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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-07-05 13:42:16 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-07-05 13:42:16 -0700 |
commit | eed0218e8cae9fcd186c30e9fcf5fe46a87e056e (patch) | |
tree | 799a1360b947a56d05a60433fdf60a96bf3b3348 /drivers/misc/lkdtm/heap.c | |
parent | 3f8b8e7dbd79086ad48fcff33de9399f3da66a69 (diff) | |
parent | 6f746d485fb9188dc67dce7de63d21f0c28a1f2e (diff) | |
download | lwn-eed0218e8cae9fcd186c30e9fcf5fe46a87e056e.tar.gz lwn-eed0218e8cae9fcd186c30e9fcf5fe46a87e056e.zip |
Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc driver updates from Greg KH:
"Here is the big set of char / misc and other driver subsystem updates
for 5.14-rc1. Included in here are:
- habanalabs driver updates
- fsl-mc driver updates
- comedi driver updates
- fpga driver updates
- extcon driver updates
- interconnect driver updates
- mei driver updates
- nvmem driver updates
- phy driver updates
- pnp driver updates
- soundwire driver updates
- lots of other tiny driver updates for char and misc drivers
This is looking more and more like the "various driver subsystems
mushed together" tree...
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
mcb: Use DEFINE_RES_MEM() helper macro and fix the end address
PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable
bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls
bus: mhi: Wait for M2 state during system resume
bus: mhi: core: Fix power down latency
intel_th: Wait until port is in reset before programming it
intel_th: msu: Make contiguous buffers uncached
intel_th: Remove an unused exit point from intel_th_remove()
stm class: Spelling fix
nitro_enclaves: Set Bus Master for the NE PCI device
misc: ibmasm: Modify matricies to matrices
misc: vmw_vmci: return the correct errno code
siox: Simplify error handling via dev_err_probe()
fpga: machxo2-spi: Address warning about unused variable
lkdtm/heap: Add init_on_alloc tests
selftests/lkdtm: Enable various testable CONFIGs
lkdtm: Add CONFIG hints in errors where possible
lkdtm: Enable DOUBLE_FAULT on all architectures
lkdtm/heap: Add vmalloc linear overflow test
lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE
...
Diffstat (limited to 'drivers/misc/lkdtm/heap.c')
-rw-r--r-- | drivers/misc/lkdtm/heap.c | 97 |
1 files changed, 92 insertions, 5 deletions
diff --git a/drivers/misc/lkdtm/heap.c b/drivers/misc/lkdtm/heap.c index 1323bc16f113..3d9aae5821a0 100644 --- a/drivers/misc/lkdtm/heap.c +++ b/drivers/misc/lkdtm/heap.c @@ -5,6 +5,7 @@ */ #include "lkdtm.h" #include <linux/slab.h> +#include <linux/vmalloc.h> #include <linux/sched.h> static struct kmem_cache *double_free_cache; @@ -12,17 +13,36 @@ static struct kmem_cache *a_cache; static struct kmem_cache *b_cache; /* + * If there aren't guard pages, it's likely that a consecutive allocation will + * let us overflow into the second allocation without overwriting something real. + */ +void lkdtm_VMALLOC_LINEAR_OVERFLOW(void) +{ + char *one, *two; + + one = vzalloc(PAGE_SIZE); + two = vzalloc(PAGE_SIZE); + + pr_info("Attempting vmalloc linear overflow ...\n"); + memset(one, 0xAA, PAGE_SIZE + 1); + + vfree(two); + vfree(one); +} + +/* * This tries to stay within the next largest power-of-2 kmalloc cache * to avoid actually overwriting anything important if it's not detected * correctly. */ -void lkdtm_OVERWRITE_ALLOCATION(void) +void lkdtm_SLAB_LINEAR_OVERFLOW(void) { size_t len = 1020; u32 *data = kmalloc(len, GFP_KERNEL); if (!data) return; + pr_info("Attempting slab linear overflow ...\n"); data[1024 / sizeof(u32)] = 0x12345678; kfree(data); } @@ -89,9 +109,10 @@ void lkdtm_READ_AFTER_FREE(void) if (saw != *val) { /* Good! Poisoning happened, so declare a win. */ pr_info("Memory correctly poisoned (%x)\n", saw); - BUG(); + } else { + pr_err("FAIL: Memory was not poisoned!\n"); + pr_expected_config_param(CONFIG_INIT_ON_FREE_DEFAULT_ON, "init_on_free"); } - pr_info("Memory was not poisoned\n"); kfree(val); } @@ -145,13 +166,79 @@ void lkdtm_READ_BUDDY_AFTER_FREE(void) if (saw != *val) { /* Good! Poisoning happened, so declare a win. */ pr_info("Memory correctly poisoned (%x)\n", saw); - BUG(); + } else { + pr_err("FAIL: Buddy page was not poisoned!\n"); + pr_expected_config_param(CONFIG_INIT_ON_FREE_DEFAULT_ON, "init_on_free"); + } + + kfree(val); +} + +void lkdtm_SLAB_INIT_ON_ALLOC(void) +{ + u8 *first; + u8 *val; + + first = kmalloc(512, GFP_KERNEL); + if (!first) { + pr_info("Unable to allocate 512 bytes the first time.\n"); + return; + } + + memset(first, 0xAB, 512); + kfree(first); + + val = kmalloc(512, GFP_KERNEL); + if (!val) { + pr_info("Unable to allocate 512 bytes the second time.\n"); + return; + } + if (val != first) { + pr_warn("Reallocation missed clobbered memory.\n"); } - pr_info("Buddy page was not poisoned\n"); + if (memchr(val, 0xAB, 512) == NULL) { + pr_info("Memory appears initialized (%x, no earlier values)\n", *val); + } else { + pr_err("FAIL: Slab was not initialized\n"); + pr_expected_config_param(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, "init_on_alloc"); + } kfree(val); } +void lkdtm_BUDDY_INIT_ON_ALLOC(void) +{ + u8 *first; + u8 *val; + + first = (u8 *)__get_free_page(GFP_KERNEL); + if (!first) { + pr_info("Unable to allocate first free page\n"); + return; + } + + memset(first, 0xAB, PAGE_SIZE); + free_page((unsigned long)first); + + val = (u8 *)__get_free_page(GFP_KERNEL); + if (!val) { + pr_info("Unable to allocate second free page\n"); + return; + } + + if (val != first) { + pr_warn("Reallocation missed clobbered memory.\n"); + } + + if (memchr(val, 0xAB, PAGE_SIZE) == NULL) { + pr_info("Memory appears initialized (%x, no earlier values)\n", *val); + } else { + pr_err("FAIL: Slab was not initialized\n"); + pr_expected_config_param(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, "init_on_alloc"); + } + free_page((unsigned long)val); +} + void lkdtm_SLAB_FREE_DOUBLE(void) { int *val; |