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-rw-r--r--kernel/futex.c41
-rw-r--r--kernel/module.c27
2 files changed, 38 insertions, 30 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index 3717e7b306e0..20ef219bbe9b 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -716,7 +716,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
struct futex_pi_state **ps,
struct task_struct *task, int set_waiters)
{
- int lock_taken, ret, ownerdied = 0;
+ int lock_taken, ret, force_take = 0;
u32 uval, newval, curval, vpid = task_pid_vnr(task);
retry:
@@ -755,17 +755,15 @@ retry:
newval = curval | FUTEX_WAITERS;
/*
- * There are two cases, where a futex might have no owner (the
- * owner TID is 0): OWNER_DIED. We take over the futex in this
- * case. We also do an unconditional take over, when the owner
- * of the futex died.
- *
- * This is safe as we are protected by the hash bucket lock !
+ * Should we force take the futex? See below.
*/
- if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) {
- /* Keep the OWNER_DIED bit */
+ if (unlikely(force_take)) {
+ /*
+ * Keep the OWNER_DIED and the WAITERS bit and set the
+ * new TID value.
+ */
newval = (curval & ~FUTEX_TID_MASK) | vpid;
- ownerdied = 0;
+ force_take = 0;
lock_taken = 1;
}
@@ -775,7 +773,7 @@ retry:
goto retry;
/*
- * We took the lock due to owner died take over.
+ * We took the lock due to forced take over.
*/
if (unlikely(lock_taken))
return 1;
@@ -790,20 +788,25 @@ retry:
switch (ret) {
case -ESRCH:
/*
- * No owner found for this futex. Check if the
- * OWNER_DIED bit is set to figure out whether
- * this is a robust futex or not.
+ * We failed to find an owner for this
+ * futex. So we have no pi_state to block
+ * on. This can happen in two cases:
+ *
+ * 1) The owner died
+ * 2) A stale FUTEX_WAITERS bit
+ *
+ * Re-read the futex value.
*/
if (get_futex_value_locked(&curval, uaddr))
return -EFAULT;
/*
- * We simply start over in case of a robust
- * futex. The code above will take the futex
- * and return happy.
+ * If the owner died or we have a stale
+ * WAITERS bit the owner TID in the user space
+ * futex is 0.
*/
- if (curval & FUTEX_OWNER_DIED) {
- ownerdied = 1;
+ if (!(curval & FUTEX_TID_MASK)) {
+ force_take = 1;
goto retry;
}
default:
diff --git a/kernel/module.c b/kernel/module.c
index 6085f5ef88ea..6e48c3a43599 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2293,12 +2293,17 @@ static void layout_symtab(struct module *mod, struct load_info *info)
src = (void *)info->hdr + symsect->sh_offset;
nsrc = symsect->sh_size / sizeof(*src);
+ /* strtab always starts with a nul, so offset 0 is the empty string. */
+ strtab_size = 1;
+
/* Compute total space required for the core symbols' strtab. */
- for (ndst = i = strtab_size = 1; i < nsrc; ++i, ++src)
- if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) {
- strtab_size += strlen(&info->strtab[src->st_name]) + 1;
+ for (ndst = i = 0; i < nsrc; i++) {
+ if (i == 0 ||
+ is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
+ strtab_size += strlen(&info->strtab[src[i].st_name])+1;
ndst++;
}
+ }
/* Append room for core symbols at end of core part. */
info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
@@ -2332,15 +2337,15 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
mod->core_symtab = dst = mod->module_core + info->symoffs;
mod->core_strtab = s = mod->module_core + info->stroffs;
src = mod->symtab;
- *dst = *src;
*s++ = 0;
- for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
- if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
- continue;
-
- dst[ndst] = *src;
- dst[ndst++].st_name = s - mod->core_strtab;
- s += strlcpy(s, &mod->strtab[src->st_name], KSYM_NAME_LEN) + 1;
+ for (ndst = i = 0; i < mod->num_symtab; i++) {
+ if (i == 0 ||
+ is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
+ dst[ndst] = src[i];
+ dst[ndst++].st_name = s - mod->core_strtab;
+ s += strlcpy(s, &mod->strtab[src[i].st_name],
+ KSYM_NAME_LEN) + 1;
+ }
}
mod->core_num_syms = ndst;
}