[PATCH] flat binary loader doesn't check fd table full
In binfmt_flat.c, the flat binary loader should check file descriptor table
and install the fd on the file.
Convert the function to single-exit and fix this bug.
Signed-off-by: "Luke Yang" <luke.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 108d56bb..69f44dc 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -36,6 +36,7 @@
#include <linux/personality.h>
#include <linux/init.h>
#include <linux/flat.h>
+#include <linux/syscalls.h>
#include <asm/byteorder.h>
#include <asm/system.h>
@@ -426,6 +427,8 @@
int i, rev, relocs = 0;
loff_t fpos;
unsigned long start_code, end_code;
+ int ret;
+ int exec_fileno;
hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
inode = bprm->file->f_dentry->d_inode;
@@ -450,7 +453,8 @@
*/
if (strncmp(hdr->magic, "#!", 2))
printk("BINFMT_FLAT: bad header magic\n");
- return -ENOEXEC;
+ ret = -ENOEXEC;
+ goto err;
}
if (flags & FLAT_FLAG_KTRACE)
@@ -458,14 +462,16 @@
if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
printk("BINFMT_FLAT: bad flat file version 0x%x (supported 0x%x and 0x%x)\n", rev, FLAT_VERSION, OLD_FLAT_VERSION);
- return -ENOEXEC;
+ 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);
- return -ENOEXEC;
+ ret = -ENOEXEC;
+ goto err;
}
/*
@@ -478,7 +484,8 @@
#ifndef CONFIG_BINFMT_ZFLAT
if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
printk("Support for ZFLAT executables is not enabled.\n");
- return -ENOEXEC;
+ ret = -ENOEXEC;
+ goto err;
}
#endif
@@ -490,14 +497,27 @@
rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
if (rlim >= RLIM_INFINITY)
rlim = ~0;
- if (data_len + bss_len > rlim)
- return -ENOMEM;
+ if (data_len + bss_len > rlim) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ /* check file descriptor */
+ exec_fileno = get_unused_fd();
+ if (exec_fileno < 0) {
+ ret = -EMFILE;
+ goto err;
+ }
+ get_file(bprm->file);
+ fd_install(exec_fileno, bprm->file);
/* Flush all traces of the currently running executable */
if (id == 0) {
result = flush_old_exec(bprm);
- if (result)
- return result;
+ if (result) {
+ ret = result;
+ goto err_close;
+ }
/* OK, This is the point of no return */
set_personality(PER_LINUX);
@@ -527,7 +547,8 @@
if (!textpos)
textpos = (unsigned long) -ENOMEM;
printk("Unable to mmap process text, errno %d\n", (int)-textpos);
- return(textpos);
+ ret = textpos;
+ goto err_close;
}
down_write(¤t->mm->mmap_sem);
@@ -542,7 +563,8 @@
printk("Unable to allocate RAM for process data, errno %d\n",
(int)-datapos);
do_munmap(current->mm, textpos, text_len);
- return realdatastart;
+ ret = realdatastart;
+ goto err_close;
}
datapos = realdatastart + MAX_SHARED_LIBS * sizeof(unsigned long);
@@ -564,7 +586,8 @@
printk("Unable to read data+bss, errno %d\n", (int)-result);
do_munmap(current->mm, textpos, text_len);
do_munmap(current->mm, realdatastart, data_len + extra);
- return result;
+ ret = result;
+ goto err_close;
}
reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
@@ -582,7 +605,8 @@
textpos = (unsigned long) -ENOMEM;
printk("Unable to allocate RAM for process text/data, errno %d\n",
(int)-textpos);
- return(textpos);
+ ret = textpos;
+ goto err_close;
}
realdatastart = textpos + ntohl(hdr->data_start);
@@ -627,7 +651,8 @@
printk("Unable to read code+data+bss, errno %d\n",(int)-result);
do_munmap(current->mm, textpos, text_len + data_len + extra +
MAX_SHARED_LIBS * sizeof(unsigned long));
- return result;
+ ret = result;
+ goto err_close;
}
}
@@ -690,8 +715,10 @@
unsigned long addr;
if (*rp) {
addr = calc_reloc(*rp, libinfo, id, 0);
- if (addr == RELOC_FAILED)
- return -ENOEXEC;
+ if (addr == RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err_close;
+ }
*rp = addr;
}
}
@@ -718,8 +745,10 @@
relval = ntohl(reloc[i]);
addr = flat_get_relocate_addr(relval);
rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
- if (rp == (unsigned long *)RELOC_FAILED)
- return -ENOEXEC;
+ if (rp == (unsigned long *)RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err_close;
+ }
/* Get the pointer's value. */
addr = flat_get_addr_from_rp(rp, relval, flags);
@@ -731,8 +760,10 @@
if ((flags & FLAT_FLAG_GOTPIC) == 0)
addr = ntohl(addr);
addr = calc_reloc(addr, libinfo, id, 0);
- if (addr == RELOC_FAILED)
- return -ENOEXEC;
+ if (addr == RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err_close;
+ }
/* Write back the relocated pointer. */
flat_put_addr_at_rp(rp, addr, relval);
@@ -752,6 +783,10 @@
stack_len);
return 0;
+err_close:
+ sys_close(exec_fileno);
+err:
+ return ret;
}