alloc_tag: allocate percpu counters for module tags dynamically

When a module gets unloaded it checks whether any of its tags are still in
use and if so, we keep the memory containing module's alloc

alloc_tag: allocate percpu counters for module tags dynamically

When a module gets unloaded it checks whether any of its tags are still in
use and if so, we keep the memory containing module's allocation tags
alive until all tags are unused. However percpu counters referenced by
the tags are freed by free_module(). This will lead to UAF if the memory
allocated by a module is accessed after module was unloaded.

To fix this we allocate percpu counters for module allocation tags
dynamically and we keep it alive for tags which are still in use after
module unloading. This also removes the requirement of a larger
PERCPU_MODULE_RESERVE when memory allocation profiling is enabled because
percpu memory for counters does not need to be reserved anymore.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 0db6f8d7820a ("alloc_tag: load module tags into separate contiguous memory")
Signed-off-by: Suren Baghdasaryan <[email protected]>
Reported-by: David Wang <[email protected]>
Closes: https://lore.kernel.org/all/[email protected]/
Tested-by: David Wang <[email protected]>
Cc: Christoph Lameter (Ampere) <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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alloc_tag: support for page allocation tag compression

Implement support for storing page allocation tag references directly in
the page flags instead of page extensions. sysctl.vm.mem_profiling bo

alloc_tag: support for page allocation tag compression

Implement support for storing page allocation tag references directly in
the page flags instead of page extensions. sysctl.vm.mem_profiling boot
parameter it extended to provide a way for a user to request this mode.
Enabling compression eliminates memory overhead caused by page_ext and
results in better performance for page allocations. However this mode
will not work if the number of available page flag bits is insufficient to
address all kernel allocations. Such condition can happen during boot or
when loading a module. If this condition is detected, memory allocation
profiling gets disabled with an appropriate warning. By default
compression mode is disabled.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Reviewed-by: Pasha Tatashin <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov (AMD) <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Daniel Gomez <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Kalesh Singh <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Petr Pavlu <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Sourav Panda <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Thomas Huth <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Xiongwei Song <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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alloc_tag: load module tags into separate contiguous memory

When a module gets unloaded there is a possibility that some of the
allocations it made are still used and therefore the allocation tags
c

alloc_tag: load module tags into separate contiguous memory

When a module gets unloaded there is a possibility that some of the
allocations it made are still used and therefore the allocation tags
corresponding to these allocations are still referenced. As such, the
memory for these tags can't be freed. This is currently handled as an
abnormal situation and module's data section is not being unloaded. To
handle this situation without keeping module's data in memory, allow
codetags with longer lifespan than the module to be loaded into their own
separate memory. The in-use memory areas and gaps after module unloading
in this separate memory are tracked using maple trees. Allocation tags
arrange their separate memory so that it is virtually contiguous and that
will allow simple allocation tag indexing later on in this patchset. The
size of this virtually contiguous memory is set to store up to 100000
allocation tags.

[[email protected]: fix empty codetag module section handling]
Link: https://lkml.kernel.org/r/[email protected]
[[email protected]: update comment, per Dan]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Reviewed-by: Pasha Tatashin <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov (AMD) <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Daniel Gomez <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Kalesh Singh <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Petr Pavlu <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Sourav Panda <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Thomas Huth <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Xiongwei Song <[email protected]>
Cc: Yu Zhao <[email protected]>
Cc: Dan Carpenter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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lib: add memory allocations report in show_mem()

Include allocations in show_mem reports.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kent Overstreet

lib: add memory allocations report in show_mem()

Include allocations in show_mem reports.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kent Overstreet <[email protected]>
Signed-off-by: Suren Baghdasaryan <[email protected]>
Reviewed-by: Vlastimil Babka <[email protected]>
Tested-by: Kees Cook <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alex Gaynor <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Andreas Hindborg <[email protected]>
Cc: Benno Lossin <[email protected]>
Cc: "Björn Roy Baron" <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Gary Guo <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Wedson Almeida Filho <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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lib: prevent module unloading if memory is not freed

Skip freeing module's data section if there are non-zero allocation tags
because otherwise, once these allocations are freed, the access to their

lib: prevent module unloading if memory is not freed

Skip freeing module's data section if there are non-zero allocation tags
because otherwise, once these allocations are freed, the access to their
code tag would cause UAF.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Tested-by: Kees Cook <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alex Gaynor <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Andreas Hindborg <[email protected]>
Cc: Benno Lossin <[email protected]>
Cc: "Björn Roy Baron" <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Gary Guo <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Wedson Almeida Filho <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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lib: code tagging module support

Add support for code tagging from dynamically loaded modules.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghd

lib: code tagging module support

Add support for code tagging from dynamically loaded modules.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Suren Baghdasaryan <[email protected]>
Co-developed-by: Kent Overstreet <[email protected]>
Signed-off-by: Kent Overstreet <[email protected]>
Tested-by: Kees Cook <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alex Gaynor <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Andreas Hindborg <[email protected]>
Cc: Benno Lossin <[email protected]>
Cc: "Björn Roy Baron" <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Gary Guo <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Wedson Almeida Filho <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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lib: code tagging framework

Add basic infrastructure to support code tagging which stores tag common
information consisting of the module name, function, file name and line
number. Provide function

lib: code tagging framework

Add basic infrastructure to support code tagging which stores tag common
information consisting of the module name, function, file name and line
number. Provide functions to register a new code tag type and navigate
between code tags.

Link: https://lkml.kernel.org/r/[email protected]
Co-developed-by: Kent Overstreet <[email protected]>
Signed-off-by: Kent Overstreet <[email protected]>
Signed-off-by: Suren Baghdasaryan <[email protected]>
Tested-by: Kees Cook <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alex Gaynor <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Andreas Hindborg <[email protected]>
Cc: Benno Lossin <[email protected]>
Cc: "Björn Roy Baron" <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Gary Guo <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Pasha Tatashin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Wedson Almeida Filho <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...