diff options
| -rw-r--r-- | arm64-__clear_user-handle-exceptions-on-strb.patch | 59 | ||||
| -rw-r--r-- | kernel.spec | 9 |
2 files changed, 68 insertions, 0 deletions
diff --git a/arm64-__clear_user-handle-exceptions-on-strb.patch b/arm64-__clear_user-handle-exceptions-on-strb.patch new file mode 100644 index 000000000..3fd69bc6c --- /dev/null +++ b/arm64-__clear_user-handle-exceptions-on-strb.patch @@ -0,0 +1,59 @@ +From 98e676789aa06582cb0d0f7758e77864b38c12a7 Mon Sep 17 00:00:00 2001 +From: Kyle McMartin <kyle@redhat.com> +Date: Wed, 12 Nov 2014 16:07:44 -0500 +Subject: [PATCH] arm64: __clear_user: handle exceptions on strb + +ARM64 currently doesn't fix up faults on the single-byte (strb) case of +__clear_user... which means that we can cause a nasty kernel panic as an +ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero. +i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.) + +This is a pretty obscure bug in the general case since we'll only +__do_kernel_fault (since there's no extable entry for pc) if the +mmap_sem is contended. However, with CONFIG_DEBUG_VM enabled, we'll +always fault. + +if (!down_read_trylock(&mm->mmap_sem)) { + if (!user_mode(regs) && !search_exception_tables(regs->pc)) + goto no_context; +retry: + down_read(&mm->mmap_sem); +} else { + /* + * The above down_read_trylock() might have succeeded in + * which + * case, we'll have missed the might_sleep() from + * down_read(). + */ + might_sleep(); +#ifdef CONFIG_DEBUG_VM + if (!user_mode(regs) && !search_exception_tables(regs->pc)) + goto no_context; +#endif +} + +Fix that by adding an extable entry for the strb instruction, since it +touches user memory, similar to the other stores in __clear_user. + +Signed-off-by: Kyle McMartin <kyle@redhat.com> +Cc: stable@vger.kernel.org +--- + arch/arm64/lib/clear_user.S | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/arch/arm64/lib/clear_user.S b/arch/arm64/lib/clear_user.S +index 6e0ed93d51fe..c17967fdf5f6 100644 +--- a/arch/arm64/lib/clear_user.S ++++ b/arch/arm64/lib/clear_user.S +@@ -46,7 +46,7 @@ USER(9f, strh wzr, [x0], #2 ) + sub x1, x1, #2 + 4: adds x1, x1, #1 + b.mi 5f +- strb wzr, [x0] ++USER(9f, strb wzr, [x0] ) + 5: mov x0, #0 + ret + ENDPROC(__clear_user) +-- +1.9.3 + diff --git a/kernel.spec b/kernel.spec index 4c2d43a61..c635d5807 100644 --- a/kernel.spec +++ b/kernel.spec @@ -622,6 +622,9 @@ Patch26066: ahci-disable-MSI-instead-of-NCQ-on-Samsung-pci-e-SSD.patch #CVE-2014-7841 rhbz 1163087 1163095 Patch26067: net-sctp-fix-NULL-pointer-dereference-in-af-from_add.patch +#CVE-2014-7843 rhbz 1163744 1163745 +Patch26069: arm64-__clear_user-handle-exceptions-on-strb.patch + # git clone ssh://git.fedorahosted.org/git/kernel-arm64.git, git diff master...devel Patch30000: kernel-arm64.patch @@ -1353,6 +1356,9 @@ ApplyPatch ahci-disable-MSI-instead-of-NCQ-on-Samsung-pci-e-SSD.patch #CVE-2014-7841 rhbz 1163087 1163095 ApplyPatch net-sctp-fix-NULL-pointer-dereference-in-af-from_add.patch +#CVE-2014-7843 rhbz 1163744 1163745 +ApplyPatch arm64-__clear_user-handle-exceptions-on-strb.patch + %if 0%{?aarch64patches} ApplyPatch kernel-arm64.patch %ifnarch aarch64 # this is stupid, but i want to notice before secondary koji does. @@ -2221,6 +2227,9 @@ fi # ||----w | # || || %changelog +* Thu Nov 13 2014 Josh Boyer <jwboyer@fedoraproject.org> +- CVE-2014-7843 aarch64: copying from /dev/zero causes local DoS (rhbz 1163744 1163745) + * Thu Nov 13 2014 Josh Boyer <jwboyer@fedoraproject.org> - 3.18.0-0.rc4.git1.1 - Linux v3.18-rc4-52-g04689e749b7e - Reenable debugging options. |