertions(+), 27 deletions(-) (limited to 'fs/namei.c') diff --git a/fs/namei.c b/fs/namei.c index 0539a26dd9b4..7a95a3fcbf68 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -529,24 +529,17 @@ static void restore_nameidata(void) kfree(now->stack); } -static int __nd_alloc_stack(struct nameidata *nd) +static bool nd_alloc_stack(struct nameidata *nd) { struct saved *p; - if (nd->flags & LOOKUP_RCU) { - p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved), - GFP_ATOMIC); - if (unlikely(!p)) - return -ECHILD; - } else { - p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved), - GFP_KERNEL); - if (unlikely(!p)) - return -ENOMEM; - } + p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved), + nd->flags & LOOKUP_RCU ? GFP_ATOMIC : GFP_KERNEL); + if (unlikely(!p)) + return false; memcpy(p, nd->internal, sizeof(nd->internal)); nd->stack = p; - return 0; + return true; } /** @@ -1573,8 +1566,6 @@ static inline int may_lookup(struct nameidata *nd) static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq) { - int error; - if (unlikely(nd->total_link_count++ >= MAXSYMLINKS)) return -ELOOP; @@ -1582,21 +1573,21 @@ static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq) return 0; if (likely(nd->stack != nd->internal)) return 0; - - error = __nd_alloc_stack(nd); - if (likely(!error)) + if (likely(nd_alloc_stack(nd))) return 0; - if (error == -ECHILD) { - // we must grab link first + + if (nd->flags & LOOKUP_RCU) { + // we need to grab link before we do unlazy. And we can't skip + // unlazy even if we fail to grab the link - cleanup needs it bool grabbed_link = legitimize_path(nd, link, seq); - // ... and we must unlazy to be able to clean up - error = unlazy_walk(nd); - if (unlikely(!grabbed_link)) - error = -ECHILD; - if (!error) - error = __nd_alloc_stack(nd); + + if (unlazy_walk(nd) != 0 || !grabbed_link) + return -ECHILD; + + if (nd_alloc_stack(nd)) + return 0; } - return error; + return -ENOMEM; } enum {WALK_TRAILING = 1, WALK_MORE = 2, WALK_NOFOLLOW = 4}; -- cgit