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-rw-r--r--arch/alpha/kernel/binfmt_loader.c8
-rw-r--r--fs/binfmt_em86.c9
-rw-r--r--fs/binfmt_misc.c18
-rw-r--r--fs/binfmt_script.c9
-rw-r--r--fs/exec.c51
-rw-r--r--include/linux/binfmts.h3
6 files changed, 43 insertions, 55 deletions
diff --git a/arch/alpha/kernel/binfmt_loader.c b/arch/alpha/kernel/binfmt_loader.c
index d712ba51d15a..e4be7a543ecf 100644
--- a/arch/alpha/kernel/binfmt_loader.c
+++ b/arch/alpha/kernel/binfmt_loader.c
@@ -19,10 +19,6 @@ static int load_binary(struct linux_binprm *bprm)
if (bprm->loader)
return -ENOEXEC;
- allow_write_access(bprm->file);
- fput(bprm->file);
- bprm->file = NULL;
-
loader = bprm->vma->vm_end - sizeof(void *);
file = open_exec("/sbin/loader");
@@ -33,9 +29,9 @@ static int load_binary(struct linux_binprm *bprm)
/* Remember if the application is TASO. */
bprm->taso = eh->ah.entry < 0x100000000UL;
- bprm->file = file;
+ bprm->interpreter = file;
bprm->loader = loader;
- return search_binary_handler(bprm);
+ return 0;
}
static struct linux_binfmt loader_format = {
diff --git a/fs/binfmt_em86.c b/fs/binfmt_em86.c
index cedde2341ade..995883693cb2 100644
--- a/fs/binfmt_em86.c
+++ b/fs/binfmt_em86.c
@@ -48,10 +48,6 @@ static int load_em86(struct linux_binprm *bprm)
if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
return -ENOENT;
- allow_write_access(bprm->file);
- fput(bprm->file);
- bprm->file = NULL;
-
/* Unlike in the script case, we don't have to do any hairy
* parsing to find our interpreter... it's hardcoded!
*/
@@ -89,9 +85,8 @@ static int load_em86(struct linux_binprm *bprm)
if (IS_ERR(file))
return PTR_ERR(file);
- bprm->file = file;
-
- return search_binary_handler(bprm);
+ bprm->interpreter = file;
+ return 0;
}
static struct linux_binfmt em86_format = {
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index ad2866f28f0c..53968ea07b57 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -159,18 +159,9 @@ static int load_misc_binary(struct linux_binprm *bprm)
goto ret;
}
- if (fmt->flags & MISC_FMT_OPEN_BINARY) {
- /* Pass the open binary to the interpreter */
+ if (fmt->flags & MISC_FMT_OPEN_BINARY)
bprm->have_execfd = 1;
- bprm->executable = bprm->file;
- allow_write_access(bprm->file);
- bprm->file = NULL;
- } else {
- allow_write_access(bprm->file);
- fput(bprm->file);
- bprm->file = NULL;
- }
/* make argv[1] be the path to the binary */
retval = copy_strings_kernel(1, &bprm->interp, bprm);
if (retval < 0)
@@ -199,14 +190,11 @@ static int load_misc_binary(struct linux_binprm *bprm)
if (IS_ERR(interp_file))
goto ret;
- bprm->file = interp_file;
+ bprm->interpreter = interp_file;
if (fmt->flags & MISC_FMT_CREDENTIALS)
bprm->preserve_creds = 1;
- retval = search_binary_handler(bprm);
- if (retval < 0)
- goto ret;
-
+ retval = 0;
ret:
dput(fmt->dentry);
return retval;
diff --git a/fs/binfmt_script.c b/fs/binfmt_script.c
index 85e0ef86eb11..0e8b953d12cf 100644
--- a/fs/binfmt_script.c
+++ b/fs/binfmt_script.c
@@ -93,11 +93,6 @@ static int load_script(struct linux_binprm *bprm)
if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)
return -ENOENT;
- /* Release since we are not mapping a binary into memory. */
- allow_write_access(bprm->file);
- fput(bprm->file);
- bprm->file = NULL;
-
/*
* OK, we've parsed out the interpreter name and
* (optional) argument.
@@ -138,8 +133,8 @@ static int load_script(struct linux_binprm *bprm)
if (IS_ERR(file))
return PTR_ERR(file);
- bprm->file = file;
- return search_binary_handler(bprm);
+ bprm->interpreter = file;
+ return 0;
}
static struct linux_binfmt script_format = {
diff --git a/fs/exec.c b/fs/exec.c
index 117ad8fc012b..c3c879a55d65 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1710,16 +1710,12 @@ EXPORT_SYMBOL(remove_arg_zero);
/*
* cycle the list of binary formats handler, until one recognizes the image
*/
-int search_binary_handler(struct linux_binprm *bprm)
+static int search_binary_handler(struct linux_binprm *bprm)
{
bool need_retry = IS_ENABLED(CONFIG_MODULES);
struct linux_binfmt *fmt;
int retval;
- /* This allows 4 levels of binfmt rewrites before failing hard. */
- if (bprm->recursion_depth > 5)
- return -ELOOP;
-
retval = prepare_binprm(bprm);
if (retval < 0)
return retval;
@@ -1736,14 +1732,11 @@ int search_binary_handler(struct linux_binprm *bprm)
continue;
read_unlock(&binfmt_lock);
- bprm->recursion_depth++;
retval = fmt->load_binary(bprm);
- bprm->recursion_depth--;
read_lock(&binfmt_lock);
put_binfmt(fmt);
- if (bprm->point_of_no_return || !bprm->file ||
- (retval != -ENOEXEC)) {
+ if (bprm->point_of_no_return || (retval != -ENOEXEC)) {
read_unlock(&binfmt_lock);
return retval;
}
@@ -1762,12 +1755,11 @@ int search_binary_handler(struct linux_binprm *bprm)
return retval;
}
-EXPORT_SYMBOL(search_binary_handler);
static int exec_binprm(struct linux_binprm *bprm)
{
pid_t old_pid, old_vpid;
- int ret;
+ int ret, depth;
/* Need to fetch pid before load_binary changes it */
old_pid = current->pid;
@@ -1775,15 +1767,38 @@ static int exec_binprm(struct linux_binprm *bprm)
old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent));
rcu_read_unlock();
- ret = search_binary_handler(bprm);
- if (ret >= 0) {
- audit_bprm(bprm);
- trace_sched_process_exec(current, old_pid, bprm);
- ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
- proc_exec_connector(current);
+ /* This allows 4 levels of binfmt rewrites before failing hard. */
+ for (depth = 0;; depth++) {
+ struct file *exec;
+ if (depth > 5)
+ return -ELOOP;
+
+ ret = search_binary_handler(bprm);
+ if (ret < 0)
+ return ret;
+ if (!bprm->interpreter)
+ break;
+
+ exec = bprm->file;
+ bprm->file = bprm->interpreter;
+ bprm->interpreter = NULL;
+
+ allow_write_access(exec);
+ if (unlikely(bprm->have_execfd)) {
+ if (bprm->executable) {
+ fput(exec);
+ return -ENOEXEC;
+ }
+ bprm->executable = exec;
+ } else
+ fput(exec);
}
- return ret;
+ audit_bprm(bprm);
+ trace_sched_process_exec(current, old_pid, bprm);
+ ptrace_event(PTRACE_EVENT_EXEC, old_vpid);
+ proc_exec_connector(current);
+ return 0;
}
/*
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index 653508b25815..7fc05929c967 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -50,8 +50,8 @@ struct linux_binprm {
#ifdef __alpha__
unsigned int taso:1;
#endif
- unsigned int recursion_depth; /* only for search_binary_handler() */
struct file * executable; /* Executable to pass to the interpreter */
+ struct file * interpreter;
struct file * file;
struct cred *cred; /* new credentials */
int unsafe; /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
@@ -117,7 +117,6 @@ static inline void insert_binfmt(struct linux_binfmt *fmt)
extern void unregister_binfmt(struct linux_binfmt *);
extern int __must_check remove_arg_zero(struct linux_binprm *);
-extern int search_binary_handler(struct linux_binprm *);
extern int begin_new_exec(struct linux_binprm * bprm);
extern void setup_new_exec(struct linux_binprm * bprm);
extern void finalize_exec(struct linux_binprm *bprm);