File 0028-linux-user-lseek-explicitly-cast-no.patch of Package qemu

Overview Repositories Revisions Requests Users Attributes Meta

File 0028-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision 0dd6646b276b29e12c33a060593614fd)

Currently displaying revision 0dd6646b276b29e12c33a060593614fd , Show latest

From fd4fc533fbd24b003f606d12bd114ff9ba215380 Mon Sep 17 00:00:00 2001
From: Alexander Graf <agraf@suse.de>
Date: Thu, 13 Dec 2012 14:29:22 +0100
Subject: [PATCH] linux-user: lseek: explicitly cast non-set offsets to signed

When doing lseek, SEEK_SET indicates that the offset is an unsigned variable.
Other seek types have parameters that can be negative.

When converting from 32bit to 64bit parameters, we need to take this into
account and enable SEEK_END and SEEK_CUR to be negative, while SEEK_SET stays
absolute positioned which we need to maintain as unsigned.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 linux-user/syscall.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 8ac1281..51c1091 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -7710,9 +7710,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_ulong arg1,
     case TARGET_NR_oldstat:
         goto unimplemented;
 #endif
-    case TARGET_NR_lseek:
-        ret = get_errno(lseek(arg1, arg2, arg3));
+    case TARGET_NR_lseek: {
+        off_t off = arg2;
+        if (arg3 != SEEK_SET) {
+            off = (abi_long)arg2;
+        }
+        ret = get_errno(lseek(arg1, off, arg3));
         break;
+    }
 #if defined(TARGET_NR_getxpid) && defined(TARGET_ALPHA)
     /* Alpha specific */
     case TARGET_NR_getxpid:

Places

File 0028-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision 0dd6646b276b29e12c33a060593614fd)

Places