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author | Jaewon Kim <jaewon31.kim@samsung.com> | 2020-04-10 14:32:48 -0700 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-01 20:40:11 +0200 |
commit | c21895bbe1d5038d39f082ae206214360ddc3ca3 (patch) | |
tree | 6ce2b977317e711ea260694103f231c92f739c4c /mm | |
parent | ea44cd77fd9a9c7317ada529b77644f0788c4092 (diff) | |
download | linux-rt-c21895bbe1d5038d39f082ae206214360ddc3ca3.tar.gz |
mm/mmap.c: initialize align_offset explicitly for vm_unmapped_area
[ Upstream commit 09ef5283fd96ac424ef0e569626f359bf9ab86c9 ]
On passing requirement to vm_unmapped_area, arch_get_unmapped_area and
arch_get_unmapped_area_topdown did not set align_offset. Internally on
both unmapped_area and unmapped_area_topdown, if info->align_mask is 0,
then info->align_offset was meaningless.
But commit df529cabb7a2 ("mm: mmap: add trace point of
vm_unmapped_area") always prints info->align_offset even though it is
uninitialized.
Fix this uninitialized value issue by setting it to 0 explicitly.
Before:
vm_unmapped_area: addr=0x755b155000 err=0 total_vm=0x15aaf0 flags=0x1 len=0x109000 lo=0x8000 hi=0x75eed48000 mask=0x0 ofs=0x4022
After:
vm_unmapped_area: addr=0x74a4ca1000 err=0 total_vm=0x168ab1 flags=0x1 len=0x9000 lo=0x8000 hi=0x753d94b000 mask=0x0 ofs=0x0
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200409094035.19457-1-jaewon31.kim@samsung.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/mmap.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 7109f886e739..7c8815636c48 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2028,6 +2028,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, info.low_limit = mm->mmap_base; info.high_limit = TASK_SIZE; info.align_mask = 0; + info.align_offset = 0; return vm_unmapped_area(&info); } #endif @@ -2069,6 +2070,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, info.low_limit = max(PAGE_SIZE, mmap_min_addr); info.high_limit = mm->mmap_base; info.align_mask = 0; + info.align_offset = 0; addr = vm_unmapped_area(&info); /* |