File 0013-linux-user-lseek-explicitly-cast-no.patch of Package qemu

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File 0013-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision 95b278d20ec699048440c083f804d4a7)

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From 8c551cc70f35d5aee57fc4da9e58c81d8fec26b5 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 c2f2cb10b9..b743694853 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -8396,9 +8396,14 @@ 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 0013-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision 95b278d20ec699048440c083f804d4a7)

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