https://github.com/torvalds/linux
Revision 831b624df1b420c8f9281ed1307a8db23afb72df authored by Bin Yang on 12 September 2018, 03:36:34 UTC, committed by Kees Cook on 13 September 2018, 16:14:57 UTC
persistent_ram_vmap() returns the page start vaddr. persistent_ram_iomap() supports non-page-aligned mapping. persistent_ram_buffer_map() always adds offset-in-page to the vaddr returned from these two functions, which causes incorrect mapping of non-page-aligned persistent ram buffer. By default ftrace_size is 4096 and max_ftrace_cnt is nr_cpu_ids. Without this patch, the zone_sz in ramoops_init_przs() is 4096/nr_cpu_ids which might not be page aligned. If the offset-in-page > 2048, the vaddr will be in next page. If the next page is not mapped, it will cause kernel panic: [ 0.074231] BUG: unable to handle kernel paging request at ffffa19e0081b000 ... [ 0.075000] RIP: 0010:persistent_ram_new+0x1f8/0x39f ... [ 0.075000] Call Trace: [ 0.075000] ramoops_init_przs.part.10.constprop.15+0x105/0x260 [ 0.075000] ramoops_probe+0x232/0x3a0 [ 0.075000] platform_drv_probe+0x3e/0xa0 [ 0.075000] driver_probe_device+0x2cd/0x400 [ 0.075000] __driver_attach+0xe4/0x110 [ 0.075000] ? driver_probe_device+0x400/0x400 [ 0.075000] bus_for_each_dev+0x70/0xa0 [ 0.075000] driver_attach+0x1e/0x20 [ 0.075000] bus_add_driver+0x159/0x230 [ 0.075000] ? do_early_param+0x95/0x95 [ 0.075000] driver_register+0x70/0xc0 [ 0.075000] ? init_pstore_fs+0x4d/0x4d [ 0.075000] __platform_driver_register+0x36/0x40 [ 0.075000] ramoops_init+0x12f/0x131 [ 0.075000] do_one_initcall+0x4d/0x12c [ 0.075000] ? do_early_param+0x95/0x95 [ 0.075000] kernel_init_freeable+0x19b/0x222 [ 0.075000] ? rest_init+0xbb/0xbb [ 0.075000] kernel_init+0xe/0xfc [ 0.075000] ret_from_fork+0x3a/0x50 Signed-off-by: Bin Yang <bin.yang@intel.com> [kees: add comments describing the mapping differences, updated commit log] Fixes: 24c3d2f342ed ("staging: android: persistent_ram: Make it possible to use memory outside of bootmem") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
1 parent 5736184
Tip revision: 831b624df1b420c8f9281ed1307a8db23afb72df authored by Bin Yang on 12 September 2018, 03:36:34 UTC
pstore: Fix incorrect persistent ram buffer mapping
pstore: Fix incorrect persistent ram buffer mapping
Tip revision: 831b624
File | Mode | Size |
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LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | -rw-r--r-- | 12.8 KB |
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 31 bytes |
.gitattributes | -rw-r--r-- | 30 bytes |
.gitignore | -rw-r--r-- | 1.5 KB |
.mailmap | -rw-r--r-- | 9.7 KB |
COPYING | -rw-r--r-- | 423 bytes |
CREDITS | -rw-r--r-- | 96.4 KB |
Kbuild | -rw-r--r-- | 2.2 KB |
Kconfig | -rw-r--r-- | 563 bytes |
MAINTAINERS | -rw-r--r-- | 458.4 KB |
Makefile | -rw-r--r-- | 59.1 KB |
README | -rw-r--r-- | 800 bytes |
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