File 0031-linux-user-lseek-explicitly-cast-no.patch of Package qemu.3829

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File 0031-linux-user-lseek-explicitly-cast-no.patch of Package qemu.3829 (Revision 822a918436a71ff0a8333c74d5ad78ca)

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From de548138fc0b54aef5ae8017a9cbe1e45111a870 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 ebeab57f9e..c084f38490 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6233,9 +6233,14 @@ 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:

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File 0031-linux-user-lseek-explicitly-cast-no.patch of Package qemu.3829 (Revision 822a918436a71ff0a8333c74d5ad78ca)

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