diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2024-08-20 19:23:46 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2024-08-30 21:29:52 +1000 |
| commit | 65a82e117ffeeab0baf6f871a1cab11a28ace183 (patch) | |
| tree | c3709282cefa7323a87df4dbc7b803add50e216b | |
| parent | f9f2bff64c2f0dbee57be3d8c2741357ad3d05e6 (diff) | |
powerpc/8xx: Fix kernel vs user address comparison
Since commit 9132a2e82adc ("powerpc/8xx: Define a MODULE area below
kernel text"), module exec space is below PAGE_OFFSET so not only
space above PAGE_OFFSET, but space above TASK_SIZE need to be seen
as kernel space.
Until now the problem went undetected because by default TASK_SIZE
is 0x8000000 which means address space is determined by just
checking upper address bit. But when TASK_SIZE is over 0x80000000,
PAGE_OFFSET is used for comparison, leading to thinking module
addresses are part of user space.
Fix it by using TASK_SIZE instead of PAGE_OFFSET for address
comparison.
Fixes: 9132a2e82adc ("powerpc/8xx: Define a MODULE area below kernel text")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/3f574c9845ff0a023b46cb4f38d2c45aecd769bd.1724173828.git.christophe.leroy@csgroup.eu
| -rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index ac74321b1192..c955a8196d55 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -41,12 +41,12 @@ #include "head_32.h" .macro compare_to_kernel_boundary scratch, addr -#if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000 +#if CONFIG_TASK_SIZE <= 0x80000000 && MODULES_VADDR >= 0x80000000 /* By simply checking Address >= 0x80000000, we know if its a kernel address */ not. \scratch, \addr #else rlwinm \scratch, \addr, 16, 0xfff8 - cmpli cr0, \scratch, PAGE_OFFSET@h + cmpli cr0, \scratch, TASK_SIZE@h #endif .endm @@ -404,7 +404,7 @@ FixupDAR:/* Entry point for dcbx workaround. */ mfspr r10, SPRN_SRR0 mtspr SPRN_MD_EPN, r10 rlwinm r11, r10, 16, 0xfff8 - cmpli cr1, r11, PAGE_OFFSET@h + cmpli cr1, r11, TASK_SIZE@h mfspr r11, SPRN_M_TWB /* Get level 1 table */ blt+ cr1, 3f |