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| author | Michal Simek <michal.simek@xilinx.com> | 2013-03-28 16:42:44 +0100 |
|---|---|---|
| committer | Michal Simek <michal.simek@xilinx.com> | 2013-05-09 09:04:32 +0200 |
| commit | f663b60f5215b44d147ee0c07d17ffd7e9f3f881 (patch) | |
| tree | def7dc04d57d626adbf66a8eedef49a09bb8c9a1 /arch/microblaze | |
| parent | 6dc92c9c3f209cb07fbf282b470ed76787bbc5f8 (diff) | |
| download | linux-f663b60f5215b44d147ee0c07d17ffd7e9f3f881.tar.gz linux-f663b60f5215b44d147ee0c07d17ffd7e9f3f881.tar.bz2 linux-f663b60f5215b44d147ee0c07d17ffd7e9f3f881.zip | |
microblaze: Fix uaccess_ok macro
Fix access_ok macro no to permit
case where user will try to access
the last address space which is equal
to segment address.
Example:
segment addr = 0xbfff ffff
address = 0xbfff fff0
size = 0x10
Current wrong implementation
0xbfff ffff >= (0xbfff fff0 | 0x10 | (0xbfff fff0 + 0x10))
0xbfff ffff >= (0xbfff fff0 | 0xc000 0000)
0xbfff ffff >= 0xf000 0000
return 0 which is access failed even the combination is valid.
because get_fs().seq returns the last valid address.
This patch fix this problem.
Size equals to zero is valid access.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Diffstat (limited to 'arch/microblaze')
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 30 |
1 files changed, 19 insertions, 11 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index a1ab5f0009ef..efe59d881789 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -90,17 +90,25 @@ static inline int ___range_ok(unsigned long addr, unsigned long size) #else -/* - * Address is valid if: - * - "addr", "addr + size" and "size" are all below the limit - */ -#define access_ok(type, addr, size) \ - (get_fs().seg >= (((unsigned long)(addr)) | \ - (size) | ((unsigned long)(addr) + (size)))) - -/* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n", - type?"WRITE":"READ",addr,size,get_fs().seg)) */ - +static inline int access_ok(int type, const void __user *addr, + unsigned long size) +{ + if (!size) + goto ok; + + if ((get_fs().seg < ((unsigned long)addr)) || + (get_fs().seg < ((unsigned long)addr + size - 1))) { + pr_debug("ACCESS fail: %s at 0x%08x (size 0x%x), seg 0x%08x\n", + type ? "WRITE" : "READ ", (u32)addr, (u32)size, + (u32)get_fs().seg); + return 0; + } +ok: + pr_debug("ACCESS OK: %s at 0x%08x (size 0x%x), seg 0x%08x\n", + type ? "WRITE" : "READ ", (u32)addr, (u32)size, + (u32)get_fs().seg); + return 1; +} #endif #ifdef CONFIG_MMU |