[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH] fix read() and acct() on NULL arguments
From: |
Riku Voipio |
Subject: |
[Qemu-devel] [PATCH] fix read() and acct() on NULL arguments |
Date: |
Mon, 19 Jan 2009 17:29:12 +0200 |
User-agent: |
Mutt/1.5.11+cvs20060126 |
Returning efault in these cases is not correct. Originally
proposed by Thayne Harbaugh in 2007:
http://www.mail-archive.com/address@hidden/msg14658.html
Signed-off-by: Riku Voipio <address@hidden>
---
linux-user/syscall.c | 24 ++++++++++++++++--------
1 files changed, 16 insertions(+), 8 deletions(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 4eb003a..ab81b3a 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3713,10 +3713,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
arg1,
ret = 0; /* avoid warning */
break;
case TARGET_NR_read:
- if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
- goto efault;
- ret = get_errno(read(arg1, p, arg3));
- unlock_user(p, arg2, ret);
+ if (arg3 == 0)
+ ret = 0;
+ else {
+ if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
+ goto efault;
+ ret = get_errno(read(arg1, p, arg3));
+ unlock_user(p, arg2, ret);
+ }
break;
case TARGET_NR_write:
if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
@@ -4217,10 +4221,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
arg1,
goto unimplemented;
#endif
case TARGET_NR_acct:
- if (!(p = lock_user_string(arg1)))
- goto efault;
- ret = get_errno(acct(path(p)));
- unlock_user(p, arg1, 0);
+ if (arg1 == 0) {
+ ret = get_errno(acct(NULL));
+ } else {
+ if (!(p = lock_user_string(arg1)))
+ goto efault;
+ ret = get_errno(acct(path(p)));
+ unlock_user(p, arg1, 0);
+ }
break;
#ifdef TARGET_NR_umount2 /* not on alpha */
case TARGET_NR_umount2:
--
1.5.6.5
--
"rm -rf" only sounds scary if you don't have backups
- [Qemu-devel] [PATCH] fix read() and acct() on NULL arguments,
Riku Voipio <=