From 0f70fe605fad0f3215818ba79fc12617c0ec7f90 Mon Sep 17 00:00:00 2001 From: Horacio Mijail Anton Quiles Date: Fri, 17 Jul 2015 16:24:04 -0700 Subject: hexdump: fix for non-aligned buffers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A hexdump with a buf not aligned to the groupsize causes non-naturally-aligned memory accesses. This was causing a kernel panic on the processor BlackFin BF527, when such an unaligned buffer was fed by the function ubifs_scanned_corruption in fs/ubifs/scan.c . To fix this, change accesses to the contents of the buffer so they go through get_unaligned(). This change should be harmless to unaligned- access-capable architectures, and any performance hit should be anyway dwarfed by the snprintf() processing time. Signed-off-by: Horacio Mijail Antón Quiles Cc: Andy Shevchenko Cc: David Howells Cc: Vivek Goyal Cc: Joe Perches Acked-by: Geert Uytterhoeven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/hexdump.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/lib/hexdump.c b/lib/hexdump.c index 7ea09699855d..8d74c20d8595 100644 --- a/lib/hexdump.c +++ b/lib/hexdump.c @@ -11,6 +11,7 @@ #include #include #include +#include const char hex_asc[] = "0123456789abcdef"; EXPORT_SYMBOL(hex_asc); @@ -139,7 +140,7 @@ int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize, for (j = 0; j < ngroups; j++) { ret = snprintf(linebuf + lx, linebuflen - lx, "%s%16.16llx", j ? " " : "", - (unsigned long long)*(ptr8 + j)); + get_unaligned(ptr8 + j)); if (ret >= linebuflen - lx) goto overflow1; lx += ret; @@ -150,7 +151,7 @@ int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize, for (j = 0; j < ngroups; j++) { ret = snprintf(linebuf + lx, linebuflen - lx, "%s%8.8x", j ? " " : "", - *(ptr4 + j)); + get_unaligned(ptr4 + j)); if (ret >= linebuflen - lx) goto overflow1; lx += ret; @@ -161,7 +162,7 @@ int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize, for (j = 0; j < ngroups; j++) { ret = snprintf(linebuf + lx, linebuflen - lx, "%s%4.4x", j ? " " : "", - *(ptr2 + j)); + get_unaligned(ptr2 + j)); if (ret >= linebuflen - lx) goto overflow1; lx += ret; -- cgit v1.2.3