swh:1:snp:38ae39f9fd01a4b0ef06fab5668b65bf4c2aca03
Revision 68d54ceeec0e5fee4fb8048e6a04c193f32525ca authored by Catalin Marinas on 10 February 2021, 18:03:16 UTC, committed by Catalin Marinas on 12 February 2021, 16:08:31 UTC
The ptrace(PTRACE_PEEKMTETAGS) implementation checks whether the user page has valid tags (mapped with PROT_MTE) by testing the PG_mte_tagged page flag. If this bit is cleared, ptrace(PTRACE_PEEKMTETAGS) returns -EIO. A newly created (PROT_MTE) mapping points to the zero page which had its tags zeroed during cpu_enable_mte(). If there were no prior writes to this mapping, ptrace(PTRACE_PEEKMTETAGS) fails with -EIO since the zero page does not have the PG_mte_tagged flag set. Set PG_mte_tagged on the zero page when its tags are cleared during boot. In addition, to avoid ptrace(PTRACE_PEEKMTETAGS) succeeding on !PROT_MTE mappings pointing to the zero page, change the __access_remote_tags() check to (vm_flags & VM_MTE) instead of PG_mte_tagged. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Fixes: 34bfeea4a9e9 ("arm64: mte: Clear the tags when a page is mapped in user-space with PROT_MTE") Cc: <stable@vger.kernel.org> # 5.10.x Cc: Will Deacon <will@kernel.org> Reported-by: Luis Machado <luis.machado@linaro.org> Tested-by: Luis Machado <luis.machado@linaro.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20210210180316.23654-1-catalin.marinas@arm.com
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Tip revision: 0cdd776ec92c0fec768c7079331804d3e52d4b27 authored by Linus Torvalds on 15 May 2022, 15:08:51 UTC
Merge tag 'driver-core-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Merge tag 'driver-core-5.18-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Tip revision: 0cdd776
File | Mode | Size |
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Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | -rw-r--r-- | 16.3 KB |
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 71 bytes |
.gitattributes | -rw-r--r-- | 62 bytes |
.gitignore | -rw-r--r-- | 1.8 KB |
.mailmap | -rw-r--r-- | 17.9 KB |
COPYING | -rw-r--r-- | 496 bytes |
CREDITS | -rw-r--r-- | 97.9 KB |
Kbuild | -rw-r--r-- | 1.3 KB |
Kconfig | -rw-r--r-- | 555 bytes |
MAINTAINERS | -rw-r--r-- | 572.1 KB |
Makefile | -rw-r--r-- | 62.9 KB |
README | -rw-r--r-- | 727 bytes |
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