| Message ID | 20211215021348.8766-1-kernelfans@gmail.com |
|---|---|
| State | Accepted |
| Commit | b398123bff3bcbc1facb0f29bf6e7b9f1bc55931 |
| Headers | show |
| Series | [PATCHv3] efi: apply memblock cap after memblock_add() | expand |
On Wed, 15 Dec 2021 10:13:48 +0800, Pingfan Liu wrote: > On arm64, during kdump kernel saves vmcore, it runs into the following bug: > ... > [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)! > [ 15.159707] ------------[ cut here ]------------ > [ 15.164311] kernel BUG at mm/usercopy.c:99! > [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP > [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop > [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1 > [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021 > [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > [ 15.228073] pc : usercopy_abort+0x9c/0xa0 > [ 15.232074] lr : usercopy_abort+0x9c/0xa0 > [ 15.236070] sp : ffff8000121abba0 > [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000 > [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000 > [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001 > [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff > [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420 > [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074 > [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c > [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000 > [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000 > [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b > [ 15.310593] Call trace: > [ 15.313027] usercopy_abort+0x9c/0xa0 > [ 15.316677] __check_heap_object+0xd4/0xf0 > [ 15.320762] __check_object_size.part.0+0x160/0x1e0 > [ 15.325628] __check_object_size+0x2c/0x40 > [ 15.329711] copy_oldmem_page+0x7c/0x140 > [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0 > [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350 > [ 15.342920] read_vmcore+0x28/0x34 > [ 15.346309] proc_reg_read+0xb4/0xf0 > [ 15.349871] vfs_read+0xb8/0x1f0 > [ 15.353088] ksys_read+0x74/0x100 > [ 15.356390] __arm64_sys_read+0x28/0x34 > ... > > This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom > linux,usable-memory-range handling"), which moves > memblock_cap_memory_range() to fdt, but it breaches the rules that > memblock_cap_memory_range() should come after memblock_add() etc as said > in commit e888fa7bb882 ("memblock: Check memory add/cap ordering"). > > As a consequence, the virtual address set up by copy_oldmem_page() does > not bail out from the test of virt_addr_valid() in check_heap_object(), > and finally hits the BUG_ON(). > > Since memblock allocator has no idea about when the memblock is fully > populated, while efi_init() is aware, so tackling this issue by calling the > interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt. > > Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Zhen Lei <thunder.leizhen@huawei.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Mike Rapoport <rppt@kernel.org> > Cc: Geert Uytterhoeven <geert+renesas@glider.be> > Cc: Frank Rowand <frowand.list@gmail.com> > Cc: Ard Biesheuvel <ardb@kernel.org> > Cc: Nick Terrell <terrelln@fb.com> > Cc: linux-arm-kernel@lists.infradead.org > To: devicetree@vger.kernel.org > To: linux-efi@vger.kernel.org > --- > v2 -> v3: > use static inline stub to avoid #ifdef according to Rob's suggestion > > drivers/firmware/efi/efi-init.c | 5 +++++ > drivers/of/fdt.c | 2 +- > include/linux/of_fdt.h | 2 ++ > 3 files changed, 8 insertions(+), 1 deletion(-) > Applied, thanks!
On 2021/12/15 10:13, Pingfan Liu wrote: > > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c > index 18a2df431bfd..aa07ef5cab5f 100644 > --- a/drivers/of/fdt.c > +++ b/drivers/of/fdt.c > @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; > * location from flat tree > * @node: reference to node containing usable memory range location ('chosen') > */ > -static void __init early_init_dt_check_for_usable_mem_range(void) > +void __init early_init_dt_check_for_usable_mem_range(void) Why do I see a parameter 'node'? master: drivers/of/fdt.c:976:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) next: drivers/of/fdt.c:980:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) > { > const __be32 *prop; > int len; > diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h > index cf48983d3c86..ad09beb6d13c 100644 > --- a/include/linux/of_fdt.h > +++ b/include/linux/of_fdt.h > @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname, > int depth, void *data); > extern int early_init_dt_scan_memory(unsigned long node, const char *uname, > int depth, void *data); > +extern void early_init_dt_check_for_usable_mem_range(void); > extern int early_init_dt_scan_chosen_stdout(void); > extern void early_init_fdt_scan_reserved_mem(void); > extern void early_init_fdt_reserve_self(void); > @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void); > extern void early_init_devtree(void *); > extern void early_get_first_memblock_info(void *, phys_addr_t *); > #else /* CONFIG_OF_EARLY_FLATTREE */ > +static inline void early_init_dt_check_for_usable_mem_range(void) {} > static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; } > static inline void early_init_fdt_scan_reserved_mem(void) {} > static inline void early_init_fdt_reserve_self(void) {} >
On 2021/12/22 16:00, Leizhen (ThunderTown) wrote: > > > On 2021/12/15 10:13, Pingfan Liu wrote: >> >> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c >> index 18a2df431bfd..aa07ef5cab5f 100644 >> --- a/drivers/of/fdt.c >> +++ b/drivers/of/fdt.c >> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; >> * location from flat tree >> * @node: reference to node containing usable memory range location ('chosen') >> */ >> -static void __init early_init_dt_check_for_usable_mem_range(void) >> +void __init early_init_dt_check_for_usable_mem_range(void) > > Why do I see a parameter 'node'? Sorry, I just saw that the patch 1/2 in v2 was also applied. > > master: > drivers/of/fdt.c:976:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) > > next: > drivers/of/fdt.c:980:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) > >> { >> const __be32 *prop; >> int len; >> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h >> index cf48983d3c86..ad09beb6d13c 100644 >> --- a/include/linux/of_fdt.h >> +++ b/include/linux/of_fdt.h >> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname, >> int depth, void *data); >> extern int early_init_dt_scan_memory(unsigned long node, const char *uname, >> int depth, void *data); >> +extern void early_init_dt_check_for_usable_mem_range(void); >> extern int early_init_dt_scan_chosen_stdout(void); >> extern void early_init_fdt_scan_reserved_mem(void); >> extern void early_init_fdt_reserve_self(void); >> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void); >> extern void early_init_devtree(void *); >> extern void early_get_first_memblock_info(void *, phys_addr_t *); >> #else /* CONFIG_OF_EARLY_FLATTREE */ >> +static inline void early_init_dt_check_for_usable_mem_range(void) {} >> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; } >> static inline void early_init_fdt_scan_reserved_mem(void) {} >> static inline void early_init_fdt_reserve_self(void) {} >>
diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index b19ce1a83f91..b2c829e95bd1 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -235,6 +235,11 @@ void __init efi_init(void) } reserve_regions(); + /* + * For memblock manipulation, the cap should come after the memblock_add(). + * And now, memblock is fully populated, it is time to do capping. + */ + early_init_dt_check_for_usable_mem_range(); efi_esrt_init(); efi_mokvar_table_init(); diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 18a2df431bfd..aa07ef5cab5f 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; * location from flat tree * @node: reference to node containing usable memory range location ('chosen') */ -static void __init early_init_dt_check_for_usable_mem_range(void) +void __init early_init_dt_check_for_usable_mem_range(void) { const __be32 *prop; int len; diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h index cf48983d3c86..ad09beb6d13c 100644 --- a/include/linux/of_fdt.h +++ b/include/linux/of_fdt.h @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname, int depth, void *data); extern int early_init_dt_scan_memory(unsigned long node, const char *uname, int depth, void *data); +extern void early_init_dt_check_for_usable_mem_range(void); extern int early_init_dt_scan_chosen_stdout(void); extern void early_init_fdt_scan_reserved_mem(void); extern void early_init_fdt_reserve_self(void); @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void); extern void early_init_devtree(void *); extern void early_get_first_memblock_info(void *, phys_addr_t *); #else /* CONFIG_OF_EARLY_FLATTREE */ +static inline void early_init_dt_check_for_usable_mem_range(void) {} static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; } static inline void early_init_fdt_scan_reserved_mem(void) {} static inline void early_init_fdt_reserve_self(void) {}
On arm64, during kdump kernel saves vmcore, it runs into the following bug: ... [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)! [ 15.159707] ------------[ cut here ]------------ [ 15.164311] kernel BUG at mm/usercopy.c:99! [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1 [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021 [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 15.228073] pc : usercopy_abort+0x9c/0xa0 [ 15.232074] lr : usercopy_abort+0x9c/0xa0 [ 15.236070] sp : ffff8000121abba0 [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000 [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000 [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001 [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420 [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074 [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000 [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000 [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b [ 15.310593] Call trace: [ 15.313027] usercopy_abort+0x9c/0xa0 [ 15.316677] __check_heap_object+0xd4/0xf0 [ 15.320762] __check_object_size.part.0+0x160/0x1e0 [ 15.325628] __check_object_size+0x2c/0x40 [ 15.329711] copy_oldmem_page+0x7c/0x140 [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0 [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350 [ 15.342920] read_vmcore+0x28/0x34 [ 15.346309] proc_reg_read+0xb4/0xf0 [ 15.349871] vfs_read+0xb8/0x1f0 [ 15.353088] ksys_read+0x74/0x100 [ 15.356390] __arm64_sys_read+0x28/0x34 ... This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling"), which moves memblock_cap_memory_range() to fdt, but it breaches the rules that memblock_cap_memory_range() should come after memblock_add() etc as said in commit e888fa7bb882 ("memblock: Check memory add/cap ordering"). As a consequence, the virtual address set up by copy_oldmem_page() does not bail out from the test of virt_addr_valid() in check_heap_object(), and finally hits the BUG_ON(). Since memblock allocator has no idea about when the memblock is fully populated, while efi_init() is aware, so tackling this issue by calling the interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt. Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling") Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Zhen Lei <thunder.leizhen@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Cc: linux-arm-kernel@lists.infradead.org To: devicetree@vger.kernel.org To: linux-efi@vger.kernel.org --- v2 -> v3: use static inline stub to avoid #ifdef according to Rob's suggestion drivers/firmware/efi/efi-init.c | 5 +++++ drivers/of/fdt.c | 2 +- include/linux/of_fdt.h | 2 ++ 3 files changed, 8 insertions(+), 1 deletion(-)