From 3dc20cb282ec03cc4c997130d680c800011ed479 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 13 Apr 2013 20:31:37 -0400
Subject: [PATCH] new helper: read_code()
switch binfmts that use ->read() to that (and to kernel_read()
in several cases in binfmt_flat - sure, it's nommu, but still,
doing ->read() into kmalloc'ed buffer...)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
arch/x86/ia32/ia32_aout.c | 30 ++++++------------------------
fs/binfmt_aout.c | 25 ++++++-------------------
fs/binfmt_elf_fdpic.c | 7 ++-----
fs/binfmt_flat.c | 37 ++++++++++++++++++-------------------
fs/exec.c | 9 +++++++++
include/linux/binfmts.h | 1 +
6 files changed, 42 insertions(+), 67 deletions(-)
diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c
index 03abf9b70011..03d721cbbc32 100644
--- a/arch/x86/ia32/ia32_aout.c
+++ b/arch/x86/ia32/ia32_aout.c
@@ -323,11 +323,8 @@ static int load_aout_binary(struct linux_binprm *bprm)
if (N_MAGIC(ex) == OMAGIC) {
unsigned long text_addr, map_size;
- loff_t pos;
text_addr = N_TXTADDR(ex);
-
- pos = 32;
map_size = ex.a_text+ex.a_data;
error = vm_brk(text_addr & PAGE_MASK, map_size);
@@ -337,15 +334,12 @@ static int load_aout_binary(struct linux_binprm *bprm)
return error;
}
- error = bprm->file->f_op->read(bprm->file,
- (char __user *)text_addr,
- ex.a_text+ex.a_data, &pos);
+ error = read_code(bprm->file, text_addr, 32,
+ ex.a_text + ex.a_data);
if ((signed long)error < 0) {
send_sig(SIGKILL, current, 0);
return error;
}
-
- flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
} else {
#ifdef WARN_OLD
static unsigned long error_time, error_time2;
@@ -367,15 +361,9 @@ static int load_aout_binary(struct linux_binprm *bprm)
#endif
if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) {
- loff_t pos = fd_offset;
-
vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
- bprm->file->f_op->read(bprm->file,
- (char __user *)N_TXTADDR(ex),
- ex.a_text+ex.a_data, &pos);
- flush_icache_range((unsigned long) N_TXTADDR(ex),
- (unsigned long) N_TXTADDR(ex) +
- ex.a_text+ex.a_data);
+ read_code(bprm->file, N_TXTADDR(ex), fd_offset,
+ ex.a_text+ex.a_data);
goto beyond_if;
}
@@ -452,8 +440,6 @@ static int load_aout_library(struct file *file)
start_addr = ex.a_entry & 0xfffff000;
if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
- loff_t pos = N_TXTOFF(ex);
-
#ifdef WARN_OLD
static unsigned long error_time;
if (time_after(jiffies, error_time + 5*HZ)) {
@@ -466,12 +452,8 @@ static int load_aout_library(struct file *file)
#endif
vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
- file->f_op->read(file, (char __user *)start_addr,
- ex.a_text + ex.a_data, &pos);
- flush_icache_range((unsigned long) start_addr,
- (unsigned long) start_addr + ex.a_text +
- ex.a_data);
-
+ read_code(file, start_addr, N_TXTOFF(ex),
+ ex.a_text + ex.a_data);
retval = 0;
goto out;
}
diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index bbc8f8827eac..b23253df8756 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -287,15 +287,12 @@ static int load_aout_binary(struct linux_binprm * bprm)
return error;
}
- error = bprm->file->f_op->read(bprm->file,
- (char __user *)text_addr,
- ex.a_text+ex.a_data, &pos);
+ error = read_code(bprm->file, text_addr, pos,
+ ex.a_text+ex.a_data);
if ((signed long)error < 0) {
send_sig(SIGKILL, current, 0);
return error;
}
-
- flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
} else {
if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
(N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
@@ -311,14 +308,9 @@ static int load_aout_binary(struct linux_binprm * bprm)
}
if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
- loff_t pos = fd_offset;
vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
- bprm->file->f_op->read(bprm->file,
- (char __user *)N_TXTADDR(ex),
- ex.a_text+ex.a_data, &pos);
- flush_icache_range((unsigned long) N_TXTADDR(ex),
- (unsigned long) N_TXTADDR(ex) +
- ex.a_text+ex.a_data);
+ read_code(bprm->file, N_TXTADDR(ex), fd_offset,
+ ex.a_text + ex.a_data);
goto beyond_if;
}
@@ -397,8 +389,6 @@ static int load_aout_library(struct file *file)
start_addr = ex.a_entry & 0xfffff000;
if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
- loff_t pos = N_TXTOFF(ex);
-
if (printk_ratelimit())
{
printk(KERN_WARNING
@@ -407,11 +397,8 @@ static int load_aout_library(struct file *file)
}
vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
- file->f_op->read(file, (char __user *)start_addr,
- ex.a_text + ex.a_data, &pos);
- flush_icache_range((unsigned long) start_addr,
- (unsigned long) start_addr + ex.a_text + ex.a_data);
-
+ read_code(file, start_addr, N_TXTOFF(ex),
+ ex.a_text + ex.a_data);
retval = 0;
goto out;
}
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 9c13e023e2b7..2711d9901632 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -926,7 +926,6 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
struct elf32_fdpic_loadseg *seg;
struct elf32_phdr *phdr;
unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
- loff_t fpos;
int loop, ret;
load_addr = params->load_addr;
@@ -964,14 +963,12 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
if (params->phdrs[loop].p_type != PT_LOAD)
continue;
- fpos = phdr->p_offset;
-
seg->addr = maddr + (phdr->p_vaddr - base);
seg->p_vaddr = phdr->p_vaddr;
seg->p_memsz = phdr->p_memsz;
- ret = file->f_op->read(file, (void *) seg->addr,
- phdr->p_filesz, &fpos);
+ ret = read_code(file, seg->addr, phdr->p_offset,
+ phdr->p_filesz);
if (ret < 0)
return ret;
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 2036d21baaef..d50bbe59da1e 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -207,11 +207,12 @@ static int decompress_exec(
/* Read in first chunk of data and parse gzip header. */
fpos = offset;
- ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+ ret = kernel_read(bprm->file, offset, buf, LBUFSIZE);
strm.next_in = buf;
strm.avail_in = ret;
strm.total_in = 0;
+ fpos += ret;
retval = -ENOEXEC;
@@ -277,7 +278,7 @@ static int decompress_exec(
}
while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
- ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+ ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE);
if (ret <= 0)
break;
len -= ret;
@@ -285,6 +286,7 @@ static int decompress_exec(
strm.next_in = buf;
strm.avail_in = ret;
strm.total_in = 0;
+ fpos += ret;
}
if (ret < 0) {
@@ -428,6 +430,7 @@ static int load_flat_file(struct linux_binprm * bprm,
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;
@@ -451,6 +454,7 @@ static int load_flat_file(struct linux_binprm * bprm,
relocs = ntohl(hdr->reloc_count);
flags = ntohl(hdr->flags);
rev = ntohl(hdr->rev);
+ full_data = data_len + relocs * sizeof(unsigned long);
if (strncmp(hdr->magic, "bFLT", 4)) {
/*
@@ -577,12 +581,12 @@ static int load_flat_file(struct linux_binprm * bprm,
#ifdef CONFIG_BINFMT_ZFLAT
if (flags & FLAT_FLAG_GZDATA) {
result = decompress_exec(bprm, fpos, (char *) datapos,
- data_len + (relocs * sizeof(unsigned long)), 0);
+ full_data, 0);
} else
#endif
{
- result = bprm->file->f_op->read(bprm->file, (char *) datapos,
- data_len + (relocs * sizeof(unsigned long)), &fpos);
+ result = read_code(bprm->file, datapos, fpos,
+ full_data);
}
if (IS_ERR_VALUE(result)) {
printk("Unable to read data+bss, errno %d\n", (int)-result);
@@ -627,30 +631,25 @@ static int load_flat_file(struct linux_binprm * bprm,
if (flags & FLAT_FLAG_GZIP) {
result = decompress_exec(bprm, sizeof (struct flat_hdr),
(((char *) textpos) + sizeof (struct flat_hdr)),
- (text_len + data_len + (relocs * sizeof(unsigned long))
+ (text_len + full_data
- sizeof (struct flat_hdr)),
0);
memmove((void *) datapos, (void *) realdatastart,
- data_len + (relocs * sizeof(unsigned long)));
+ full_data);
} else if (flags & FLAT_FLAG_GZDATA) {
- fpos = 0;
- result = bprm->file->f_op->read(bprm->file,
- (char *) textpos, text_len, &fpos);
+ result = read_code(bprm->file, textpos, 0, text_len);
if (!IS_ERR_VALUE(result))
result = decompress_exec(bprm, text_len, (char *) datapos,
- data_len + (relocs * sizeof(unsigned long)), 0);
+ full_data, 0);
}
else
#endif
{
- fpos = 0;
- result = bprm->file->f_op->read(bprm->file,
- (char *) textpos, text_len, &fpos);
- if (!IS_ERR_VALUE(result)) {
- fpos = ntohl(hdr->data_start);
- result = bprm->file->f_op->read(bprm->file, (char *) datapos,
- data_len + (relocs * sizeof(unsigned long)), &fpos);
- }
+ result = read_code(bprm->file, textpos, 0, text_len);
+ if (!IS_ERR_VALUE(result))
+ result = read_code(bprm->file, datapos,
+ ntohl(hdr->data_start),
+ full_data);
}
if (IS_ERR_VALUE(result)) {
printk("Unable to read code+data+bss, errno %d\n",(int)-result);
diff --git a/fs/exec.c b/fs/exec.c
index a96a4885bbbf..77dc9096440f 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -802,6 +802,15 @@ int kernel_read(struct file *file, loff_t offset,
EXPORT_SYMBOL(kernel_read);
+ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
+{
+ ssize_t res = file->f_op->read(file, (void __user *)addr, len, &pos);
+ if (res > 0)
+ flush_icache_range(addr, addr + len);
+ return res;
+}
+EXPORT_SYMBOL(read_code);
+
static int exec_mmap(struct mm_struct *mm)
{
struct task_struct *tsk;
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index c3a09149f793..70cf138690e9 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -118,5 +118,6 @@ extern int prepare_bprm_creds(struct linux_binprm *bprm);
extern void install_exec_creds(struct linux_binprm *bprm);
extern void set_binfmt(struct linux_binfmt *new);
extern void free_bprm(struct linux_binprm *);
+extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
#endif /* _LINUX_BINFMTS_H */
--
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