[PATCH v5 01/15] binfmt_flat: assorted cleanups

From: Nicolas Pitre
Date: Sun Jul 24 2016 - 11:31:32 EST

Remove excessive casts, do some code grouping, fix most important
checkpatch.pl complaints, etc.

No functional changes.

Signed-off-by: Nicolas Pitre <nico@xxxxxxxxxx>
Reviewed-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
---
fs/binfmt_flat.c | 230 ++++++++++++++++++++++++++-----------------------------
1 file changed, 109 insertions(+), 121 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index caf9e39bb8..892dba62bf 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -15,7 +15,6 @@
* JAN/99 -- coded full program relocation (gerg@xxxxxxxxxxxx)
*/

-#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
@@ -25,8 +24,6 @@
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/file.h>
-#include <linux/stat.h>
-#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/slab.h>
@@ -34,10 +31,9 @@
#include <linux/personality.h>
#include <linux/init.h>
#include <linux/flat.h>
-#include <linux/syscalls.h>
+#include <linux/uaccess.h>

#include <asm/byteorder.h>
-#include <asm/uaccess.h>
#include <asm/unaligned.h>
#include <asm/cacheflush.h>
#include <asm/page.h>
@@ -80,7 +76,7 @@ struct lib_info {
unsigned long text_len; /* Length of text segment */
unsigned long entry; /* Start address for this module */
unsigned long build_date; /* When this one was compiled */
- short loaded; /* Has this library been loaded? */
+ bool loaded; /* Has this library been loaded? */
} lib_list[MAX_SHARED_LIBS];
};

@@ -107,8 +103,8 @@ static struct linux_binfmt flat_format = {
static int flat_core_dump(struct coredump_params *cprm)
{
printk("Process %s:%d received signr %d and should have core dumped\n",
- current->comm, current->pid, (int) cprm->siginfo->si_signo);
- return(1);
+ current->comm, current->pid, cprm->siginfo->si_signo);
+ return 1;
}

/****************************************************************************/
@@ -120,11 +116,11 @@ static int flat_core_dump(struct coredump_params *cprm)

static unsigned long create_flat_tables(
unsigned long pp,
- struct linux_binprm * bprm)
+ struct linux_binprm *bprm)
{
- unsigned long *argv,*envp;
- unsigned long * sp;
- char * p = (char*)pp;
+ unsigned long *argv, *envp;
+ unsigned long *sp;
+ char *p = (char *)pp;
int argc = bprm->argc;
int envc = bprm->envc;
char uninitialized_var(dummy);
@@ -142,7 +138,7 @@ static unsigned long create_flat_tables(

put_user(argc, sp);
current->mm->arg_start = (unsigned long) p;
- while (argc-->0) {
+ while (argc-- > 0) {
put_user((unsigned long) p, argv++);
do {
get_user(dummy, p); p++;
@@ -150,7 +146,7 @@ static unsigned long create_flat_tables(
}
put_user((unsigned long) NULL, argv);
current->mm->arg_end = current->mm->env_start = (unsigned long) p;
- while (envc-->0) {
+ while (envc-- > 0) {
put_user((unsigned long)p, envp); envp++;
do {
get_user(dummy, p); p++;
@@ -190,7 +186,7 @@ static int decompress_exec(
loff_t fpos;
int ret, retval;

- DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
+ DBG_FLT("decompress_exec(offset=%lx,buf=%p,len=%lx)\n", offset, dst, len);

memset(&strm, 0, sizeof(strm));
strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
@@ -243,7 +239,7 @@ static int decompress_exec(
ret = 10;
if (buf[3] & EXTRA_FIELD) {
ret += 2 + buf[10] + (buf[11] << 8);
- if (unlikely(LBUFSIZE <= ret)) {
+ if (unlikely(ret >= LBUFSIZE)) {
DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
goto out_free_buf;
}
@@ -251,7 +247,7 @@ static int decompress_exec(
if (buf[3] & ORIG_NAME) {
while (ret < LBUFSIZE && buf[ret++] != 0)
;
- if (unlikely(LBUFSIZE == ret)) {
+ if (unlikely(ret == LBUFSIZE)) {
DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
goto out_free_buf;
}
@@ -259,7 +255,7 @@ static int decompress_exec(
if (buf[3] & COMMENT) {
while (ret < LBUFSIZE && buf[ret++] != 0)
;
- if (unlikely(LBUFSIZE == ret)) {
+ if (unlikely(ret == LBUFSIZE)) {
DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
goto out_free_buf;
}
@@ -327,17 +323,17 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
r &= 0x00ffffff; /* Trim ID off here */
}
if (id >= MAX_SHARED_LIBS) {
- printk("BINFMT_FLAT: reference 0x%x to shared library %d",
- (unsigned) r, id);
+ printk("BINFMT_FLAT: reference 0x%lx to shared library %d",
+ r, id);
goto failed;
}
if (curid != id) {
if (internalp) {
- printk("BINFMT_FLAT: reloc address 0x%x not in same module "
- "(%d != %d)", (unsigned) r, curid, id);
+ printk("BINFMT_FLAT: reloc address 0x%lx not in same module "
+ "(%d != %d)", r, curid, id);
goto failed;
- } else if ( ! p->lib_list[id].loaded &&
- load_flat_shared_library(id, p) < 0) {
+ } else if (!p->lib_list[id].loaded &&
+ load_flat_shared_library(id, p) < 0) {
printk("BINFMT_FLAT: failed to load library %d", id);
goto failed;
}
@@ -358,8 +354,8 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
text_len = p->lib_list[id].text_len;

if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
- printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
- (int) r,(int)(start_brk-start_data+text_len),(int)text_len);
+ printk("BINFMT_FLAT: reloc outside program 0x%lx (0 - 0x%lx/0x%lx)",
+ r, start_brk-start_data+text_len, text_len);
goto failed;
}

@@ -369,7 +365,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
addr = r - text_len + start_data;

/* Range checked already above so doing the range tests is redundant...*/
- return(addr);
+ return addr;

failed:
printk(", killing %s!\n", current->comm);
@@ -383,11 +379,11 @@ failed:
static void old_reloc(unsigned long rl)
{
#ifdef DEBUG
- char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
+ static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
#endif
flat_v2_reloc_t r;
unsigned long *ptr;
-
+
r.value = rl;
#if defined(CONFIG_COLDFIRE)
ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
@@ -397,10 +393,10 @@ static void old_reloc(unsigned long rl)

#ifdef DEBUG
printk("Relocation of variable at DATASEG+%x "
- "(address %p, currently %x) into segment %s\n",
- r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
+ "(address %p, currently %lx) into segment %s\n",
+ r.reloc.offset, ptr, *ptr, segment[r.reloc.type]);
#endif
-
+
switch (r.reloc.type) {
case OLD_FLAT_RELOC_TYPE_TEXT:
*ptr += current->mm->start_code;
@@ -417,27 +413,25 @@ static void old_reloc(unsigned long rl)
}

#ifdef DEBUG
- printk("Relocation became %x\n", (int)*ptr);
+ printk("Relocation became %lx\n", *ptr);
#endif
-}
+}

/****************************************************************************/

-static int load_flat_file(struct linux_binprm * bprm,
+static int load_flat_file(struct linux_binprm *bprm,
struct lib_info *libinfo, int id, unsigned long *extra_stack)
{
- struct flat_hdr * hdr;
- unsigned long textpos = 0, datapos = 0, result;
- unsigned long realdatastart = 0;
- unsigned long text_len, data_len, bss_len, stack_len, flags;
- unsigned long full_data;
- unsigned long len, memp = 0;
- unsigned long memp_size, extra, rlim;
- unsigned long *reloc = 0, *rp;
+ struct flat_hdr *hdr;
+ unsigned long textpos, datapos, realdatastart;
+ unsigned long text_len, data_len, bss_len, stack_len, full_data, flags;
+ unsigned long len, memp, memp_size, extra, rlim;
+ unsigned long *reloc, *rp;
struct inode *inode;
- int i, rev, relocs = 0;
+ int i, rev, relocs;
loff_t fpos;
unsigned long start_code, end_code;
+ ssize_t result;
int ret;

hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
@@ -478,11 +472,11 @@ static int load_flat_file(struct linux_binprm * bprm,
ret = -ENOEXEC;
goto err;
}
-
+
/* Don't allow old format executables to use shared libraries */
if (rev == OLD_FLAT_VERSION && id != 0) {
- printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
- (int) FLAT_VERSION);
+ printk("BINFMT_FLAT: shared libraries are not available before rev 0x%lx\n",
+ FLAT_VERSION);
ret = -ENOEXEC;
goto err;
}
@@ -517,11 +511,9 @@ static int load_flat_file(struct linux_binprm * bprm,

/* Flush all traces of the currently running executable */
if (id == 0) {
- result = flush_old_exec(bprm);
- if (result) {
- ret = result;
+ ret = flush_old_exec(bprm);
+ if (ret)
goto err;
- }

/* OK, This is the point of no return */
set_personality(PER_LINUX_32BIT);
@@ -549,38 +541,38 @@ static int load_flat_file(struct linux_binprm * bprm,
textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
MAP_PRIVATE|MAP_EXECUTABLE, 0);
if (!textpos || IS_ERR_VALUE(textpos)) {
- if (!textpos)
- textpos = (unsigned long) -ENOMEM;
- printk("Unable to mmap process text, errno %d\n", (int)-textpos);
ret = textpos;
+ if (!textpos)
+ ret = -ENOMEM;
+ printk("Unable to mmap process text, errno %d\n", ret);
goto err;
}

len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
len = PAGE_ALIGN(len);
- realdatastart = vm_mmap(0, 0, len,
+ realdatastart = vm_mmap(NULL, 0, len,
PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);

if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
+ ret = realdatastart;
if (!realdatastart)
- realdatastart = (unsigned long) -ENOMEM;
- printk("Unable to allocate RAM for process data, errno %d\n",
- (int)-realdatastart);
+ ret = -ENOMEM;
+ printk("Unable to allocate RAM for process data, "
+ "errno %d\n", ret);
vm_munmap(textpos, text_len);
- ret = realdatastart;
goto err;
}
datapos = ALIGN(realdatastart +
MAX_SHARED_LIBS * sizeof(unsigned long),
FLAT_DATA_ALIGN);

- DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
- (int)(data_len + bss_len + stack_len), (int)datapos);
+ DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%ld bytes): %lx\n",
+ data_len + bss_len + stack_len, datapos);

fpos = ntohl(hdr->data_start);
#ifdef CONFIG_BINFMT_ZFLAT
if (flags & FLAT_FLAG_GZDATA) {
- result = decompress_exec(bprm, fpos, (char *) datapos,
+ result = decompress_exec(bprm, fpos, (char *)datapos,
full_data, 0);
} else
#endif
@@ -589,29 +581,30 @@ static int load_flat_file(struct linux_binprm * bprm,
full_data);
}
if (IS_ERR_VALUE(result)) {
- printk("Unable to read data+bss, errno %d\n", (int)-result);
+ ret = result;
+ printk("Unable to read data+bss, errno %d\n", ret);
vm_munmap(textpos, text_len);
vm_munmap(realdatastart, len);
- ret = result;
goto err;
}

- reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
+ reloc = (unsigned long *)
+ (datapos + (ntohl(hdr->reloc_start) - text_len));
memp = realdatastart;
memp_size = len;
} else {

len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
len = PAGE_ALIGN(len);
- textpos = vm_mmap(0, 0, len,
+ textpos = vm_mmap(NULL, 0, len,
PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);

if (!textpos || IS_ERR_VALUE(textpos)) {
- if (!textpos)
- textpos = (unsigned long) -ENOMEM;
- printk("Unable to allocate RAM for process text/data, errno %d\n",
- (int)-textpos);
ret = textpos;
+ if (!textpos)
+ ret = -ENOMEM;
+ printk("Unable to allocate RAM for process text/data, "
+ "errno %d\n", ret);
goto err;
}

@@ -629,10 +622,10 @@ static int load_flat_file(struct linux_binprm * bprm,
* load it all in and treat it like a RAM load from now on
*/
if (flags & FLAT_FLAG_GZIP) {
- result = decompress_exec(bprm, sizeof (struct flat_hdr),
- (((char *) textpos) + sizeof (struct flat_hdr)),
+ result = decompress_exec(bprm, sizeof(struct flat_hdr),
+ (((char *)textpos) + sizeof(struct flat_hdr)),
(text_len + full_data
- - sizeof (struct flat_hdr)),
+ - sizeof(struct flat_hdr)),
0);
memmove((void *) datapos, (void *) realdatastart,
full_data);
@@ -641,8 +634,7 @@ static int load_flat_file(struct linux_binprm * bprm,
if (!IS_ERR_VALUE(result))
result = decompress_exec(bprm, text_len, (char *) datapos,
full_data, 0);
- }
- else
+ } else
#endif
{
result = read_code(bprm->file, textpos, 0, text_len);
@@ -652,21 +644,19 @@ static int load_flat_file(struct linux_binprm * bprm,
full_data);
}
if (IS_ERR_VALUE(result)) {
- printk("Unable to read code+data+bss, errno %d\n",(int)-result);
+ ret = result;
+ printk("Unable to read code+data+bss, errno %d\n", ret);
vm_munmap(textpos, text_len + data_len + extra +
MAX_SHARED_LIBS * sizeof(unsigned long));
- ret = result;
goto err;
}
}

- if (flags & FLAT_FLAG_KTRACE)
- printk("Mapping is %x, Entry point is %x, data_start is %x\n",
- (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
+ start_code = textpos + sizeof(struct flat_hdr);
+ end_code = textpos + text_len;
+ text_len -= sizeof(struct flat_hdr); /* the real code len */

/* The main program needs a little extra setup in the task structure */
- start_code = textpos + sizeof (struct flat_hdr);
- end_code = textpos + text_len;
if (id == 0) {
current->mm->start_code = start_code;
current->mm->end_code = end_code;
@@ -684,16 +674,14 @@ static int load_flat_file(struct linux_binprm * bprm,
current->mm->context.end_brk = memp + memp_size - stack_len;
}

- if (flags & FLAT_FLAG_KTRACE)
- printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
- id ? "Lib" : "Load", bprm->filename,
- (int) start_code, (int) end_code,
- (int) datapos,
- (int) (datapos + data_len),
- (int) (datapos + data_len),
- (int) (((datapos + data_len + bss_len) + 3) & ~3));
-
- text_len -= sizeof(struct flat_hdr); /* the real code len */
+ if (flags & FLAT_FLAG_KTRACE) {
+ printk("Mapping is %lx, Entry point is %x, data_start is %x\n",
+ textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
+ printk("%s %s: TEXT=%lx-%lx DATA=%lx-%lx BSS=%lx-%lx\n",
+ id ? "Lib" : "Load", bprm->filename,
+ start_code, end_code, datapos, datapos + data_len,
+ datapos + data_len, (datapos + data_len + bss_len + 3) & ~3);
+ }

/* Store the current module values into the global library structure */
libinfo->lib_list[id].start_code = start_code;
@@ -703,7 +691,7 @@ static int load_flat_file(struct linux_binprm * bprm,
libinfo->lib_list[id].loaded = 1;
libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
-
+
/*
* We just load the allocations into some temporary memory to
* help simplify all this mumbo jumbo
@@ -743,14 +731,16 @@ static int load_flat_file(struct linux_binprm * bprm,
*/
if (rev > OLD_FLAT_VERSION) {
unsigned long persistent = 0;
- for (i=0; i < relocs; i++) {
+ for (i = 0; i < relocs; i++) {
unsigned long addr, relval;

- /* Get the address of the pointer to be
- relocated (of course, the address has to be
- relocated first). */
+ /*
+ * Get the address of the pointer to be
+ * relocated (of course, the address has to be
+ * relocated first).
+ */
relval = ntohl(reloc[i]);
- if (flat_set_persistent (relval, &persistent))
+ if (flat_set_persistent(relval, &persistent))
continue;
addr = flat_get_relocate_addr(relval);
rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
@@ -780,14 +770,14 @@ static int load_flat_file(struct linux_binprm * bprm,
}
}
} else {
- for (i=0; i < relocs; i++)
+ for (i = 0; i < relocs; i++)
old_reloc(ntohl(reloc[i]));
}
-
+
flush_icache_range(start_code, end_code);

/* zero the BSS, BRK and stack areas */
- memset((void*)(datapos + data_len), 0, bss_len +
+ memset((void *)(datapos + data_len), 0, bss_len +
(memp + memp_size - stack_len - /* end brk */
libinfo->lib_list[id].start_brk) + /* start brk */
stack_len);
@@ -846,7 +836,7 @@ out:
allow_write_access(bprm.file);
fput(bprm.file);

- return(res);
+ return res;
}

#endif /* CONFIG_BINFMT_SHARED_FLAT */
@@ -857,7 +847,7 @@ out:
* libraries. There is no binary dependent code anywhere else.
*/

-static int load_flat_binary(struct linux_binprm * bprm)
+static int load_flat_binary(struct linux_binprm *bprm)
{
struct lib_info libinfo;
struct pt_regs *regs = current_pt_regs();
@@ -869,6 +859,7 @@ static int load_flat_binary(struct linux_binprm * bprm)
int i, j;

memset(&libinfo, 0, sizeof(libinfo));
+
/*
* We have to add the size of our arguments to our stack size
* otherwise it's too easy for users to create stack overflows
@@ -881,33 +872,33 @@ static int load_flat_binary(struct linux_binprm * bprm)
stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
stack_len += FLAT_STACK_ALIGN - 1; /* reserve for upcoming alignment */
-
+
res = load_flat_file(bprm, &libinfo, 0, &stack_len);
if (res < 0)
return res;
-
+
/* Update data segment pointers for all libraries */
- for (i=0; i<MAX_SHARED_LIBS; i++)
+ for (i = 0; i < MAX_SHARED_LIBS; i++)
if (libinfo.lib_list[i].loaded)
- for (j=0; j<MAX_SHARED_LIBS; j++)
+ for (j = 0; j < MAX_SHARED_LIBS; j++)
(-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
- (libinfo.lib_list[j].loaded)?
- libinfo.lib_list[j].start_data:UNLOADED_LIB;
+ (libinfo.lib_list[j].loaded) ?
+ libinfo.lib_list[j].start_data : UNLOADED_LIB;

install_exec_creds(bprm);

set_binfmt(&flat_format);

p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
- DBG_FLT("p=%x\n", (int)p);
+ DBG_FLT("p=%lx\n", p);

/* copy the arg pages onto the stack, this could be more efficient :-) */
for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
- * (char *) --p =
+ *(char *) --p =
((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];

sp = (unsigned long *) create_flat_tables(p, bprm);
-
+
/* Fake some return addresses to ensure the call chain will
* initialise library in order for us. We are required to call
* lib 1 first, then 2, ... and finally the main program (id 0).
@@ -915,7 +906,7 @@ static int load_flat_binary(struct linux_binprm * bprm)
start_addr = libinfo.lib_list[0].entry;

#ifdef CONFIG_BINFMT_SHARED_FLAT
- for (i = MAX_SHARED_LIBS-1; i>0; i--) {
+ for (i = MAX_SHARED_LIBS-1; i > 0; i--) {
if (libinfo.lib_list[i].loaded) {
/* Push previos first to call address */
--sp; put_user(start_addr, sp);
@@ -923,16 +914,16 @@ static int load_flat_binary(struct linux_binprm * bprm)
}
}
#endif
-
+
/* Stash our initial stack pointer into the mm structure */
- current->mm->start_stack = (unsigned long )sp;
+ current->mm->start_stack = (unsigned long)sp;

#ifdef FLAT_PLAT_INIT
FLAT_PLAT_INIT(regs);
#endif
- DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
- (int)regs, (int)start_addr, (int)current->mm->start_stack);
-
+
+ DBG_FLT("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n",
+ regs, start_addr, current->mm->start_stack);
start_thread(regs, start_addr, current->mm->start_stack);

return 0;
@@ -945,9 +936,6 @@ static int __init init_flat_binfmt(void)
register_binfmt(&flat_format);
return 0;
}
-
-/****************************************************************************/
-
core_initcall(init_flat_binfmt);

/****************************************************************************/
--
2.7.4