18 Jun, 2020
1 commit
-
Better describe what these functions do.
Suggested-by: Linus Torvalds
Signed-off-by: Christoph Hellwig
Signed-off-by: Linus Torvalds
04 Feb, 2020
1 commit
-
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.Conversion rule is:
llseek => proc_lseek
unlocked_ioctl => proc_ioctlxxx => proc_xxx
delete ".owner = THIS_MODULE" line
[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan
Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
20 Aug, 2019
2 commits
-
Print the content of current->comm in messages generated by lockdown to
indicate a restriction that was hit. This makes it a bit easier to find
out what caused the message.The message now patterned something like:
Lockdown: : is restricted; see man kernel_lockdown.7
Signed-off-by: David Howells
Signed-off-by: Matthew Garrett
Reviewed-by: Kees Cook
Signed-off-by: James Morris -
Disallow access to /proc/kcore when the kernel is locked down to prevent
access to cryptographic data. This is limited to lockdown
confidentiality mode and is still permitted in integrity mode.Signed-off-by: David Howells
Signed-off-by: Matthew Garrett
Reviewed-by: Kees Cook
Signed-off-by: James Morris
30 Mar, 2019
1 commit
-
Fix sparse warning:
fs/proc/kcore.c:591:19: warning:
symbol 'kcore_modules' was not declared. Should it be static?Link: http://lkml.kernel.org/r/20190320135417.13272-1-yuehaibing@huawei.com
Signed-off-by: YueHaibing
Acked-by: Mukesh Ojha
Cc: Alexey Dobriyan
Cc: Omar Sandoval
Cc: James Morse
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
23 Mar, 2019
1 commit
-
On machines where the GART aperture is mapped over physical RAM,
/proc/kcore contains the GART aperture range. Accessing the GART range via
/proc/kcore results in a kernel crash.vmcore used to have the same issue, until it was fixed with commit
2a3e83c6f96c ("x86/gart: Exclude GART aperture from vmcore")', leveraging
existing hook infrastructure in vmcore to let /proc/vmcore return zeroes
when attempting to read the aperture region, and so it won't read from the
actual memory.Apply the same workaround for kcore. First implement the same hook
infrastructure for kcore, then reuse the hook functions introduced in the
previous vmcore fix. Just with some minor adjustment, rename some functions
for more general usage, and simplify the hook infrastructure a bit as there
is no module usage yet.Suggested-by: Baoquan He
Signed-off-by: Kairui Song
Signed-off-by: Thomas Gleixner
Reviewed-by: Jiri Bohac
Acked-by: Baoquan He
Cc: Borislav Petkov
Cc: "H. Peter Anvin"
Cc: Alexey Dobriyan
Cc: Andrew Morton
Cc: Omar Sandoval
Cc: Dave Young
Link: https://lkml.kernel.org/r/20190308030508.13548-1-kasong@redhat.com
31 Oct, 2018
1 commit
-
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include@@
@@
- #include
+ #include[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport
Signed-off-by: Stephen Rothwell
Acked-by: Michal Hocko
Cc: Catalin Marinas
Cc: Chris Zankel
Cc: "David S. Miller"
Cc: Geert Uytterhoeven
Cc: Greentime Hu
Cc: Greg Kroah-Hartman
Cc: Guan Xuetao
Cc: Ingo Molnar
Cc: "James E.J. Bottomley"
Cc: Jonas Bonn
Cc: Jonathan Corbet
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Martin Schwidefsky
Cc: Matt Turner
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Burton
Cc: Richard Kuo
Cc: Richard Weinberger
Cc: Rich Felker
Cc: Russell King
Cc: Serge Semin
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vineet Gupta
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
21 Sep, 2018
1 commit
-
The 'm' kcore_list item could point to kclist_head, and it is incorrect to
look at m->addr / m->size in this case.There is no choice but to run through the list of entries for every
address if we did not find any entry in the previous iterationReset 'm' to NULL in that case at Omar Sandoval's suggestion.
[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/1536100702-28706-1-git-send-email-asmadeus@codewreck.org
Fixes: bf991c2231117 ("proc/kcore: optimize multiple page reads")
Signed-off-by: Dominique Martinet
Reviewed-by: Andrew Morton
Cc: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Eric Biederman
Cc: James Morse
Cc: Bhupesh Sharma
Signed-off-by: Andrew Morton
Signed-off-by: Greg Kroah-Hartman
27 Aug, 2018
1 commit
-
Pull perf updates from Thomas Gleixner:
"Kernel:
- Improve kallsyms coverage
- Add x86 entry trampolines to kcore
- Fix ARM SPE handling
- Correct PPC event post processingTools:
- Make the build system more robust
- Small fixes and enhancements all over the place
- Update kernel ABI header copies
- Preparatory work for converting libtraceevnt to a shared library
- License cleanups"* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy'
tools arch x86: Update tools's copy of cpufeatures.h
perf python: Fix pyrf_evlist__read_on_cpu() interface
perf mmap: Store real cpu number in 'struct perf_mmap'
perf tools: Remove ext from struct kmod_path
perf tools: Add gzip_is_compressed function
perf tools: Add lzma_is_compressed function
perf tools: Add is_compressed callback to compressions array
perf tools: Move the temp file processing into decompress_kmodule
perf tools: Use compression id in decompress_kmodule()
perf tools: Store compression id into struct dso
perf tools: Add compression id into 'struct kmod_path'
perf tools: Make is_supported_compression() static
perf tools: Make decompress_to_file() function static
perf tools: Get rid of dso__needs_decompress() call in __open_dso()
perf tools: Get rid of dso__needs_decompress() call in symbol__disassemble()
perf tools: Get rid of dso__needs_decompress() call in read_object_code()
tools lib traceevent: Change to SPDX License format
perf llvm: Allow passing options to llc in addition to clang
perf parser: Improve error message for PMU address filters
...
23 Aug, 2018
9 commits
-
The vmcoreinfo information is useful for runtime debugging tools, not just
for crash dumps. A lot of this information can be determined by other
means, but this is much more convenient, and it only adds a page at most
to the file.Link: http://lkml.kernel.org/r/fddbcd08eed76344863303878b12de1c1e2a04b6.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The current code does a full search of the segment list every time for
every page. This is wasteful, since it's almost certain that the next
page will be in the same segment. Instead, check if the previous segment
covers the current page before doing the list search.Link: http://lkml.kernel.org/r/fd346c11090cf93d867e01b8d73a6567c5ac6361.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently, the ELF file header, program headers, and note segment are
allocated all at once, in some icky code dating back to 2.3. Programs
tend to read the file header, then the program headers, then the note
segment, all separately, so this is a waste of effort. It's cleaner and
more efficient to handle the three separately.Link: http://lkml.kernel.org/r/19c92cbad0e11f6103ff3274b2e7a7e51a1eb74b.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Now that we're using an rwsem, we can hold it during the entirety of
read_kcore() and have a common return path. This is preparation for the
next change.[akpm@linux-foundation.org: fix locking bug reported by Tetsuo Handa]
Link: http://lkml.kernel.org/r/d7cfbc1e8a76616f3b699eaff9df0a2730380534.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Cc: Tetsuo Handa
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There's a theoretical race condition that will cause /proc/kcore to miss
a memory hotplug event:CPU0 CPU1
// hotplug event 1
kcore_need_update = 1open_kcore() open_kcore()
kcore_update_ram() kcore_update_ram()
// Walk RAM // Walk RAM
__kcore_update_ram() __kcore_update_ram()
kcore_need_update = 0// hotplug event 2
kcore_need_update = 1
kcore_need_update = 0Note that CPU1 set up the RAM kcore entries with the state after hotplug
event 1 but cleared the flag for hotplug event 2. The RAM entries will
therefore be stale until there is another hotplug event.This is an extremely unlikely sequence of events, but the fix makes the
synchronization saner, anyways: we serialize the entire update sequence,
which means that whoever clears the flag will always succeed in replacing
the kcore list.Link: http://lkml.kernel.org/r/6106c509998779730c12400c1b996425df7d7089.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Now we only need kclist_lock from user context and at fs init time, and
the following changes need to sleep while holding the kclist_lock.Link: http://lkml.kernel.org/r/521ba449ebe921d905177410fee9222d07882f0d.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Reviewed-by: Andrew Morton
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The memory hotplug notifier kcore_callback() only needs kclist_lock to
prevent races with __kcore_update_ram(), but we can easily eliminate that
race by using an atomic xchg() in __kcore_update_ram(). This is
preparation for converting kclist_lock to an rwsem.Link: http://lkml.kernel.org/r/0a4bc89f4dbde8b5b2ea309f7b4fb6a85fe29df2.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Reviewed-by: Andrew Morton
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Patch series "/proc/kcore improvements", v4.
This series makes a few improvements to /proc/kcore. It fixes a couple of
small issues in v3 but is otherwise the same. Patches 1, 2, and 3 are
prep patches. Patch 4 is a fix/cleanup. Patch 5 is another prep patch.
Patches 6 and 7 are optimizations to ->read(). Patch 8 makes it possible
to enable CRASH_CORE on any architecture, which is needed for patch 9.
Patch 9 adds vmcoreinfo to /proc/kcore.This patch (of 9):
kclist_add() is only called at init time, so there's no point in grabbing
any locks. We're also going to replace the rwlock with a rwsem, which we
don't want to try grabbing during early boot.While we're here, mark kclist_add() with __init so that we'll get a
warning if it's called from non-init code.Link: http://lkml.kernel.org/r/98208db1faf167aa8b08eebfa968d95c70527739.1531953780.git.osandov@fb.com
Signed-off-by: Omar Sandoval
Reviewed-by: Andrew Morton
Reviewed-by: Bhupesh Sharma
Tested-by: Bhupesh Sharma
Cc: Alexey Dobriyan
Cc: Bhupesh Sharma
Cc: Eric Biederman
Cc: James Morse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
elf_kcore_store_hdr() uses __pa() to find the physical address of
KCORE_RAM or KCORE_TEXT entries exported as program headers.This trips CONFIG_DEBUG_VIRTUAL's checks, as the KCORE_TEXT entries are
not in the linear map.Handle these two cases separately, using __pa_symbol() for the KCORE_TEXT
entries.Link: http://lkml.kernel.org/r/20180711131944.15252-1-james.morse@arm.com
Signed-off-by: James Morse
Cc: Alexey Dobriyan
Cc: Omar Sandoval
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Aug, 2018
1 commit
-
Without program headers for PTI entry trampoline pages, the trampoline
virtual addresses do not map to anything.Example before:
sudo gdb --quiet vmlinux /proc/kcore
Reading symbols from vmlinux...done.
[New process 1]
Core was generated by `BOOT_IMAGE=/boot/vmlinuz-4.16.0 root=UUID=a6096b83-b763-4101-807e-f33daff63233'.
#0 0x0000000000000000 in irq_stack_union ()
(gdb) x /21ib 0xfffffe0000006000
0xfffffe0000006000: Cannot access memory at address 0xfffffe0000006000
(gdb) quitAfter:
sudo gdb --quiet vmlinux /proc/kcore
[sudo] password for ahunter:
Reading symbols from vmlinux...done.
[New process 1]
Core was generated by `BOOT_IMAGE=/boot/vmlinuz-4.16.0-fix-4-00005-gd6e65a8b4072 root=UUID=a6096b83-b7'.
#0 0x0000000000000000 in irq_stack_union ()
(gdb) x /21ib 0xfffffe0000006000
0xfffffe0000006000: swapgs
0xfffffe0000006003: mov %rsp,-0x3e12(%rip) # 0xfffffe00000021f8
0xfffffe000000600a: xchg %ax,%ax
0xfffffe000000600c: mov %cr3,%rsp
0xfffffe000000600f: bts $0x3f,%rsp
0xfffffe0000006014: and $0xffffffffffffe7ff,%rsp
0xfffffe000000601b: mov %rsp,%cr3
0xfffffe000000601e: mov -0x3019(%rip),%rsp # 0xfffffe000000300c
0xfffffe0000006025: pushq $0x2b
0xfffffe0000006027: pushq -0x3e35(%rip) # 0xfffffe00000021f8
0xfffffe000000602d: push %r11
0xfffffe000000602f: pushq $0x33
0xfffffe0000006031: push %rcx
0xfffffe0000006032: push %rdi
0xfffffe0000006033: mov $0xffffffff91a00010,%rdi
0xfffffe000000603a: callq 0xfffffe0000006046
0xfffffe000000603f: pause
0xfffffe0000006041: lfence
0xfffffe0000006044: jmp 0xfffffe000000603f
0xfffffe0000006046: mov %rdi,(%rsp)
0xfffffe000000604a: retq
(gdb) quitIn addition, entry trampolines all map to the same page. Represent that
by giving the corresponding program headers in kcore the same offset.This has the benefit that, when perf tools uses /proc/kcore as a source
for kernel object code, samples from different CPU trampolines are
aggregated together. Note, such aggregation is normal for profiling
i.e. people want to profile the object code, not every different virtual
address the object code might be mapped to (across different processes
for example).Notes by PeterZ:
This also adds the KCORE_REMAP functionality.
Signed-off-by: Adrian Hunter
Acked-by: Andi Kleen
Acked-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Andy Lutomirski
Cc: Dave Hansen
Cc: H. Peter Anvin
Cc: Jiri Olsa
Cc: Joerg Roedel
Cc: Thomas Gleixner
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1528289651-4113-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo
12 May, 2018
1 commit
-
The existing kcore code checks for bad addresses against __va(0) with
the assumption that this is the lowest address on the system. This may
not hold true on some systems (e.g. arm64) and produce overflows and
crashes. Switch to using other functions to validate the address range.It's currently only seen on arm64 and it's not clear if anyone wants to
use that particular combination on a stable release. So this is not
urgent for stable.Link: http://lkml.kernel.org/r/20180501201143.15121-1-labbott@redhat.com
Signed-off-by: Laura Abbott
Tested-by: Dave Anderson
Cc: Kees Cook
Cc: Ard Biesheuvel
Cc: Ingo Molnar
Cc: Andi Kleen
Cc: Alexey Dobriyan a
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Feb, 2018
1 commit
-
Commit:
df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data")
... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y.
However, accessing the vsyscall user page will cause an SMAP fault.Replace memcpy() with copy_from_user() to fix this bug works, but adding
a common way to handle this sort of user page may be useful for future.Currently, only vsyscall page requires KCORE_USER.
Signed-off-by: Jia Zhang
Reviewed-by: Jiri Olsa
Cc: Al Viro
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar
07 Feb, 2018
1 commit
-
Commit df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext
data") added a bounce buffer to avoid hardened usercopy checks. Copying
to the bounce buffer was implemented with a simple memcpy() assuming
that it is always valid to read from kernel memory iff the
kern_addr_valid() check passed.A simple, but pointless, test case like "dd if=/proc/kcore of=/dev/null"
now can easily crash the kernel, since the former execption handling on
invalid kernel addresses now doesn't work anymore.Also adding a kern_addr_valid() implementation wouldn't help here. Most
architectures simply return 1 here, while a couple implemented a page
table walk to figure out if something is mapped at the address in
question.With DEBUG_PAGEALLOC active mappings are established and removed all the
time, so that relying on the result of kern_addr_valid() before
executing the memcpy() also doesn't work.Therefore simply use probe_kernel_read() to copy to the bounce buffer.
This also allows to simplify read_kcore().At least on s390 this fixes the observed crashes and doesn't introduce
warnings that were removed with df04abfd181a ("fs/proc/kcore.c: Add
bounce buffer for ktext data"), even though the generic
probe_kernel_read() implementation uses uaccess functions.While looking into this I'm also wondering if kern_addr_valid() could be
completely removed...(?)Link: http://lkml.kernel.org/r/20171202132739.99971-1-heiko.carstens@de.ibm.com
Fixes: df04abfd181a ("fs/proc/kcore.c: Add bounce buffer for ktext data")
Fixes: f5509cc18daa ("mm: Hardened usercopy")
Signed-off-by: Heiko Carstens
Acked-by: Kees Cook
Cc: Jiri Olsa
Cc: Al Viro
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 Nov, 2017
1 commit
-
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.By default all files without license information are under the default
license of the kernel, which is GPL version 2.Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if
Reviewed-by: Philippe Ombredanne
Reviewed-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
20 Jun, 2017
1 commit
-
Instead of passing each start address into is_vmalloc_or_module_addr()
to decide whether it falls into either the VMALLOC or the MODULES region,
we can simply check the type field of the current kcore_list entry, since
it will be set to KCORE_VMALLOC based on exactly the same conditions.As a bonus, when reading the KCORE_TEXT region on architectures that have
one, this will avoid using vread() on the region if it happens to intersect
with a KCORE_VMALLOC region. This is due the fact that the KCORE_TEXT
region is the first one to be added to the kcore region list.Reported-by: Tan Xiaojun
Tested-by: Tan Xiaojun
Tested-by: Mark Rutland
Acked-by: Mark Rutland
Reviewed-by: Laura Abbott
Reviewed-by: Jiri Olsa
Signed-off-by: Ard Biesheuvel
Signed-off-by: Will Deacon
02 Mar, 2017
1 commit
-
We are going to split out of , which
will have to be picked up from other headers and a couple of .c files.Create a trivial placeholder file that just
maps to to make this patch obviously correct and
bisectable.Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds
Cc: Mike Galbraith
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
28 Feb, 2017
1 commit
-
Currently all the p_paddr of PT_LOAD headers are assigned to 0, which is
not true and could be misleading, since 0 is a valid physical address.User space tools like makedumpfile needs to know physical address for
PT_LOAD segments of direct mapped regions. Therefore this patch updates
paddr for such regions. It also sets an invalid paddr (-1) for other
regions, so that user space tool can know whether a physical address
provided in PT_LOAD is correct or not.I do not know why it was 0, which is a valid physical address. But
certainly, it might break some user space tools, and those need to be
fixed. For example, see following code from kexec-toolskexec/kexec-elf.c:build_mem_phdrs()
if ((phdr->p_paddr + phdr->p_memsz) < phdr->p_paddr) {
/* The memory address wraps */
if (probe_debug) {
fprintf(stderr, "ELF address wrap around\n");
}
return -1;
}We do not need to perform above check for an invalid physical address.
I think, kexec-tools and makedumpfile will need fixup. I already have
those fixup which will be sent upstream once this patch makes through.
Pro with this approach is that, it will help to calculate variable like
page_offset, phys_base from PT_LOAD even when they are randomized and
therefore will reduce many variable and version specific values in user
space tools.Having an ASLR offset information can help to translate an identity
mapped virtual address to a physical address. But that would be an
additional field in PT_LOAD header structure and an arch dependent
value.Moreover, sending a valid physical address like 0 does not seem right.
So, IMHO it is better to fix that and send valid physical address when
available (identity mapped).Link: http://lkml.kernel.org/r/f951340d2917cdd2a329fae9837a83f2059dc3b2.1485318868.git.panand@redhat.com
Signed-off-by: Pratyush Anand
Cc: Baoquan He
Cc: Dave Young
Cc: Dave Anderson
Cc: Atsushi Kumagai
Cc: Simon Horman
Cc: Kees Cook
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Dec, 2016
1 commit
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This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
sed -i -e "s!$PATT!#include !" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)to do the replacement at the end of the merge window.
Requested-by: Al Viro
Signed-off-by: Linus Torvalds
21 Sep, 2016
2 commits
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We hit hardened usercopy feature check for kernel text access by reading
kcore file:usercopy: kernel memory exposure attempt detected from ffffffff8179a01f () (4065 bytes)
kernel BUG at mm/usercopy.c:75!Bypassing this check for kcore by adding bounce buffer for ktext data.
Reported-by: Steve Best
Fixes: f5509cc18daa ("mm: Hardened usercopy")
Suggested-by: Kees Cook
Signed-off-by: Jiri Olsa
Acked-by: Kees Cook
Signed-off-by: Linus Torvalds -
Next patch adds bounce buffer for ktext area, so it's
convenient to have single bounce buffer for both
vmalloc/module and ktext cases.Suggested-by: Linus Torvalds
Signed-off-by: Jiri Olsa
Acked-by: Kees Cook
Signed-off-by: Linus Torvalds
23 Jan, 2016
1 commit
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parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.Signed-off-by: Al Viro
18 Jul, 2015
2 commits
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Don't burden architectures without dynamic task_struct sizing
with the overhead of dynamic sizing.Also optimize the x86 code a bit by caching task_struct_size.
Acked-and-Tested-by: Dave Hansen
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Dave Hansen
Cc: Denys Vlasenko
Cc: Linus Torvalds
Cc: Oleg Nesterov
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/1437128892-9831-3-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar -
The FPU rewrite removed the dynamic allocations of 'struct fpu'.
But, this potentially wastes massive amounts of memory (2k per
task on systems that do not have AVX-512 for instance).Instead of having a separate slab, this patch just appends the
space that we need to the 'task_struct' which we dynamically
allocate already. This saves from doing an extra slab
allocation at fork().The only real downside here is that we have to stick everything
and the end of the task_struct. But, I think the
BUILD_BUG_ON()s I stuck in there should keep that from being too
fragile.Signed-off-by: Dave Hansen
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Dave Hansen
Cc: Denys Vlasenko
Cc: H. Peter Anvin
Cc: Linus Torvalds
Cc: Oleg Nesterov
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/1437128892-9831-2-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar
10 Oct, 2014
1 commit
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On some ARCHs modules range is eauql to vmalloc range. E.g on i686
"#define MODULES_VADDR VMALLOC_START"
"#define MODULES_END VMALLOC_END"This will cause 2 duplicate program segments in /proc/kcore, and no flag
to indicate they are different. This is confusing. And usually people
who need check the elf header or read the content of kcore will check
memory ranges. Two program segments which are the same are unnecessary.So check if the modules range is equal to vmalloc range. If so, just skip
adding the modules range.[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Baoquan He
Cc: Xishi Qiu
Cc: Paul Gortmaker
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Aug, 2014
1 commit
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Use mm.h definition.
Signed-off-by: Fabian Frederick
Cc: Xishi Qiu
Acked-by: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 Jan, 2014
1 commit
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PROC_FS is a bool, so this code is either present or absent. It will
never be modular, so using module_init as an alias for __initcall is
rather misleading.Fix this up now, so that we can relocate module_init from init.h into
module.h in the future. If we don't do this, we'd have to add module.h to
obviously non-modular code, and that would be ugly at best.Note that direct use of __initcall is discouraged, vs. one of the
priority categorized subgroups. As __initcall gets mapped onto
device_initcall, our use of fs_initcall (which makes sense for fs code)
will thus change these registrations from level 6-device to level 5-fs
(i.e. slightly earlier). However no observable impact of that small
difference has been observed during testing, or is expected.Also note that this change uncovers a missing semicolon bug in the
registration of vmcore_init as an initcall.Signed-off-by: Paul Gortmaker
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Nov, 2013
1 commit
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Use "pgdat_end_pfn()" instead of "pgdat->node_start_pfn +
pgdat->node_spanned_pages". Simplify the code, no functional change.Signed-off-by: Xishi Qiu
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Jul, 2013
1 commit
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For NUL terminated string, set '\0' at the end.
Signed-off-by: Zhao Hongjiang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 May, 2013
2 commits
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Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
... -
Move non-public declarations and definitions from linux/proc_fs.h to
fs/proc/internal.h.Signed-off-by: David Howells
Signed-off-by: Al Viro
30 Apr, 2013
1 commit
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Saves an ifdef, no code size changes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
