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2017-03-29parisc: Fix access fault handling in pa_memcpy()Helge Deller1-458/+3
pa_memcpy() is the major memcpy implementation in the parisc kernel which is used to do any kind of userspace/kernel memory copies. Al Viro noticed various bugs in the implementation of pa_mempcy(), most notably that in case of faults it may report back to have copied more bytes than it actually did. Fixing those bugs is quite hard in the C-implementation, because the compiler is messing around with the registers and we are not guaranteed that specific variables are always in the same processor registers. This makes proper fault handling complicated. This patch implements pa_memcpy() in assembler. That way we have correct fault handling and adding a 64-bit copy routine was quite easy. Runtime tested with 32- and 64bit kernels. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
2016-10-06parisc: Add hardened usercopy featureHelge Deller1-5/+6
Add hardened usercopy checks to parisc architecture and clean up indenting. Signed-off-by: Helge Deller <deller@gmx.de>
2014-04-03parisc: Replace __get_cpu_var uses for address calculationChristoph Lameter1-1/+1
Convert to the use of this_cpu_ptr(). Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Helge Deller <deller@gmx.de>
2013-11-20parisc: size_t is unsigned, so comparison size < 0 doesn't make sense.Helge Deller1-1/+1
Signed-off-by: Helge Deller <deller@gmx.de> CC: Mikulas Patocka <mpatocka@redhat.com>
2013-11-20parisc: do not inline pa_memcpy() internal functionsHelge Deller1-2/+2
gcc (4.8.x) creates wrong code when the pa_memcpy() functions are inlined. Especially in 32bit builds it calculates wrong return values if we encounter a fault during execution of the memcpy. Signed-off-by: Helge Deller <deller@gmx.de>
2013-10-13parisc: let probe_kernel_read() capture access to page zeroHelge Deller1-1/+14
Signed-off-by: Helge Deller <deller@gmx.de>
2013-07-10parisc: Fix gcc miscompilation in pa_memcpy()Helge Deller1-29/+50
When running the LTP testsuite one may hit this kernel BUG() with the write06 testcase: kernel BUG at mm/filemap.c:2023! CPU: 1 PID: 8614 Comm: writev01 Not tainted 3.10.0-rc7-64bit-c3000+ #6 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401e6e84 00000000401e6e88 IIR: 03ffe01f ISR: 0000000010340000 IOR: 000001fbe0380820 CPU: 1 CR30: 00000000bef80000 CR31: ffffffffffffffff ORIG_R28: 00000000bdc192c0 IAOQ[0]: iov_iter_advance+0x3c/0xc0 IAOQ[1]: iov_iter_advance+0x40/0xc0 RP(r2): generic_file_buffered_write+0x204/0x3f0 Backtrace: [<00000000401e764c>] generic_file_buffered_write+0x204/0x3f0 [<00000000401eab24>] __generic_file_aio_write+0x244/0x448 [<00000000401eadc0>] generic_file_aio_write+0x98/0x150 [<000000004024f460>] do_sync_readv_writev+0xc0/0x130 [<000000004025037c>] compat_do_readv_writev+0x12c/0x340 [<00000000402505f8>] compat_writev+0x68/0xa0 [<0000000040251d88>] compat_SyS_writev+0x98/0xf8 Reason for this crash is a gcc miscompilation in the fault handlers of pa_memcpy() which return the fault address instead of the copied bytes. Since this seems to be a generic problem with gcc-4.7.x (and below), it's better to simplify the fault handlers in pa_memcpy to avoid this problem. Here is a simple reproducer for the problem: int main(int argc, char **argv) { int fd, nbytes; struct iovec wr_iovec[] = { { "TEST STRING ",32}, { (char*)0x40005000,32} }; // random memory. fd = open(DATA_FILE, O_RDWR | O_CREAT, 0666); nbytes = writev(fd, wr_iovec, 2); printf("return value = %d, errno %d (%s)\n", nbytes, errno, strerror(errno)); return 0; } In addition, John David Anglin wrote: There is no gcc PR as pa_memcpy is not legitimate C code. There is an implicit assumption that certain variables will contain correct values when an exception occurs and the code randomly jumps to one of the exception blocks. There is no guarantee of this. If a PR was filed, it would likely be marked as invalid. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: John David Anglin <dave.anglin@bell.net> Cc: <stable@vger.kernel.org> # 3.8+ Signed-off-by: Helge Deller <deller@gmx.de>
2013-03-02parisc: avoid unitialized variable warning in pa_memcpy()Helge Deller1-1/+1
Avoid this warning, while still prevent gcc from optimizing away the exception code: arch/parisc/lib/memcpy.c: In function ‘pa_memcpy’: arch/parisc/lib/memcpy.c:256:2: warning: ‘dummy’ may be used uninitialized in this function [-Wuninitialized] Signed-off-by: Helge Deller <deller@gmx.de>
2010-03-07parisc: add strict copy size checks (v2)Helge Deller1-1/+2
Add CONFIG_DEBUG_STRICT_USER_COPY_CHECKS, copied from the x86 implementation. Tested with 32 and 64bit kernel. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2009-07-03parisc: fix mismatched parenthesis in memcpy.cRandolph Chung1-1/+1
>>>> I think this is what was intended? Note that this patch may affect >>>> profiling. >>> it really should be >>> >>> - if (likely(t1 & (sizeof(unsigned int)-1)) == 0) { >>> + if (likely((t1 & (sizeof(unsigned int)-1)) == 0)) { >>> >>> randolph Reported-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Randolph Chung <tausq@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2009-01-05parisc: lib/: make code staticAdrian Bunk1-1/+1
Make the following needlessly global code static: - iomap.c: struct iomap_ops[] - memcpy.c: pa_memcpy() Signed-off-by: Adrian Bunk <bunk@kernel.org> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Grant Grundler <grundler@parisc-linux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-05-15parisc: replace remaining __FUNCTION__ occurrencesHarvey Harrison1-1/+1
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@parisc-linux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2007-10-18[PARISC] parisc: "extern inline" -> "static inline"Adrian Bunk1-2/+2
"extern inline" will have different semantics with gcc 4.3, and "static inline" is correct here. Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Matthew Wilcox <willy@debian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2007-02-17[PARISC] add ASM_EXCEPTIONTABLE_ENTRY() macroHelge Deller1-28/+10
- this macro unifies the code to add exception table entries - additionally use ENTRY()/ENDPROC() at more places Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel1-1/+0
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-10-22[PARISC] Disable use of fpregs in pa_memcpyRandolph Chung1-0/+2
Disable use of fpregs in pa_memcpy, and turn on the -mdisable-fpregs flag. Signed-off-by: Randolph Chung <tausq@parisc-linux.org> Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2005-04-17Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+522
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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