[PATCH v2 1/2] binfmt_aout: x86: Useless inode var, printks coding style fixes

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file size used only once, so removed due its useless prior allocation.
It's not necessary to verify f_op in the load_aout_library, since the
prior kernel_read/vfs_read function already does.
Made coding style fixes and printk replacements.

Tested using qemu, a handcrafted a.out binary and a a.out linked with a
cross-compiled ld.

Signed-off-by: Geyslan G. Bem <geyslan@xxxxxxxxx>
---
 fs/binfmt_aout.c | 98 +++++++++++++++++++++++++++-----------------------------
 1 file changed, 48 insertions(+), 50 deletions(-)

diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index 89dec7f..c732b8e 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -25,13 +25,14 @@
 #include <linux/init.h>
 #include <linux/coredump.h>
 #include <linux/slab.h>
+#include <linux/ratelimit.h>
+#include <linux/uaccess.h>
 
-#include <asm/uaccess.h>
 #include <asm/cacheflush.h>
 #include <asm/a.out-core.h>
 
 static int load_aout_binary(struct linux_binprm *);
-static int load_aout_library(struct file*);
+static int load_aout_library(struct file *);
 
 #ifdef CONFIG_COREDUMP
 /*
@@ -62,7 +63,7 @@ static int aout_core_dump(struct coredump_params *cprm)
 	fs = get_fs();
 	set_fs(KERNEL_DS);
 	has_dumped = 1;
-       	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
+	strncpy(dump.u_comm, current->comm, sizeof(dump.u_comm));
 	dump.u_ar0 = offsetof(struct user, regs);
 	dump.signal = cprm->siginfo->si_signo;
 	aout_dump_thread(cprm->regs, &dump);
@@ -78,9 +79,11 @@ static int aout_core_dump(struct coredump_params *cprm)
 
 /* make sure we actually have a data and stack area to dump */
 	set_fs(USER_DS);
-	if (!access_ok(VERIFY_READ, START_DATA(dump), dump.u_dsize << PAGE_SHIFT))
+	if (!access_ok(VERIFY_READ, START_DATA(dump),
+		       dump.u_dsize << PAGE_SHIFT))
 		dump.u_dsize = 0;
-	if (!access_ok(VERIFY_READ, START_STACK(dump), dump.u_ssize << PAGE_SHIFT))
+	if (!access_ok(VERIFY_READ, START_STACK(dump),
+		       dump.u_ssize << PAGE_SHIFT))
 		dump.u_ssize = 0;
 
 	set_fs(KERNEL_DS);
@@ -142,7 +145,8 @@ static int set_brk(unsigned long start, unsigned long end)
  * memory and creates the pointer tables from them, and puts their
  * addresses on the "stack", returning the new stack pointer value.
  */
-static unsigned long __user *create_aout_tables(char __user *p, struct linux_binprm * bprm)
+static unsigned long __user *create_aout_tables(char __user *p,
+						struct linux_binprm *bprm)
 {
 	char __user * __user *argv;
 	char __user * __user *envp;
@@ -150,7 +154,8 @@ static unsigned long __user *create_aout_tables(char __user *p, struct linux_bin
 	int argc = bprm->argc;
 	int envc = bprm->envc;
 
-	sp = (void __user *)((-(unsigned long)sizeof(char *)) & (unsigned long) p);
+	sp = (void __user *) ((-(unsigned long) sizeof(char *))
+			      & (unsigned long) p);
 #ifdef __alpha__
 /* whee.. test-programs are so much fun. */
 	put_user(0, --sp);
@@ -169,28 +174,28 @@ static unsigned long __user *create_aout_tables(char __user *p, struct linux_bin
 	sp -= argc+1;
 	argv = (char __user * __user *) sp;
 #ifndef __alpha__
-	put_user((unsigned long) envp,--sp);
-	put_user((unsigned long) argv,--sp);
+	put_user((unsigned long) envp, --sp);
+	put_user((unsigned long) argv, --sp);
 #endif
-	put_user(argc,--sp);
+	put_user(argc, --sp);
 	current->mm->arg_start = (unsigned long) p;
-	while (argc-->0) {
+	while (argc-- > 0) {
 		char c;
-		put_user(p,argv++);
+		put_user(p, argv++);
 		do {
-			get_user(c,p++);
+			get_user(c, p++);
 		} while (c);
 	}
-	put_user(NULL,argv);
+	put_user(NULL, argv);
 	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
-	while (envc-->0) {
+	while (envc-- > 0) {
 		char c;
-		put_user(p,envp++);
+		put_user(p, envp++);
 		do {
-			get_user(c,p++);
+			get_user(c, p++);
 		} while (c);
 	}
-	put_user(NULL,envp);
+	put_user(NULL, envp);
 	current->mm->env_end = (unsigned long) p;
 	return sp;
 }
@@ -200,7 +205,7 @@ static unsigned long __user *create_aout_tables(char __user *p, struct linux_bin
  * libraries.  There is no binary dependent code anywhere else.
  */
 
-static int load_aout_binary(struct linux_binprm * bprm)
+static int load_aout_binary(struct linux_binprm *bprm)
 {
 	struct pt_regs *regs = current_pt_regs();
 	struct exec ex;
@@ -213,7 +218,8 @@ static int load_aout_binary(struct linux_binprm * bprm)
 	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(file_inode(bprm->file)) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
+	    i_size_read(file_inode(bprm->file)) <
+	    ex.a_text + ex.a_data + N_SYMSIZE(ex) + N_TXTOFF(ex)) {
 		return -ENOEXEC;
 	}
 
@@ -292,19 +298,12 @@ static int load_aout_binary(struct linux_binprm * bprm)
 		}
 	} else {
 		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
-		    (N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
-		{
-			printk(KERN_NOTICE "executable not page aligned\n");
-		}
-
-		if ((fd_offset & ~PAGE_MASK) != 0 && printk_ratelimit())
-		{
-			printk(KERN_WARNING 
-			       "fd_offset is not page aligned. Please convert program: %s\n",
-			       bprm->file->f_path.dentry->d_name.name);
-		}
+		    (N_MAGIC(ex) != NMAGIC))
+			pr_notice_ratelimited("executable not page aligned\n");
 
-		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
+		if ((fd_offset & ~PAGE_MASK) != 0) {
+			pr_warn_ratelimited("fd_offset is not page aligned. Please convert program: %s\n",
+					    bprm->file->f_path.dentry->d_name.name);
 			vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
 			read_code(bprm->file, N_TXTADDR(ex), fd_offset,
 				  ex.a_text + ex.a_data);
@@ -312,9 +311,10 @@ static int load_aout_binary(struct linux_binprm * bprm)
 		}
 
 		error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text,
-			PROT_READ | PROT_EXEC,
-			MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
-			fd_offset);
+				PROT_READ | PROT_EXEC,
+				(MAP_FIXED | MAP_PRIVATE
+				 | MAP_DENYWRITE | MAP_EXECUTABLE),
+				fd_offset);
 
 		if (error != N_TXTADDR(ex)) {
 			send_sig(SIGKILL, current, 0);
@@ -323,8 +323,10 @@ static int load_aout_binary(struct linux_binprm * bprm)
 
 		error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data,
 				PROT_READ | PROT_WRITE | PROT_EXEC,
-				MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,
+				(MAP_FIXED | MAP_PRIVATE
+				 | MAP_DENYWRITE | MAP_EXECUTABLE),
 				fd_offset + ex.a_text);
+
 		if (error != N_DATADDR(ex)) {
 			send_sig(SIGKILL, current, 0);
 			return error;
@@ -340,7 +342,8 @@ beyond_if:
 	}
 
 	current->mm->start_stack =
-		(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
+		(unsigned long) create_aout_tables((char __user *) bprm->p,
+						   bprm);
 #ifdef __alpha__
 	regs->gp = ex.a_gpvalue;
 #endif
@@ -350,14 +353,11 @@ beyond_if:
 
 static int load_aout_library(struct file *file)
 {
-	struct inode * inode;
 	unsigned long bss, start_addr, len;
 	unsigned long error;
 	int retval;
 	struct exec ex;
 
-	inode = file_inode(file);
-
 	retval = -ENOEXEC;
 	error = kernel_read(file, 0, (char *) &ex, sizeof(ex));
 	if (error != sizeof(ex))
@@ -366,7 +366,8 @@ static int load_aout_library(struct file *file)
 	/* We come in here for the regular a.out style of shared libraries */
 	if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||
 	    N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||
-	    i_size_read(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
+	    i_size_read(file_inode(file)) <
+	    ex.a_text + ex.a_data + N_SYMSIZE(ex) + N_TXTOFF(ex)) {
 		goto out;
 	}
 
@@ -374,7 +375,7 @@ static int load_aout_library(struct file *file)
 	 * 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)
+	if (!file->f_op->mmap)
 		goto out;
 
 	if (N_FLAGS(ex))
@@ -383,17 +384,14 @@ static int load_aout_library(struct file *file)
 	/* For  QMAGIC, the starting address is 0x20 into the page.  We mask
 	   this off to get the starting address for the page */
 
-	start_addr =  ex.a_entry & 0xfffff000;
+	start_addr = ex.a_entry & 0xfffff000;
 
 	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
-		if (printk_ratelimit())
-		{
-			printk(KERN_WARNING 
-			       "N_TXTOFF is not page aligned. Please convert library: %s\n",
-			       file->f_path.dentry->d_name.name);
-		}
+		pr_warn_ratelimited("N_TXTOFF is not page aligned. Please convert library: %s\n",
+				    file->f_path.dentry->d_name.name);
+
 		vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
-		
+
 		read_code(file, start_addr, N_TXTOFF(ex),
 			  ex.a_text + ex.a_data);
 		retval = 0;
-- 
1.8.4

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