[PW_SID:1148636] kexec: fix probe error codes and error propagation - #2501
[PW_SID:1148636] kexec: fix probe error codes and error propagation#2501linux-riscv-bot wants to merge 5 commits into
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…_RWX When CONFIG_STRICT_MODULE_RWX is not set, execmem cannot create temporary writable mappings for read-only executable pages. In this case, the execmem ranges must already have writable permissions. Currently EXECMEM_KPROBES unconditionally uses PAGE_KERNEL_READ_EXEC, which causes kprobe instruction slot writes to trigger page faults on systems where CONFIG_STRICT_MODULE_RWX is not enabled. Fix this by using PAGE_KERNEL_EXEC when CONFIG_STRICT_MODULE_RWX is not available. Signed-off-by: Xiaofeng Yuan <xiaofengmian@163.com> Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Nam Cao <namcao@linutronix.de> Link: https://patch.msgid.link/20260814082742.148403-2-xiaofengmian@163.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
patch_map() always creates a temporary writable mapping via fixmap for kernel text addresses, even when CONFIG_STRICT_KERNEL_RWX is disabled and the kernel text is already mapped with _PAGE_WRITE. This is unnecessary overhead at best, and on minimal configurations it can cause page faults. Skip the fixmap path for kernel text when CONFIG_STRICT_KERNEL_RWX is not enabled, since the text pages are already writable in that case. The module text path is already gated on CONFIG_STRICT_MODULE_RWX and is kept unchanged. Reported-by: Klara Modin <klara@kasm.eu> Closes: https://lore.kernel.org/all/ant_8TaBbov_GS4i@soda.int.kasm.eu/ Reported-by: Lad Prabhakar <prabhakar.csengg@gmail.com> Closes: https://lore.kernel.org/all/CA+V-a8tQK8rih9SGGTyqrEBGpNkx4H0eX2YccCRrgkVAPr+EBg@mail.gmail.com/ Tested-by: Klara Modin <klarasmodin@gmail.com> Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Link: https://patch.msgid.link/20260814082742.148403-3-xiaofengmian@163.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
Several kexec_file_load() image probe functions return -EINVAL when they do not recognize the image format. A probe function that rejects an image should return -ENOEXEC to indicate that the image is not a recognized executable format. -EINVAL implies a problem with the syscall parameters, not with image recognition. kexec_image_probe_default() iterates through registered loaders and returns the last probe's error code to the caller. That error propagates as the kexec_file_load() return value to userspace. Returning -EINVAL from a probe when no loader matches is semantically incorrect and misleads userspace about the nature of the failure. Return -ENOEXEC from all probe functions and their helpers when the image format is not recognized. Signed-off-by: Mukesh Pilaniya <mpilaniy@redhat.com> Reviewed-by: Philipp Rudo <prudo@redhat.com> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>
kexec_image_probe_default() overwrites ret with each loader's probe return value and returns whatever the last loader returned when no probe matches. The error code reaching userspace depends on whichever loader happens to be last in kexec_file_loaders[]. Only continue to the next loader when a probe returns -ENOEXEC. Propagate any other error such as -ENOMEM immediately. Return -ENOEXEC only when all loaders have been tried and none matched. Suggested-by: Pratyush Yadav <pratyush@kernel.org> Signed-off-by: Mukesh Pilaniya <mpilaniy@redhat.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 1: "[v2,1/2] kexec: return -ENOEXEC from image probe functions on mismatch" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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Patch 2: "[v2,2/2] kexec: fix error propagation in kexec_image_probe_default()" |
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PR for series 1148636 applied to workflow__riscv__fixes
Name: kexec: fix probe error codes and error propagation
URL: https://patchwork.kernel.org/project/linux-riscv/list/?series=1148636
Version: 2