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

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File 0028-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision e21857af0410d5d2df4be276bd297082)

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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:

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File 0028-linux-user-lseek-explicitly-cast-no.patch of Package qemu (Revision e21857af0410d5d2df4be276bd297082)

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