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From 98014e4b27063ed74313878233e91b7b52b2a031 Mon Sep 17 00:00:00 2001
From: Will Springer <skirmisher@protonmail.com>
Date: Tue, 9 Jun 2020 02:11:36 -0700
Subject: [PATCH] powerpc/compat32: swap hi/lo parts of 64-bit syscall args on
32LE
This allows compat_sys calls with 64-bit args to function correctly
when called by ppcle userlands on ppc64le.
Tested with `file /bin/bash` (pread64) and `truncate -s 5G test` (ftruncate64).
---
arch/powerpc/kernel/sys_ppc32.c | 49 +++++++++++++++++++--------------
1 file changed, 28 insertions(+), 21 deletions(-)
diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c
index d36c6391eaf5..16ff0399a257 100644
--- a/arch/powerpc/kernel/sys_ppc32.c
+++ b/arch/powerpc/kernel/sys_ppc32.c
@@ -59,57 +59,64 @@ unsigned long compat_sys_mmap2(unsigned long addr, size_t len,
/*
* long long munging:
* The 32 bit ABI passes long longs in an odd even register pair.
+ * High and low parts are swapped depending on endian mode,
+ * so define a macro (similar to mips linux32) to handle that.
*/
+#ifdef __LITTLE_ENDIAN__
+#define merge_64(low, high) ((u64)high << 32) | low
+#else
+#define merge_64(high, low) ((u64)high << 32) | low
+#endif
compat_ssize_t compat_sys_pread64(unsigned int fd, char __user *ubuf, compat_size_t count,
- u32 reg6, u32 poshi, u32 poslo)
+ u32 reg6, u32 pos1, u32 pos2)
{
- return ksys_pread64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);
+ return ksys_pread64(fd, ubuf, count, merge_64(pos1, pos2));
}
compat_ssize_t compat_sys_pwrite64(unsigned int fd, const char __user *ubuf, compat_size_t count,
- u32 reg6, u32 poshi, u32 poslo)
+ u32 reg6, u32 pos1, u32 pos2)
{
- return ksys_pwrite64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);
+ return ksys_pwrite64(fd, ubuf, count, merge_64(pos1, pos2));
}
-compat_ssize_t compat_sys_readahead(int fd, u32 r4, u32 offhi, u32 offlo, u32 count)
+compat_ssize_t compat_sys_readahead(int fd, u32 r4, u32 offset1, u32 offset2, u32 count)
{
- return ksys_readahead(fd, ((loff_t)offhi << 32) | offlo, count);
+ return ksys_readahead(fd, merge_64(offset1, offset2), count);
}
asmlinkage int compat_sys_truncate64(const char __user * path, u32 reg4,
- unsigned long high, unsigned long low)
+ unsigned long len1, unsigned long len2)
{
- return ksys_truncate(path, (high << 32) | low);
+ return ksys_truncate(path, merge_64(len1, len2));
}
-asmlinkage long compat_sys_fallocate(int fd, int mode, u32 offhi, u32 offlo,
- u32 lenhi, u32 lenlo)
+asmlinkage long compat_sys_fallocate(int fd, int mode, u32 offset1, u32 offset2,
+ u32 len1, u32 len2)
{
- return ksys_fallocate(fd, mode, ((loff_t)offhi << 32) | offlo,
- ((loff_t)lenhi << 32) | lenlo);
+ return ksys_fallocate(fd, mode, ((loff_t)offset1 << 32) | offset2,
+ merge_64(len1, len2));
}
-asmlinkage int compat_sys_ftruncate64(unsigned int fd, u32 reg4, unsigned long high,
- unsigned long low)
+asmlinkage int compat_sys_ftruncate64(unsigned int fd, u32 reg4, unsigned long len1,
+ unsigned long len2)
{
- return ksys_ftruncate(fd, (high << 32) | low);
+ return ksys_ftruncate(fd, merge_64(len1, len2));
}
-long ppc32_fadvise64(int fd, u32 unused, u32 offset_high, u32 offset_low,
+long ppc32_fadvise64(int fd, u32 unused, u32 offset1, u32 offset2,
size_t len, int advice)
{
- return ksys_fadvise64_64(fd, (u64)offset_high << 32 | offset_low, len,
+ return ksys_fadvise64_64(fd, merge_64(offset1, offset2), len,
advice);
}
asmlinkage long compat_sys_sync_file_range2(int fd, unsigned int flags,
- unsigned offset_hi, unsigned offset_lo,
- unsigned nbytes_hi, unsigned nbytes_lo)
+ unsigned offset1, unsigned offset2,
+ unsigned nbytes1, unsigned nbytes2)
{
- loff_t offset = ((loff_t)offset_hi << 32) | offset_lo;
- loff_t nbytes = ((loff_t)nbytes_hi << 32) | nbytes_lo;
+ loff_t offset = merge_64(offset1, offset2);
+ loff_t nbytes = merge_64(nbytes1, nbytes2);
return ksys_sync_file_range(fd, offset, nbytes, flags);
}
--
2.26.2
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