X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;ds=sidebyside;f=fs%2Fbinfmt_aout.c;h=be6dfe80ea3978f2fde2c997ba58dfe14b50592c;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=d1fe43b0161f707b5e78a0c17287475bc9b1b56c;hpb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;p=linux-2.6.git

diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index d1fe43b01..be6dfe80e 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -275,10 +275,17 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&
 	     N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) ||
 	    N_TRSIZE(ex) || N_DRSIZE(ex) ||
-	    i_size_read(bprm->file->f_dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
+	    i_size_read(bprm->file->f_path.dentry->d_inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
 		return -ENOEXEC;
 	}
 
+	/*
+	 * Requires a mmap handler. This prevents people from using a.out
+	 * as part of an exploit attack against /proc-related vulnerabilities.
+	 */
+	if (!bprm->file->f_op || !bprm->file->f_op->mmap)
+		return -ENOEXEC;
+
 	fd_offset = N_TXTOFF(ex);
 
 	/* Check initial limits. This avoids letting people circumvent
@@ -383,7 +390,7 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 		{
 			printk(KERN_WARNING 
 			       "fd_offset is not page aligned. Please convert program: %s\n",
-			       bprm->file->f_dentry->d_name.name);
+			       bprm->file->f_path.dentry->d_name.name);
 			error_time = jiffies;
 		}
 
@@ -457,7 +464,7 @@ static int load_aout_library(struct file *file)
 	int retval;
 	struct exec ex;
 
-	inode = file->f_dentry->d_inode;
+	inode = file->f_path.dentry->d_inode;
 
 	retval = -ENOEXEC;
 	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
@@ -471,6 +478,13 @@ static int load_aout_library(struct file *file)
 		goto out;
 	}
 
+	/*
+	 * Requires a mmap handler. This prevents people from using a.out
+	 * as part of an exploit attack against /proc-related vulnerabilities.
+	 */
+	if (!file->f_op || !file->f_op->mmap)
+		goto out;
+
 	if (N_FLAGS(ex))
 		goto out;
 
@@ -487,7 +501,7 @@ static int load_aout_library(struct file *file)
 		{
 			printk(KERN_WARNING 
 			       "N_TXTOFF is not page aligned. Please convert library: %s\n",
-			       file->f_dentry->d_name.name);
+			       file->f_path.dentry->d_name.name);
 			error_time = jiffies;
 		}
 		down_write(&current->mm->mmap_sem);