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| author | Sergei Trofimovich <slyfox@gentoo.org> | 2021-04-30 08:53:48 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-30 21:20:35 +0300 |
| commit | 99e729bd40fb3272fa4b0140839d5e957b58588a (patch) | |
| tree | 95ce93c001ab5b06fbdd378eb79ec0a81fe392dc /arch/ia64/include | |
| parent | 9187592b96385e5060dfb2b182aa9ec93d5c0332 (diff) | |
| download | linux-99e729bd40fb3272fa4b0140839d5e957b58588a.tar.xz | |
ia64: module: fix symbolizer crash on fdescr
Noticed failure as a crash on ia64 when tried to symbolize all backtraces
collected by page_owner=on:
$ cat /sys/kernel/debug/page_owner
<oops>
CPU: 1 PID: 2074 Comm: cat Not tainted 5.12.0-rc4 #226
Hardware name: hp server rx3600, BIOS 04.03 04/08/2008
ip is at dereference_module_function_descriptor+0x41/0x100
Crash happens at dereference_module_function_descriptor() due to
use-after-free when dereferencing ".opd" section header.
All section headers are already freed after module is laoded successfully.
To keep symbolizer working the change stores ".opd" address and size after
module is relocated to a new place and before section headers are
discarded.
To make similar errors less obscure module_finalize() now zeroes out all
variables relevant to module loading only.
Link: https://lkml.kernel.org/r/20210403074803.3309096-1-slyfox@gentoo.org
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/ia64/include')
| -rw-r--r-- | arch/ia64/include/asm/module.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/ia64/include/asm/module.h b/arch/ia64/include/asm/module.h index 5a29652e6def..7271b9c5fc76 100644 --- a/arch/ia64/include/asm/module.h +++ b/arch/ia64/include/asm/module.h @@ -14,16 +14,20 @@ struct elf64_shdr; /* forward declration */ struct mod_arch_specific { + /* Used only at module load time. */ struct elf64_shdr *core_plt; /* core PLT section */ struct elf64_shdr *init_plt; /* init PLT section */ struct elf64_shdr *got; /* global offset table */ struct elf64_shdr *opd; /* official procedure descriptors */ struct elf64_shdr *unwind; /* unwind-table section */ unsigned long gp; /* global-pointer for module */ + unsigned int next_got_entry; /* index of next available got entry */ + /* Used at module run and cleanup time. */ void *core_unw_table; /* core unwind-table cookie returned by unwinder */ void *init_unw_table; /* init unwind-table cookie returned by unwinder */ - unsigned int next_got_entry; /* index of next available got entry */ + void *opd_addr; /* symbolize uses .opd to get to actual function */ + unsigned long opd_size; }; #define ARCH_SHF_SMALL SHF_IA_64_SHORT |