diff options
author | Helge Deller <deller@gmx.de> | 2013-11-20 23:07:42 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-11 22:37:54 -0800 |
commit | 527c106d547866865ec9368f913b25f530f9f2a5 (patch) | |
tree | b4c134145aa34d356cca49ba21b4506e5bdbeffa /arch/parisc | |
parent | 8dd478f2d7480ce2ba7e1fa89d00049fb03b6b94 (diff) |
parisc: fix mmap(MAP_FIXED|MAP_SHARED) to already mmapped address
commit 0576da2c08e3d332f1b0653030d28ab804585ab6 upstream.
locale-gen on Debian showed a strange problem on parisc:
mmap2(NULL, 536870912, PROT_NONE, MAP_SHARED, 3, 0) = 0x42a54000
mmap2(0x42a54000, 103860, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, 3, 0) = -1 EINVAL (Invalid argument)
Basically it was just trying to re-mmap() a file at the same address
which it was given by a previous mmap() call. But this remapping failed
with EINVAL.
The problem is, that when MAP_FIXED and MAP_SHARED flags were used, we didn't
included the mapping-based offset when we verified the alignment of the given
fixed address against the offset which we calculated it in the previous call.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/parisc')
-rw-r--r-- | arch/parisc/kernel/sys_parisc.c | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index 5dfd248e3f1a..0d3a9d4927b5 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -61,8 +61,15 @@ static int get_offset(struct address_space *mapping) return (unsigned long) mapping >> 8; } -static unsigned long get_shared_area(struct address_space *mapping, - unsigned long addr, unsigned long len, unsigned long pgoff) +static unsigned long shared_align_offset(struct file *filp, unsigned long pgoff) +{ + struct address_space *mapping = filp ? filp->f_mapping : NULL; + + return (get_offset(mapping) + pgoff) << PAGE_SHIFT; +} + +static unsigned long get_shared_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff) { struct vm_unmapped_area_info info; @@ -71,7 +78,7 @@ static unsigned long get_shared_area(struct address_space *mapping, info.low_limit = PAGE_ALIGN(addr); info.high_limit = TASK_SIZE; info.align_mask = PAGE_MASK & (SHMLBA - 1); - info.align_offset = (get_offset(mapping) + pgoff) << PAGE_SHIFT; + info.align_offset = shared_align_offset(filp, pgoff); return vm_unmapped_area(&info); } @@ -82,20 +89,18 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, return -ENOMEM; if (flags & MAP_FIXED) { if ((flags & MAP_SHARED) && - (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)) + (addr - shared_align_offset(filp, pgoff)) & (SHMLBA - 1)) return -EINVAL; return addr; } if (!addr) addr = TASK_UNMAPPED_BASE; - if (filp) { - addr = get_shared_area(filp->f_mapping, addr, len, pgoff); - } else if(flags & MAP_SHARED) { - addr = get_shared_area(NULL, addr, len, pgoff); - } else { + if (filp || (flags & MAP_SHARED)) + addr = get_shared_area(filp, addr, len, pgoff); + else addr = get_unshared_area(addr, len); - } + return addr; } |