linux.git/arch/arm/kernel/vdso.c, branch v6.17

arm: vdso: Switch to generic storage implementation

2025-02-21T08:54:02+00:00

The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.

Co-developed-by: Nam Cao 
Signed-off-by: Nam Cao 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-11-13a4669dfc8c@linutronix.de

arm: vdso: Remove timekeeper includes

2024-10-15T15:50:29+00:00

Since the generic VDSO clock mode storage is used, this header file is
unused and can be removed.

This avoids including a non-VDSO header while building the VDSO,
which can lead to compilation errors.

Also drop the comment which is out of date and in the wrong place.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/20241010-vdso-generic-arch_update_vsyscall-v1-2-7fe5a3ea4382@linutronix.de

vdso/ARM: Make union vdso_data_store available for all architectures

2024-02-20T19:56:00+00:00

The vDSO data page "union vdso_data_store" is defined in an ARM specific
header file and also defined in several other places.

Move the definition from the ARM header file into the generic vdso datapage
header to make it also usable for others and to prevent code duplication.

Signed-off-by: Anna-Maria Behnsen 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Vincenzo Frascino 
Reviewed-by: Kees Cook 
Link: https://lore.kernel.org/r/20240219153939.75719-5-anna-maria@linutronix.de

ARM: 9300/1: Replace all non-returning strlcpy with strscpy

2023-06-19T08:35:49+00:00

strlcpy() reads the entire source buffer first.  This read may exceed
the destination size limit.  This is both inefficient and can lead to
linear read overflows if a source string is not NUL-terminated [1].  In
an effort to remove strlcpy() completely [2], replace strlcpy() here
with strscpy().  No return values were used, so direct replacement is
safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

[ardb: submitting to the patch tracker on behalf of Azeem]

Signed-off-by: Azeem Shaikh 
Reviewed-by: Linus Walleij 
Reviewed-by: Kees Cook 
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Russell King (Oracle)

mm: forbid splitting special mappings

2020-12-15T20:13:41+00:00

Don't allow splitting of vm_special_mapping's.  It affects vdso/vvar
areas.  Uprobes have only one page in xol_area so they aren't affected.

Those restrictions were enforced by checks in .mremap() callbacks.
Restrict resizing with generic .split() callback.

Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.com
Signed-off-by: Dmitry Safonov 
Cc: Alexander Viro 
Cc: Andy Lutomirski 
Cc: Brian Geffon 
Cc: Catalin Marinas 
Cc: Dan Carpenter 
Cc: Dan Williams 
Cc: Dave Jiang 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: "Kirill A. Shutemov" 
Cc: Mike Kravetz 
Cc: Minchan Kim 
Cc: Ralph Campbell 
Cc: Russell King 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vishal Verma 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ARM: 8987/1: VDSO: Fix incorrect clock_gettime64

2020-07-21T15:32:55+00:00

__vdso_*() should be removed and fallback used if CNTCVT is not
available by cntvct_functional(). __vdso_clock_gettime64 when added
previous commit is using the incorrect CNTCVT value in that state.
__vdso_clock_gettime64 is also added to remove it's symbol.

Cc: stable@vger.kernel.org
Fixes: 74d06efb9c2f ("ARM: 8932/1: Add clock_gettime64 entry point")
Signed-off-by: Jaedon Shin 
Tested-by: Robin Murphy 
Signed-off-by: Robin Murphy 
Signed-off-by: Russell King

mmap locking API: convert mmap_sem comments

2020-06-09T16:39:14+00:00

Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse 
Signed-off-by: Andrew Morton 
Reviewed-by: Vlastimil Babka 
Reviewed-by: Daniel Jordan 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Laurent Dufour 
Cc: Liam Howlett 
Cc: Matthew Wilcox 
Cc: Peter Zijlstra 
Cc: Ying Han 
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds

ARM: 8957/1: VDSO: Match ARMv8 timer in cntvct_functional()

2020-02-21T17:03:20+00:00

It is possible for a system with an ARMv8 timer to run a 32-bit kernel.
When this happens we will unconditionally have the vDSO code remove the
__vdso_gettimeofday and __vdso_clock_gettime symbols because
cntvct_functional() returns false since it does not match that
compatibility string.

Fixes: ecf99a439105 ("ARM: 8331/1: VDSO initialization, mapping, and synchronization")
Signed-off-by: Florian Fainelli 
Signed-off-by: Russell King

ARM: 8930/1: Add support for generic vDSO

2019-11-15T22:21:12+00:00

The arm vDSO library requires some adaptations to take advantage of
the newly introduced generic vDSO library.

Introduce the following changes:
 - Modification vdso.c to be compliant with the common vdso datapage
 - Use of lib/vdso for gettimeofday
 - Implementation of elf note

Signed-off-by: Vincenzo Frascino 
Signed-off-by: Russell King

ARM: 8896/1: VDSO: Don't leak kernel addresses

2019-08-23T10:39:32+00:00

Since commit ad67b74d2469d9b8 ("printk: hash addresses printed with
%p"), an obfuscated kernel pointer is printed at every boot if
debugging is enabled:

    vdso: 1 text pages at base (____ptrval____)

Remove the print completely, as it's useless without the address.

Based on commit 0f1bf7e39822476b ("arm64/vdso: don't leak kernel
addresses").

Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p")
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Russell King