- 06 1月, 2010 1 次提交
-
-
由 Heiko Carstens 提交于
Callers of copy_from_user() expect it to return the number of bytes it could not copy. In no case it is supposed to return -EFAULT. In case of a detected buffer overflow just return the requested length. In addition one could think of a memset that would clear the size of the target object. [ hpa: code is not in .32 so not needed for -stable ] Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com> Acked-by: NArjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20100105131911.GC5480@osiris.boeblingen.de.ibm.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
-
- 03 10月, 2009 1 次提交
-
-
由 Arjan van de Ven 提交于
For automated testing it is useful to have the option to turn the warnings on copy_from_user() etc checks into errors: In function ‘copy_from_user’, inlined from ‘fd_copyin’ at drivers/block/floppy.c:3080, inlined from ‘fd_ioctl’ at drivers/block/floppy.c:3503: linux/arch/x86/include/asm/uaccess_32.h:213: error: call to ‘copy_from_user_overflow’ declared with attribute error: copy_from_user buffer size is not provably correct Signed-off-by: NArjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20091002075050.4e9f7641@infradead.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 01 10月, 2009 1 次提交
-
-
由 Arjan van de Ven 提交于
A previous patch added the buffer size check to copy_from_user(). One of the things learned from analyzing the result of the previous patch is that in general, gcc is really good at proving that the code contains sufficient security checks to not need to do a runtime check. But that for those cases where gcc could not prove this, there was a relatively high percentage of real security issues. This patch turns the case of "gcc cannot prove" into a compile time warning, as long as a sufficiently new gcc is in use that supports this. The objective is that these warnings will trigger developers checking new cases out before a security hole enters a linux kernel release. Signed-off-by: NArjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Cc: Jan Beulich <jbeulich@novell.com> LKML-Reference: <20090930130523.348ae6c4@infradead.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 26 9月, 2009 1 次提交
-
-
由 Arjan van de Ven 提交于
gcc (4.x) supports the __builtin_object_size() builtin, which reports the size of an object that a pointer point to, when known at compile time. If the buffer size is not known at compile time, a constant -1 is returned. This patch uses this feature to add a sanity check to copy_from_user(); if the target buffer is known to be smaller than the copy size, the copy is aborted and a WARNing is emitted in memory debug mode. These extra checks compile away when the object size is not known, or if both the buffer size and the copy length are constants. Signed-off-by: NArjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20090926143301.2c396b94@infradead.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 21 9月, 2009 1 次提交
-
-
由 Sergey Senozhatsky 提交于
Trivial: correct "that the we don't" typo. Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com> LKML-Reference: <20090917125401.GU3717@localdomain.by> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 02 3月, 2009 1 次提交
-
-
由 Ingo Molnar 提交于
Impact: standardize IO on cached ops On modern CPUs it is almost always a bad idea to use non-temporal stores, as the regression in this commit has shown it: 30d697fa: x86: fix performance regression in write() syscall The kernel simply has no good information about whether using non-temporal stores is a good idea or not - and trying to add heuristics only increases complexity and inserts fragility. The regression on cached write()s took very long to be found - over two years. So dont take any chances and let the hardware decide how it makes use of its caches. The only exception is drivers/gpu/drm/i915/i915_gem.c: there were we are absolutely sure that another entity (the GPU) will pick up the dirty data immediately and that the CPU will not touch that data before the GPU will. Also, keep the _nocache() primitives to make it easier for people to experiment with these details. There may be more clear-cut cases where non-cached copies can be used, outside of filemap.c. Cc: Salman Qazi <sqazi@google.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 25 2月, 2009 1 次提交
-
-
由 Ingo Molnar 提交于
Impact: cleanup, enable future change Add a 'total bytes copied' parameter to __copy_from_user_*nocache(), and update all the callsites. The parameter is not used yet - architecture code can use it to more intelligently decide whether the copy should be cached or non-temporal. Cc: Salman Qazi <sqazi@google.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 23 10月, 2008 2 次提交
-
-
由 H. Peter Anvin 提交于
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
-
由 Al Viro 提交于
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk> Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
-
- 11 9月, 2008 1 次提交
-
-
由 Nick Piggin 提交于
- introduce might_fault() - handle the atomic user copy paths correctly [ mingo@elte.hu: move might_sleep() outside of in_atomic(). ] Signed-off-by: NNick Piggin <npiggin@suse.de> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 10 9月, 2008 1 次提交
-
-
由 Nick Piggin 提交于
copy_to/from_user and all its variants (except the atomic ones) can take a page fault and perform non-trivial work like taking mmap_sem and entering the filesyste/pagecache. Unfortunately, this often escapes lockdep because a common pattern is to use it to read in some arguments just set up from userspace, or write data back to a hot buffer. In those cases, it will be unlikely for page reclaim to get a window in to cause copy_*_user to fault. With the new might_lock primitives, add some annotations to x86. I don't know if I caught all possible faulting points (it's a bit of a maze, and I didn't really look at 32-bit). But this is a starting point. Boots and runs OK so far. Signed-off-by: NNick Piggin <npiggin@suse.de> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 23 7月, 2008 1 次提交
-
-
由 Vegard Nossum 提交于
This patch is the result of an automatic script that consolidates the format of all the headers in include/asm-x86/. The format: 1. No leading underscore. Names with leading underscores are reserved. 2. Pathname components are separated by two underscores. So we can distinguish between mm_types.h and mm/types.h. 3. Everything except letters and numbers are turned into single underscores. Signed-off-by: NVegard Nossum <vegard.nossum@gmail.com>
-
- 09 7月, 2008 16 次提交
-
-
由 Glauber Costa 提交于
Remove them from the arch-specific file. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
x86_64 does not need it, but it won't have X86_INTEL_USERCOPY defined either. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
We also carry the unaligned version with us. Only x86_64 uses it, but there's no problem in defining it. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Move both versions, which are highly similar, to uaccess.h. Note that, for x86_64, X86_WP_WORKS_OK is always defined. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
For both __put_user_x and __put_user_8 macros, pass the error variable explicitly. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Move __get_user_asm and __get_user_size and __get_user_nocheck to uaccess.h. This requires us to define a macro at __get_user_size for the 64-bit access case. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Move both __put_user_asm and __put_user_size to uaccess.h. i386 already had a special function for 64-bit access, so for x86_64, we just define a macro with the same name. Note that for X86_64, CONFIG_X86_WP_WORKS_OK will always be defined, so the #else part will never be even compiled in. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Do it in a separate patch for bisectability. Goal is to have put_user_size integrated. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Take it out of uaccess_32.h. Since it seems that no users of the x86_64 exists, we simply pick the i386 version. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Merge versions of getuser from uaccess_32.h and uaccess_64.h into uaccess.h. There is a part which is 64-bit only (for now), and for that, we use a __get_user_8 macro. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Common parts of uaccess_32.h and uaccess_64.h are put in uaccess.h. Bits in uaccess_32.h and uaccess_64.h that come to this file are equal except for comments and whitespaces differences. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Using explicit hexa (0xFFFFFFUL) introduces an unnecessary difference between i386 and x86_64 because of the size of their long. Use -1UL instead. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Do not refer to the processor word-size with int, as it won't work with x86_64. Use long instead. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
For i386, __range_not_ok is a better name than __range_ok, since it returns 0 when it is in fact okay. Other than that, both versions does not need the word size specifiers, and we remove them. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Follow the pattern, and define a single put_user_x, instead of defining macros for all available sizes. Exception is put_user_8, since the "A" constraint does not give us enough power to specify which register (a or d) to use in the 32-bit common case. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Glauber Costa 提交于
Clobber it in the inline asm macros, and let the compiler do this for us. Signed-off-by: NGlauber Costa <gcosta@redhat.com> Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 17 4月, 2008 1 次提交
-
-
由 Joe Perches 提交于
Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 04 2月, 2008 1 次提交
-
-
由 H. Peter Anvin 提交于
Use the _ASM_EXTABLE macro from <asm/asm.h>, instead of open-coding __ex_table entires in include/asm-x86/uaccess_32.h. Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Signed-off-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 11 10月, 2007 1 次提交
-
-
由 Thomas Gleixner 提交于
Move the headers to include/asm-x86 and fixup the header install make rules Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 22 7月, 2007 1 次提交
-
-
由 Robert P. J. Day 提交于
Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NAndi Kleen <ak@suse.de> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 03 5月, 2007 1 次提交
-
-
由 Aneesh Kumar K.V 提交于
Explicity specify that the caller should pin the user memory otherwise the function will sleep Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@gmail.com> Signed-off-by: NAndi Kleen <ak@suse.de>
-
- 12 2月, 2007 1 次提交
-
-
由 Tilman Schmidt 提交于
Rename the variable "sum" in the __range_ok macros to avoid name collisions causing lots of "symbol shadows an earlier one" warnings by sparse. Signed-off-by: NTilman Schmidt <tilman@imap.cc> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Andi Kleen <ak@suse.de> Cc: Hirokazu Takata <takata@linux-m32r.org> Acked-by: NIan Molton <spyro@f2s.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 12 10月, 2006 1 次提交
-
-
由 Randy Dunlap 提交于
Place kernel-doc function comment header immediately before the function that is being documented. Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
-
- 26 6月, 2006 2 次提交
-
-
由 NeilBrown 提交于
As described in a previous patch and documented in mm/filemap.h, copy_from_user_inatomic* shouldn't zero out the tail of the buffer after an incomplete copy. This patch implements that change for i386. For the _nocache version, a new __copy_user_intel_nocache is defined similar to copy_user_zeroio_intel_nocache, and this is ultimately used for the copy. For the regular version, __copy_from_user_ll_nozero is defined which uses __copy_user and __copy_user_intel - the later needs casts to reposition the __user annotations. If copy_from_user_atomic is given a constant length of 1, 2, or 4, then we do still zero the destintion on failure. This didn't seem worth the effort of fixing as the places where it is used really don't care. Signed-off-by: NNeil Brown <neilb@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
-
由 NeilBrown 提交于
The problem is that when we write to a file, the copy from userspace to pagecache is first done with preemption disabled, so if the source address is not immediately available the copy fails *and* *zeros* *the* *destination*. This is a problem because a concurrent read (which admittedly is an odd thing to do) might see zeros rather that was there before the write, or what was there after, or some mixture of the two (any of these being a reasonable thing to see). If the copy did fail, it will immediately be retried with preemption re-enabled so any transient problem with accessing the source won't cause an error. The first copying does not need to zero any uncopied bytes, and doing so causes the problem. It uses copy_from_user_atomic rather than copy_from_user so the simple expedient is to change copy_from_user_atomic to *not* zero out bytes on failure. The first of these two patches prepares for the change by fixing two places which assume copy_from_user_atomic does zero the tail. The two usages are very similar pieces of code which copy from a userspace iovec into one or more page-cache pages. These are changed to remove the assumption. The second patch changes __copy_from_user_inatomic* to not zero the tail. Once these are accepted, I will look at similar patches of other architectures where this is important (ppc, mips and sparc being the ones I can find). This patch: There is a problem with __copy_from_user_inatomic zeroing the tail of the buffer in the case of an error. As it is called in atomic context, the error may be transient, so it results in zeros being written where maybe they shouldn't be. In the usage in filemap, this opens a window for a well timed read to see data (zeros) which is not consistent with any ordering of reads and writes. Most cases where __copy_from_user_inatomic is called, a failure results in __copy_from_user being called immediately. As long as the latter zeros the tail, the former doesn't need to. However in *copy_from_user_iovec implementations (in both filemap and ntfs/file), it is assumed that copy_from_user_inatomic will zero the tail. This patch removes that assumption, so that after this patch it will be safe for copy_from_user_inatomic to not zero the tail. This patch also adds some commentary to filemap.h and asm-i386/uaccess.h. After this patch, all architectures that might disable preempt when kmap_atomic is called need to have their __copy_from_user_inatomic* "fixed". This includes - powerpc - i386 - mips - sparc Signed-off-by: NNeil Brown <neilb@suse.de> Cc: David Howells <dhowells@redhat.com> Cc: Anton Altaparmakov <aia21@cantab.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: William Lee Irwin III <wli@holomorphy.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
-
- 23 6月, 2006 2 次提交
-
-
由 Roman Zippel 提交于
An immediate operand can't be the destination of the cmpl instruction, so exclude it. Signed-off-by: NRoman Zippel <zippel@linux-m68k.org> Cc: Mattia Dongili <malattia@linux.it> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
-
由 Hiro Yoshioka 提交于
Use the x86 cache-bypassing copy instructions for copy_from_user(). Some performance data are Total of GLOBAL_POWER_EVENTS (CPU cycle samples) 2.6.12.4.orig 1921587 2.6.12.4.nt 1599424 1599424/1921587=83.23% (16.77% reduction) BSQ_CACHE_REFERENCE (L3 cache miss) 2.6.12.4.orig 57427 2.6.12.4.nt 20858 20858/57427=36.32% (63.7% reduction) L3 cache miss reduction of __copy_from_user_ll samples % 37408 65.1412 vmlinux __copy_from_user_ll 23 0.1103 vmlinux __copy_user_zeroing_intel_nocache 23/37408=0.061% (99.94% reduction) Top 5 of 2.6.12.4.nt Counted GLOBAL_POWER_EVENTS events (time during which processor is not stopped) with a unit mask of 0x01 (mandatory) count 100000 samples % app name symbol name 128392 8.0274 vmlinux __copy_user_zeroing_intel_nocache 64206 4.0143 vmlinux journal_add_journal_head 59746 3.7355 vmlinux do_get_write_access 47674 2.9807 vmlinux journal_put_journal_head 46021 2.8774 vmlinux journal_dirty_metadata pattern9-0-cpu4-0-09011728/summary.out Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x3f (multiple flags) count 3000 samples % app name symbol name 69755 4.2861 vmlinux __copy_user_zeroing_intel_nocache 55685 3.4215 vmlinux journal_add_journal_head 52371 3.2179 vmlinux __find_get_block 45504 2.7960 vmlinux journal_put_journal_head 36005 2.2123 vmlinux journal_stop pattern9-0-cpu4-0-09011744/summary.out Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x200 (read 3rd level cache miss) count 3000 samples % app name symbol name 1147 5.4994 vmlinux journal_add_journal_head 881 4.2240 vmlinux journal_dirty_data 872 4.1809 vmlinux blk_rq_map_sg 734 3.5192 vmlinux journal_commit_transaction 617 2.9582 vmlinux radix_tree_delete pattern9-0-cpu4-0-09011731/summary.out iozone results are original 2.6.12.4 CPU time = 207.768 sec cache aware CPU time = 184.783 sec (three times run) 184.783/207.768=88.94% (11.06% reduction) original: pattern9-0-cpu4-0-08191720/iozone.out: CPU Utilization: Wall time 45.997 CPU time 64.527 CPU utilization 140.28 % pattern9-0-cpu4-0-08191741/iozone.out: CPU Utilization: Wall time 46.878 CPU time 71.933 CPU utilization 153.45 % pattern9-0-cpu4-0-08191743/iozone.out: CPU Utilization: Wall time 45.152 CPU time 71.308 CPU utilization 157.93 % cache awre: pattern9-0-cpu4-0-09011728/iozone.out: CPU Utilization: Wall time 44.842 CPU time 62.465 CPU utilization 139.30 % pattern9-0-cpu4-0-09011731/iozone.out: CPU Utilization: Wall time 44.718 CPU time 59.273 CPU utilization 132.55 % pattern9-0-cpu4-0-09011744/iozone.out: CPU Utilization: Wall time 44.367 CPU time 63.045 CPU utilization 142.10 % Signed-off-by: NHiro Yoshioka <hyoshiok@miraclelinux.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
-
- 26 4月, 2006 1 次提交
-
-
由 David Woodhouse 提交于
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
-